Description:FIELD OF THE INVENTION:
The present invention discloses a system and a method thereof for visible light communication for healthcare facilities. More particularly, the present invention discloses a system and a method thereof for effective data communication for healthcare facilities such as intensive care units (ICUs) and NICUs based on visible light communication that provides an ecofriendly solution to the challenges of spectrum crunch and health concerns associated with traditional radio communication technologies.

BACKGROUND OF THE INVENTION:
Wireless technology is a vital component of medical body area networks (MBANs), enabling flexibility and convenience for both healthcare providers and patients. However, within certain hospital zones, the use of mobile phones and RF devices is often prohibited. This restriction is enforced because these devices can create interference with sensitive medical equipment, potentially jeopardizing patient safety. Moreover, the risks are particularly acute for specific vulnerable populations, such as patients with implants and newborn infants. Newborns, in particular, are extremely susceptible to even minimal exposure to radiofrequency radiation, which can have serious implications for their health and development. As a result, it becomes imperative for healthcare facilities to implement alternative communication solutions that are not only effective but also eco-friendly, ensuring a safe and supportive environment for all patients.

In the context of NICU, the importance of an effective health monitoring system cannot be overstated. Premature or ill babies admitted to the NICU require continuous monitoring for their survival. In certain cases, the doctors must monitor the vital signs of babies from outside the NICU and provide recommendations to the healthcare personnel attending to them. This emphasizes the need for safer and more reliable communication technology in environments like hospitals, where RF restrictions are imposed.

A number of literatures have been published including patent and non-patent documents in said domain.
A non-patent literature by Yee Yong Tan, Sang-Joong Jung, and Wan-Young Chung, titled as “Real Time Biomedical Signal Transmission of Mixed ECG Signal and Patient Information using Visible Light Communication”, published in 2013, discloses that utilization of radiofrequency (RF) communication technology in healthcare applications, especially in the transmission of health-related data such as biomedical signal, the patient information is often perturbed by electromagnetic interference (EMI). This will not only significantly reduce the accuracy and reliability of the data transmitted but could also compromise the safety of the patients due to radio frequency (RF) radiation. Furthermore, conventional RF communication faces constraints in terms of spectrum availability for high data rate transmission.

VLC due to its wider bandwidth is being explored as a substitute for RF in various fields such as medical applications, underwater communication, indoor positioning and vehicle-to-vehicle communication. VLC offers certain distinct advantages over RF systems, including an uncongested frequency spectrum and a wider bandwidth. This enables higher transmission rates and faster speeds for short-range communication along with illumination making it highly suitable for healthcare settings. A key challenge in using VLC for medical applications is ensuring signal integrity despite noise interference. Biomedical signals, such as those from vital sign monitors, typically have low amplitudes, making them susceptible to external noise, ambient light variations, and signal attenuation. Traditional VLC systems often struggle to maintain high data integrity and low error rates under such conditions, which can lead to data loss or misinterpretation—posing risks in critical healthcare settings.

Another reference is made to a patent document EP-17807749-A, titled as “A receiver, method, terminal device, light transmissive structure and system for visible light communication”. This document relates to a receiver, a method and a terminal device comprising a receiver for receiving and processing visible light signals in a visible light communication system. It comprises of a photo detector array for receiving and converting a visible light signal into an electrical signal, a processor, a visible light transmissive structure, one lighting device etc. This document provides a general-purpose visible light communication (VLC) system, not tailored for the highly specialized needs of ICUs or NICUs, the environment of which carries unique challenges and requirements, such as minimizing RF interference to protect sensitive medical equipment etc. The document does not focus on healthcare or specific patient monitoring, but rather on the broad application of VLC technology. The document emphasizes the overall advantages for VLC systems but lacks detailed technical performance metrics.

A non-patent literature by Harald Haas, Liang Yin, and Cheng Chen et al., titled ‘‘Introduction to Indoor Networking Concepts and challenges in LiFi,’’ published in 2020, presents the indoor networking principles and challenges in visible light communication. This article discusses fundamental networking technologies like hybrid LiFi/Wi-Fi networking topologies and interference avoidance. The paper demonstrates the benefits of VLC technology, for sixth generation (6G) cellular connections and touches upon VLC, it is an alternative approach for load balancing in indoor communication. However, the article fails to describe the characteristics of VLC sufficiently. The systems presented in the article are highly likely to compromise on data integrity with high rates of error in data transmission.

Another non patent document by Qunzhen F and Hao Wu, titled, ‘‘Study on LED visible light communication channel model based on Poisson stochastic network theory’’, published in 2020, discloses the VLC channel model based on Poisson stochastic network theory and its application to produce a VLC channel model. Additionally, this publication describes their system’s indoor LED light layout approach establishing simulation experiments with VLC theories. However, the paper does not simulate the noise distribution layout with distance. These prior art documents do not address the challenges faced by VLC in noise removal from the transmitted signal.

Another non patent document by Klaas M, Wesley Da Silva, Van der Z, and Marianne Pontara M, titled, ‘‘A Manchester-OOK visible light communication system for patient monitoring in intensive care units,’’ published in 2021, presents a patient monitoring system using Manchester-OOK visible light communication. A VLC system is presented in this paper to include characterizations and experimental performance. This project focuses on the transmission of the Manchester-based OOK signal, in a proof-of concept mechanism that makes use of the Eye Opening Penalty (EOP) metric. Here, factors such as line-of-sight link distance, modulation frequency, LED bias current, and signal pattern were evaluated. However, the paper lacked in addressing certain major issues associated with VLC communications such as problem in the illuminance distribution according to distance etc. The paper in the literature does not present the selection of positions of the VLC transmitter and receiver units in ICUs and it lacks the interference analysis from other ICU bed units as well.

Another non – patent literature by Mahesh Kumar and Navin Kumar An analysis of the performance of multi-user optical MIMO (Multiple Input-Multiple Output) for VLC research paper was presented by as part of their study, they analyzed both the repetition coding (RC) and spatial modulation (SM) techniques to determine what bit error rate (BER) was induced. Based on the simulation results, it appears that spatial modulation offers better performance, especially at the lower end of the signal-to-noise ratio (SNR). However, the document does not focus on the distribution of ambient noise inside the room when studying this analysis.

Another reference is made to non-patented document by Yee-Yong Tan and Wan-Young Chung titled as “Mobile health–monitoring system through visible light communication”. This paper presents a mobile–health monitoring system, where healthcare information such as biomedical signals and patient information are transmitted via the LED lighting. The paper in the literature fails to present a two-way communication architecture and it lacks the interference analysis as well. Therefore, it does not provide a solution to the requirements of speedy transmission and reliable communication of health data within a constrained environment such as ICU or NICU.

Based on the literature review conducted, it appears that no previous studies have proposed a VLC-based system specifically designed for ICU or NICU units to deal with the detrimental effects of RF radiation while also incorporating smart healthcare capabilities. These studies do not facilitate any effective implementation of VLC addressing the unique challenges and requirements of this environment. in such highly sensitive environments like ICUs and NICUs.

Therefore, there is a sizable drawback in the state of the art implying the need to develop a robust VLC system and a method with smart capabilities for effective, accurate and reliable two- way healthcare communication in ICUs or NICUs while being cost effective and ecofriendly.

OBJECT OF THE INVENTION:
To overcome the shortcomings in the existing state of the art the main object of the present invention is to provide a system for visible light communication for healthcare facilities.

Yet another object of the present invention is to provide a system for healthcare communication that replaces the traditional wired communication systems with a wireless VLC-based system in sensitive healthcare zones such as Intensive care units (ICUs) and NICUs.

Yet another object of the present invention is to provide effective healthcare communication in healthcare facilities that overcomes the challenges of spectrum crunch and health concerns associated with traditional radio communication technologies.

Yet another object of the present invention is to provide a system for visible light communication for healthcare facilities to ensure reliable healthcare data transmission with minimal interference and effective noise removal.

Yet another object of the present invention is to provide a system for visible light communication for healthcare facilities which is effective in overcoming the challenges of state-of-the-art VLC systems like distribution of ambient noise, blockage in VLC channels, the distribution of illuminance and noise etc.

Yet another object of the present invention is to provide a system for effective healthcare communication in healthcare facilities that have dual functions of data transmission and durable lighting as well.

Yet another object of the present invention is to provide an efficient healthcare communication system that facilitates continuous monitoring of vital health parameters of patients in healthcare facilities such as ICUs or NICUs remotely by healthcare professionals thus reducing the need for their constant physical presence in these facilities.

Yet another object of the present invention is to provide a system for visible light communication for healthcare facilities that are energy efficient, eco-friendly and sustainable.

Yet another object of the present invention is to provide a system for visible light communication for healthcare facilities that are cost effective and versatile.

Yet another object of the present invention is to provide an effective method for visible light communication for healthcare facilities that is easy to implement.

SUMMARY OF THE INVENTION:
The present invention discloses a system and a method thereof for visible light communication for healthcare facilities. More particularly, the present invention discloses a system and a method thereof for effective data communication for healthcare facilities such as intensive care units (ICUs) and NICUs based on visible light communication that provides an ecofriendly solution to the challenges of spectrum crunch and health concerns associated with traditional radio communication technologies.

The present invention provides a VLC system that is specially designed for reliable data transmission of vital signs of patients in the healthcare facilities such as but not limited to Intensive Care Units (ICUs), Neonatal Intensive Care Units (NICUs) to the healthcare specialists’ portable communication devices. In the context of a NICU premature or ill babies admitted to the NICU require continuous monitoring for their survival. By utilizing this wireless communication technology of the invention, healthcare specialists such as doctors can remotely access and analyze the vital data of the patients or neonatal babies, enabling them to make informed decisions and provide guidance to the on-site healthcare team. This remote monitoring capability allows for efficient healthcare management and timely interventions when required. The system utilizes VLC as an alternative to RF technology and is particularly advantageous in enabling simultaneous illumination and communication capabilities. Therefore, it is apparent that the VLC-based system of the present invention efficiently deals with the detrimental effects of RF radiation while also incorporating smart healthcare capabilities for health care facilities, especially for RF-restricted healthcare facilities such as ICU or NICU units.
The invention describes the different modules involved in the transmitter and receiver functions of the system for establishing a two-way communication using visible light in a healthcare setup. It also presents various optimal VLC architectures, designed by considering factors such as cost-effectiveness and the number of patient units in the ICUs to be monitored. These architectures of the system of the invention have been developed with flexibility in mind, ensuring that these can be adapted to the evolving mobility requirements of units in ICUs or incubators in the NICUs thereby reducing the need for cumbersome and restrictive hard-wired communication cables in such sensitive environment. To ensure reliable data transmission, the interference analysis of the system was performed and presented, considering potential interferences induced by ambient light during transmission.
The system comprises of various modules such as but not limited to patient monitoring module, data acquisition module, processing module, transmitter modules, receiver modules, healthcare specialist modules, communication modules etc. that facilitate a two-way visible light communication in a healthcare facility providing comprehensive real-time monitoring of vital parameters. The health parameters of the patient being monitored such as but not limited to heart rate, temperature, oxygen saturation, blood pressure, other essential metrics are acquired by acquisition module of the system. The processing module performs the main processing function, efficiently converting the measured parameters of the patients acquired from the acquisition module into binary data. These binary values are then transmitted to the transmitter modules in an uplink communication channel of the VLC system , where a high-power transmitter connected to the patient unit/incubator emits visible light signals. The receiver module captures the transmitted binary data and relays it to the processing module where the received signal is demodulated and communicated to the healthcare specialist device through communication components. The medical instructions from the healthcare specialist are then communicated back to the patient unit through a downlink communication channel of the modules of the system.
The configuration of the system has been optimized by careful choice of the components and their integration by mathematically arriving based on various factors such as delay, distance, illuminance, received power, and angle between transmitter and receiver. The position of the optical transmitters, receivers have been modelled optimally in the various configurations presented by the invention. The system leveraging existing lighting infrastructure has the capability to significantly improve the overall quality of healthcare in healthcare facilities such as but not limited to ICUs and NICUs by enabling seamless collaboration between the healthcare specialists such as doctors and on-site healthcare providers. It also reduces the need for doctors to be physically present in the NICU at all times, allowing them to monitor multiple patients simultaneously and allocate their expertise efficiently. Ultimately, the implementation of the system of the present invention in healthcare facilities such as ICUs enhances patient care, facilitates faster response times, and supports better health outcomes for patients in critical care. The system achieved very high data rates as verified at various distances such as 5 cm, 2 meters etc. confirming its potential for reliable and secure communication in healthcare settings.
Accordingly, the present invention provides a robust VLC system and a method with smart capabilities for effective, accurate and reliable two- way healthcare communication in healthcare facilities such as ICUs or NICUs while being cost effective and ecofriendly.
BRIEF DESCRIPTION OF DRAWINGS
Figure 1a displays detailed communication block diagram between sensed vitals of the incubator to the doctor/ administrator.
Figure 1b Flowchart depicting the VLC communication process.
Figure 2a illustrates Otoroys 14 LED 12V and 42W Power LED, and 2b illustrates S5973 Photodiode for VLC Receiver.
Figure 3 displays architecture 1 - Single transmitter and multiple receivers.
Figure 4 displays architecture 2 – One to one VLC connection.
Figure 5 displays geometry of line of sight (LOS) propagation model.
Figure 6 displays received power distribution (dBm) for architecture 1(One Tx).
Figure 7 displays received power distribution (dBm) for one case of architecture 2 (Two Tx).
Figure 8 displays noise power distribution (dBm) for VLC receiver 1 (Rx1) for a case of architecture 2 (Two Tx).
Figure 9 displays received power distribution (dBm) for architecture 2 (four Tx).
Figure 10 displays noise power distribution (dBm) for Rx 1 in architecture 2.
Figure 11 displays architecture 2: with location coordinates of transmitters and receivers.
Figure 12 displays Opti-system designed block for VLC architecture.
Figure 13 displays eye diagram obtained for Rx1 from Opti-system.
Figure 14 displays eye diagram obtained for Rx2 from Opti-system.
Figure 15 displays designed prototype of VLC transmitter and receiver.
Figure 16 displays delay percentage (%) - transmission signal bit rate (Kbps) graph.
Figure 17 displays phase difference(degrees) between Tx and Rx VS transmission signal bit rate (Kbps) graph.
Figure 18 displays illuminance (lux) versus transmission signal bit rate (Kbps) graph.
Figure 19 displays VLC transmitter rotation procedure.
Figure 20 displays contact angle (degrees) of the Tx - average voltage of received signal (mV) analysis graph.
Figure 21 displays a diffraction angle (degrees) of the light in VLC system.
Figure 22 displays a diffraction angle (degrees) with the change of the transmitter-obstacle distance graph.

DETAILED DESCRIPTION OF THE INVENTION WITH ILLUSTRATIONS AND EXAMPLES
While the invention has been disclosed with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt to a particular situation or material to the teachings of the invention without departing from its scope. However, one of the ordinary skills in art will readily recognize that the present disclosure including the definitions listed here below are not intended to be limited to the embodiments illustrated but is to be accorded with the widest scope consistent with the principles and features described herein.

Throughout the specification and claims, the following terms take the meanings explicitly associated herein unless the context clearly dictates otherwise. The meaning of “a”, “an”, and “the” include plural references. Additionally, a reference to the singular includes a reference to the plural unless otherwise stated or inconsistent with the disclosure herein.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.
A person of ordinary skill in art will readily ascertain that the illustrated steps detailed in the figures and here below are set out to explain the exemplary embodiments shown, and it should be anticipated that ongoing technological development will change the way functions are performed. The examples are presented herein for purposes of illustration, and not limitation. Further, the boundaries of the functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternative boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. Alternatives (including equivalents, extensions, variations, deviations, etc., of those described herein) will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein. Such alternatives fall within the scope and spirit of the disclosed embodiments.

Before discussing example, embodiments in more detail, it is to be noted that the drawings are to be regarded as being schematic representations and elements that are not necessarily shown to scale. Rather, the various elements are represented such that their function and general purpose becomes apparent to a person skilled in the art.

Any connection or coupling between functional blocks, devices, components, or other physical or functional units shown in the drawings or described herein may also be implemented by an indirect connection or coupling. A coupling between components may also be established over a wireless connection. Functional blocks may be implemented in hardware, firmware, software, or a combination thereof.

Further, the flowcharts provided herein, describe the operations as sequential processes. Many of the operations may be performed in parallel, concurrently, or simultaneously. In addition, the order of operations re-arranged. The processes may be terminated when their operations are completed but may also have additional steps not included in the figured. It should be noted, that in some alternative implementations, the functions/acts/ steps noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently, or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

Further, the terms first, second etc… may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers, and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer or section from another region, layer, or a section. Thus, a first element, component, region layer, or section discussed below could be termed a second element, component, region, layer, or section without departing form the scope of the example embodiments.

As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the terms “and/or” and “at least one of” include all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The abbreviations used in the invention are represented in Table 1 as below:
Table 1: Legend of abbreviations
S.no. Particulars Legend
1 Visible Light Communication VLC
2 Optical Wireless Communications OWCs
3 Intensive care unit ICU
4 Neonatal Intensive Care Units NICU
5 Radio frequency RF
6 Line of Sight LOS
7 On-off keying OOK
8 Photodiode PD
9 Medical body area networks MBANs
10 Light emitting diode LED
11 Bit error rate (BER) BER
12 Signal-to-noise ratio SNR
13 Quality of-service QoS
14 Field of view FOV
15 Non-return-to zero NRZ
16 Inter-Symbol Interference ISI
17 Trans impedance amplifier TIA

Some of the technical terms used in the specification are elaborated as below:
RF- restricted health care facilities - It is defined as healthcare facilities that restrict radiofrequency (RF) sources in sensitive areas to prevent accidental interference with medical devices. These areas include the operating theater, neonatal intensive care unit, and intensive care unit.

Patients- A patient is a person who is receiving medical treatment from a doctor or hospital. A patient is also someone who is registered with a particular doctor. A patient here includes men, women, elderly, children, newborn babies etc. any humans who are requiring medical care.

Visible Light Communication- Visible light communication (VLC) is a wireless technology that uses visible light to transmit data at high speeds. It works by adjusting the intensity of light from a source to send data.

Line of sight – In visible light communication (VLC), line-of-sight (LoS) is a requirement for efficient data transmission. LoS is the direct path between a transmitter and a receiver, without any obstacles in the way.

Optical transmitter – In visible light communication (VLC), an optical transmitter is an electro-optical device that converts analog signals from a device like a computer or mobile phone into visible light to transmit data wirelessly.

Optical receiver- In Visible Light Communication (VLC), an optical receiver is a device that converts light signals into electrical signals.

Uplink transmission- Uplink transmission in visible light communication (VLC) is the transmission of data from a VLC end device to a coordinator device. In the present invention the transmission of healthcare parameters from the patient end to the healthcare specialist or doctor end is defined as the uplink transmission.

Downlink transmission - Downlink transmission in visible light communication (VLC) is the process of sending data from a base station to one or more devices. In the present invention the transmission of medical instructions or recommendations from the healthcare specialist or doctor end to the patient end is defined as the uplink transmission.

The reference numerals used in the present invention are tabulated below in Table 2.
Table 2: Legend of Reference numerals
Ser no. Item description Reference numerals
1 System S

2 Patient monitoring module Pa
Patient bed/unit Pa1
Display cum input device Pa2
User interface Pa21

3 Data acquisition module D
Healthcare monitoring sensors D1, D2, D3……

4 Processing module P
First processor board for uplink transmission P1
Demodulator (downlink) P11D
Low pass filter (downlink) P12D
Second processor board for downlink transmission P2
Demodulator (uplink) P21U
Low pass filter (uplink) P22U

5 Transmitter module T
Optical transmitter driver/ controller circuit (uplink, downlink) T1U/T1D
Optical transmitter (uplink/ downlink) T2U/T2D

6 Receiver module R
Optical receivers (uplink, downlink) R1U/R1D
Optical amplifier (uplink, downlink) R2U/R2D
Optical signal concentrator (uplink, downlink) R3U/R3D

7 Healthcare specialist/ doctor/administrator module H
Communication device H1

8 Communication module C
WiFi router C1
Ethernet/ fiber cables C2
Power supply C3

To safeguard patient safety, many healthcare facilities enforce restrictions on the use of mobile phones and RF devices within designated zones. These devices may pose risks due to electromagnetic interference, which can interfere with sensitive medical equipment, potentially compromising its functionality and jeopardizing patient care. This risk is particularly acute for vulnerable populations, such as patients with medical implants and newborns. Newborns, in particular, are highly susceptible to the adverse effects of even minimal exposure to radiofrequency radiation, which can have serious implications for their health and development. Consequently, there is a requirement for healthcare facilities to adopt and implement alternative communication solutions that are both effective and environmentally friendly to ensure a safe and supportive environment for all patients.

Effective health monitoring systems are indispensable in Intensive Care Units (ICUs) and Neonatal Intensive Care Units (NICUs). Premature or critically ill infants admitted to NICUs require constant monitoring for their survival. Continuous and accurate monitoring of vital signs such as heart rate, oxygen saturation, and temperature is essential for early detection of complications. In certain cases, medical professionals may need to remotely monitor vital signs of newborns, especially in cases where limiting direct physical presence is necessary to maintain a sterile and controlled environment. and provide recommendations to on-site healthcare personnel. This highlights the crucial need for secure and reliable communication technologies in healthcare settings, especially those with RF restrictions.

The present invention discloses a system and a method for visible light communication for healthcare facilities as an alternative to RF technology, leveraging visible light for communication of health parameters in healthcare facilities especially that have RF restrictions such as ICU, NICU etc. VLC offers a safe alternative, enabling reliable data transmission without causing disruptions in NICU environments, thereby enhancing patient safety and overall healthcare efficiency. The system also called NeoCommLight is particularly advantageous as it enables simultaneous illumination and communication capabilities in the healthcare facilities. This capability significantly improves the overall quality of healthcare in ICUs, NICUs etc. by enabling seamless collaboration between healthcare specialists (doctors), on site healthcare providers administrators etc. It also reduces the need for the doctors to be physically present in the ICU or NICU at all times, allowing them to monitor multiple patients simultaneously and allocate their expertise efficiently. Ultimately, the implementation of the NeoCommLight system in ICUs or NICUs shall enhance patient care, facilitate faster response times, and support better health outcomes for patients, especially babies in critical care.

The system (S) of the present invention for visible light communication for healthcare facilities, comprises of at least one patient monitoring module (Pa01, Pa02, …, Pan), at least one data acquisition module (D01, D02, …, Dn), at least one processing module (P01, P02, …, Pn), at least one transmitter module (T01, T02, …, Tn), at least one receiver module (R01, R02, …, Rn), at least one healthcare specialist module (H01, H02, …, Hn) and at least one communication module (C01, C02, …, Cn) to provide a robust VLC system with smart capabilities for effective, accurate and reliable two- way healthcare communication in health facilities enabling remote monitoring capabilities while being cost effective and ecofriendly. As per an embodiment of the invention the overall architecture of the system (S) of the present invention is shown in figure 1a and the flowchart depicting the VLC communication process is illustrated in figure 1b. The various modules of the system of the invention are elaborated upon in the following paragraphs.

The patient monitoring module (Pa) of the system facilitates monitoring of health parameters of patients inside the healthcare facilities and comprises of at least one patient bed/unit (Pa101, Pa102, …, Pa1n), associated with each of the patients monitored and at least one display cum input device (Pa201, Pa202, …, Pa2n) for displaying or entering health data and to receive communication from healthcare specialists by healthcare provider at said patient bed /unit (Pa1). The display cum input device (Pa2) comprises of at least one user interface (Pa2101, Pa2102, …, Pa21n), for interfacing and utility by the health provider who is monitoring the patients inside the healthcare facility. The user interface (Pa21) facilitates real time display of health data on the display cum input device (Pa2), allows the health provider to enter health data or health updates and makes accessible the health data of patients through internet, web and mobile applications etc. allowing health specialists, health providers or administrators to receive real-time updates or communicate personalized medical instructions remotely.

The data acquisition module (D) of the system comprises of a plurality of healthcare monitoring sensors (D1, D2, …, Dn), capable of sensing and acquiring health parameters of patients in the form of the health data. The healthcare monitoring sensors (D1, D2, …, Dn) are in plurality with single or combined functionalities selected from group of healthcare sensors such as but not limited to heart rate monitor, temperature monitor, oxygen saturation monitor, Blood Pressure monitor , Carbon Dioxide (CO₂) levels monitor , etc. that provide comprehensive real-time monitoring of vital health parameters, including but not limited to heart rate, temperature, oxygen saturation, blood pressure, any other essential metrics of the patient.
The processing module (P) of the system facilitates processing of the acquired health data for uplink and downlink communication and comprises of at least one first processor board (P101, P102, …, P1n) for communication at the patient bed/unit and at least one second processor board (P201, P202, …, P2n) for communication with healthcare specialists. The first processor board (P1) is connected to the healthcare monitoring sensors (D1) of data acquisition module (D) and the display cum input device (Pa2) of the patient monitoring module (Pa) apart from being connected to the uplink optical transmitter circuit (T1U) and downlink optical amplifier (R2D). The second processor board (P2) of the processor module (P) is connected to communication module (C) apart from being connected to the downlink optical transmitter circuit (T1D) and uplink optical amplifier (R2U).

The processor boards (P1 or P2) are selected from processor units such as but not limited to Raspberry Pi 3 Model B, Raspberry Pi 3 Model B + , Raspberry Pi 3 Model A+, Raspberry Pi 4 Model B Raspberry Pi, Raspberry Pi 3B+ etc. that are capable of converting the health data from data acquisition module (D) or health communication from healthcare specialist module (H) into binary data that is further transmitted to the optical transmitter driver/ controller circuit (T1). The said module comprises of additional components to include at least one demodulator (P11/P21) such as python code and at least one low pass filter (P12/P22) such as MAX7418, MAX7419, MAX7423, LTC1465 etc.

The transmitter module (T) of the system facilitates transmission of the processed health data in the form of optical data and comprises of at least one optical transmitter driver/ controller circuit (T101, T102, …, T1n) each for uplink and downlink communication and at least one optical transmitter (T201, T202, …, T2n) each for uplink communication and downlink communication. The optical transmitter driver/ controller circuit (T1) controls the transmitter circuit and is selected from a group of controller circuits such as, Raspberry Pi 3 Model B + , Otoroys 14 led 12V Light, , 12V battery, MOSFET, N-channel MOSFET 7N60C etc. and a level shifter such as 74HCT125N level shifter may be used for feeding the signal to the controller circuit . The optical transmitter (T2) is utilized to modulate data into optical signals, enabling the wireless transmission of data optically across a medium. A high-power LED is used for optical transmitter (T2) and is connected to the optical transmitter driver/ controller circuit (T1) to emit the blinking visible light or optical signals to communicate the binary data in the uplink transmission from data acquisition module (D) or health communication in the downlink transmission from healthcare specialist module (H). Said high-power LED can be selected from LED, LCD, WS2812 Neo pixel LED, APA102 Dot star LED panel, LW514 LED High Power 3W LED, OTOROYS PowerLED panel etc. Please refer to Figure 2a that displays an OTOROYS PowerLED.

The receiver module (R) of the system facilitates reception of the processed health data in the form of said optical data and comprises of at least one optical receiver (R101, R102, …, R1n) each for uplink and downlink communication, , at least one optical amplifier (R201, R202, …, R2n) to amplify the optical data within optical channel each for uplink and downlink communication making it detectable by the processor module (P) and at least one optical signal concentrator (R301, R302, …, R3n), each for uplink and downlink communication to improve the intensity of optical data. Said optical receiver (R1) is a photodetector that captures said binary data that is in the form of said optical signals from optical transmitter (T2) and is selected from group of large-area, high-sensitive photodiodes such as … SFH203P, SFH229, BPW34, S5973, SFH213., … Hamamatsu S5973 PIN etc. Figure 2b illustrates S5973 Photodiode for VLC Receiver. The optical receiver (R1) converts and transmits optical signals captured into electrical current signal to the processor module (P) where the received signal is demodulated by the demodulator. The optical amplifier (R2) is a dual functioned amplifier that has the capability of converting small current to a voltage from optical receiver (R1) and amplifying to be transmitted to any of the processor boards (P1 /P2). Said dual function amplifier of the receiver module (R) can be selected from Trans impedance amplifier, OPA170 ,OPA 380 Trans impedance amplifier etc.

The healthcare specialist module (H) of the system comprises at least one communication device (H1) utilized by a single or a plurality of healthcare specialists for monitoring health parameters of patients and communicating his/their medical recommendations or instructions remotely.

The communication module (C) of the system facilitates establishing communication of health data of patients being monitored in said healthcare facility with said healthcare specialist module (H) outside the healthcare facility. The communication module (C) comprises of communication means selected from a group of components to include WiFi router, power supply, ethernet/set of fiber cables that enables communication between the healthcare facility and the healthcare specialist.

The system of the present invention is optimally configured and facilitates real time communication of healthcare data of patients to include newborn babies in RF restricted healthcare facilities such as ICUs and NICUs to healthcare specialists placed remotely. It provides a complete two-way visible light communication having both uplink and downlink setup that is applied simultaneously.

As per an embodiment of the invention the system is configured with optical link for uplink communication in the sequence of healthcare monitoring sensors (D1,D2,D3….Dn) at the patient beds/units (Pa1), first processor board (P1) , uplink optical transmitter driver/ controller circuit (T1U), uplink optical transmitters (T2U), uplink optical receiver (R1U), , uplink optical amplifier (R3U), second processor board (P2), and communication device (H1). The optical link for downlink communication is configured in the sequence of communication device (H1), second processor board (P2), downlink optical transmitter driver/ controller circuit (T1D), downlink optical transmitters (T2D), downlink optical receiver (R1D), downlink amplifier (R2D), first processor board (P1) and display cum input device (Pa2) at the patient beds/units( Pa101, Pa102,….Pa10n). The optical communication is line of-sight (LOS) communication wherein optical signals are exclusively focused to ensure direct and unobstructed communication.

As per an embodiment of the invention said system is configured in various architectures. One such architecture is configured with single optical transmitter that is shared between multiple receivers for downlink communication to make the communication set up simple ensuring accurate data transmission with minimal cost. As per another architecture, a one-to-one scheme of VLC communication is facilitated with multiple optical transmitters and optical receivers for direct, efficient and dedicated communication by employing distinct frequency ranges for uplink and downlink communication.

The configuration of the system is optimized mathematically by taking into account important factors such as but not limited to communication delay, the effect of distance on signal quality, and the impact of obstacles on data transmission, interference from ambient light etc. As per one of the configurations of the system optimization of VLC transmission is achieved by positioning uplink optical transmitters (T2U) in the corner of the respective patient beds/units (Pa1) due to the lower ambient noise levels in that area. The downlink optical receivers (R1D) are positioned on the patient units towards the center of the rooms accommodating respective patient beds/units (Pa1) for optimum reception. The optical transmitters (T2D) of the downlink communication are mounted on the ceiling of the room optimized transmission. Optimization is also derived based on the number of patient beds/ units (Pa1) and cost effectiveness.

The method of the present invention facilitates visible light communication for healthcare facilities facilitating two-way communication of health parameters from patient units in the healthcare facilities to healthcare specialists monitoring the patients and communicating instructions remotely. As per the method, health parameters of the patients at each of the plurality of patient units (Pa1) of patient monitoring modules (Pa) in said healthcare facilities are acquired in the form of health data, that are entered by healthcare provider at the patient bed/unit (Pa1) of patient monitoring module (Pa) and transmitted to the processing module (P). The health data is received by a first processing board (P1) in the processing module (P) and processed by converting it into binary data. Said binary data from processor module is received and transmitted in an uplink communication link, wherein said binary data is received by the optical transmitter driver circuit (T2U) of the optical transmitter module (T) and transmitted to the optical transmitter (T1U) in the same module. Next the binary data is converted and emitted in the form of optical signals by said optical transmitter (T1U) of optical transmitter module (T). These optical signals are captured by an optical receiver (R1U) of optical receiver module (R) and are converted and transmitted as electrical current signal to said processor module(P). The current signals are amplified and transformed into voltage signals by optical amplifier (R2U) making it detectable by said processing module(P), an optical signal concentrator (R3U) may be employed to improve the intensity of optical data received by the processor module (P).

The binary data that is in the form of electric voltage signals data is processed by said processor module (P) in steps as follows. This binary data in the form of electric voltage signals is received by a second processor board (P2) in said processor module (P). Here it is demodulated to retrieve back said health data electronically by a demodulator (P21U) in the processor module (P). Said retrieved health data can be filtered using filters such as low pass filters (P22U) to remove any unwanted noise or artifacts. The retrieved health data is then transmitted by the communication module (C) by components such as but not limited to wi-fi router via ethernet connection to communication device (H1) of healthcare specialist module (H).

The system of the invention facilitates two-way communication between the healthcare provider at the patient unit in the healthcare facility and the healthcare specialist who is monitoring remotely the patient at the patient unit. The feedback or medical instructions that the healthcare specialist wishes to communicate with the onsite healthcare provider in the health care facility are done by in a downlink VLC communication link of the system. As per the method of the invention the health communication in the form of feedback or instructions from communication device (H1) of healthcare specialist module (H) is received and transmitted by communication module (C) by components such as but not limited to wi-fi router via ethernet connection to said processor module (P) for onward downlink communication. The health communication is processed by the second processing board (P2) of the processing module (P) by converting it into binary data to obtain processed health communication.

The processed health communication is received from the processing module (P) by an optical transmitter module (T) in a downlink communication the steps of the transmission are as follows. Said health communication is received from the processing module (P) by an optical transmitter driver circuit (T1D) of the optical transmitter module (T) and transmitted to the optical transmitter (T2D) in the same module where it is converted and emitted in the form of optical signals.. Said health communication in the form of optical signals is captured by an optical receiver (R1D) of optical receiver module (R) to be converted and transmitted as electrical current signal to said processor module(P). The current signals are amplified and transformed into voltage signals by optical amplifier (R2U) making it detectable by said processing module(P). An optical signal concentrator (R3D) may be employed to improve the intensity of optical data received by the processor module (P).

Said health communication that is in the form of electric voltage signal is processed by said processor module (P) in the following steps. It is received by the first processor board (P1) in said processor module (P) where it is demodulated to retrieve said health communication electronically by a demodulator (P11D). Said retrieved health communication is filtered using filters such as low pass filters (P12D) to remove any unwanted noise or artifacts and is transmitted to a display cum input device (Pa2) of patient monitoring module (Pa) to be utilized by healthcare provider, associated with patient bed/unit (Pa1) of patient monitoring module (Pa).

The NeoCommLight system of the present invention can be configured in many ways to include two of the following architectures that are optimized to cater for different environments of healthcare facilities such as ICUs or NICUs.

Architecture 1: -
As per an embodiment of the invention, the system can be configured in an architecture with single transistors and multiple receivers for downlink communication. Figure 3 discloses architecture 1 with single transmitter and multiple receivers as described above. This method guarantees that the intended patient/incubator units transmit and receive data in an exact and dependable manner. This setup enables the doctor or the healthcare specialist to access all patient units/ incubators using a single high-power light source.

Synchronization comes to be crucial in such a scenario to ensure smooth and reliable communication. For this purpose, each receiver is assigned a unique identity code such as a 4-bit code scheme before data transmission to reduce inter-communication link interference. The mechanism by which the identity code works to reduce inter-communication link interference comprises of the steps as follows. To overcome the difficulty of identifying data signals for each receiver, the unique code such as 4-bit code is inserted prior to data transmission wherein each receiver awaits the precise 4-bit code assigned to them. The receiver detects and analyses the data signal that follows when it receives the matching 4-bit code. If the transmitted four bits do not match the receiver's assigned code, the receiver continues to monitor the four bits until a match is discovered. To minimize interference in the up-link communication, specific separate time intervals are allocated for each incubator unit. This time division mechanism ensures that the transmissions from different units do not overlap, reducing the risk of signal interference and
maintaining reliable communication.
Architecture 2: -
As per another embodiment of the invention the system can be configured in a second architecture that employs a one-to-one VLC arrangement, with each patient/incubator unit fitted with a dedicated transmitter and receiver module. Each patient/incubator unit has independent transmitter and receiver modules, allowing for direct and dedicated connection between individual transmitter-receiver pairs. This structure allows for a high level of personalization and seclusion for each patient unit/ incubator, adapting to patient demands while also promoting effective communication between healthcare workers and newborns.

Figure 4 illustrates the architecture of such one-to-one VLC arrangements designed specifically for health facilities such as NICUs, where each incubator is equipped with a dedicated VLC transmitter and receiver. To enhance performance, the VLC transmitter is placed in the incubator's corner, where ambient noise levels are lower. Noise distribution calculations in MATLAB demonstrate that corner sections generate less noise than other areas. The yellow beam represents the VLC system downlink, while the blue beam represents the VLC system uplink. This one-to-one communication architecture guarantees that information is transmitted quickly and efficiently.

The NeoCommLight system is exceptional in its technical capabilities when compared to existing solutions, most especially when applied to RF-restricted environments such as NICUs where extensive RF coverage is not possible. This differentiation is achieved through several innovative aspects employed in the invention.
According to an embodiment, the NeoCommLight system using Visible Light Communication (VLC) that is specially designed and developed has the capability to transmit data on relevant vital signs from neonatal units to medical devices used by healthcare professionals, effectively circumventing the problems associated with RF radiation in sensitive environments and successfully moving vital signs data from neonatal units to medical devices.

The system discloses at least two well designed architectures based on transmission accuracy and multi-mode communication (Two-way communication). Architecture 1 includes a VLC communication setup with single transmitter and multiple receivers, which ensures reliable data transmission with minimal interference. It adopts a mechanism of unique code arrangement that ensures accurate and reliable data transmission and reception by the intended incubator units. Moreover, a mathematical model gives the locations of the incubator transmitters with less interference. This level of interference management is crucial in environments where multiple devices operate simultaneously, and it enhances the system's reliability compared to existing methods. The architecture 2 of the NeoCommLight system is a one-to-one two-way communication system with multiple transmitters and receivers. Herein distinct frequency ranges for uplink and downlink communication are employed. Therefore, communication should be more effective.

In the present invention, on the receiving side the amplifiers used are trans-impedance amplifier (OPA 380 Trance Impedance Amplifier (TIA)). The very small photocurrent (pico Ampere range) produced by the photodiode is not suitable for passing directly to the Raspberry Pi GPIO. The current signal needs to be converted to a voltage and then amplified. TIA achieves both requirements, and these typically consist of an operational amplifier (OP-amp) with a feedback resistor back to the inverting input. The band width of this device is 90MHz. That means it can clarify/ detect the signal up to 90Mbps speed. Moreover, for the processing Raspberry Pi has been used which is computationally robust.

The Hamamatsu S5973 PIN photodiode selected for the system is an inexpensive, very sensitive, fast (1GHz) responsivity receiver that is utilized in optical fiber and high-speed photometry applications. This MOSFET helps control the transmitter circuit effectively. N-channel MOSFET 7N60C is used for this system of the invention that is a switching power transistor, for its high current switching capability. The optical signal concentrator (R3) used in the receiver module of the system helps to increase the accuracy of the received signal as well as the communication distance increment.
As per an embodiment of the invention said, the system can transmit data with data rate up to 4 Mbps and the distance to which data is transmitted is up to 3 meters. The system's ability to maintain a data rate of 800 Kbps at a distance of 2 meters, and up to 3 Mbps at shorter distances, showcases its high technical efficiency, particularly in terms of data transmission speed and reliability within the constrained environment of a NICU.
The system has been tested for robust performance across a wide range of conditions, including varying distances, angles, and potential obstacles. The prototype's ability to maintain high data integrity and low error rates under these conditions demonstrates its reliability and effectiveness in real-world applications. This robustness further distinguishes NeoCommLight from other communication systems that may falter under similar conditions.
The system of the present invention, NeoCommLight, uses existing lighting infrastructure for illumination and data transmission, decreasing setup and operational costs by eliminating the need for extra gear. The system's dual functionality, which combines communication and illumination, emphasizes its cost advantages. The NeoCommLight design circuit is affordable compared to the existing design circuits in the VLC industry. The system is also energy-efficient, using up to 90% less energy than typical lighting systems.

The system facilitates the use of minimized wiring and cabling. By replacing traditional wired communication systems with a wireless VLC-based system, NICUs can save substantial wiring. This not only cuts material prices, but it also makes installation easier and decreases labour expenditure. LEDs last longer than conventional lights and electrical components. This lowers maintenance expenses by reducing the frequency of bulb replacements and system repairs.

Investing in future-proof technology such as the present invention in the present times allows healthcare facilities or hospitals to avoid the expenditures involved with replacing obsolete RF systems, which may become less viable as regulatory conditions tighten around RF emissions in sensitive locations such as NICUs. This future proofing guarantees that the initial investment retains its value for an extended length of time, eliminating the need for costly overhauls or replacements. Doctors' capacity to remotely monitor vital signs eliminates the need for continual physical presence in the NICU, allowing healthcare resources to be better allocated. This can save labour costs by requiring fewer people on-site for constant monitoring, and it helps clinicians to manage several cases more effectively.
These economic advantages make the NeoCommLight system a cost-effective and forward-thinking investment for healthcare facilities, particularly those looking to enhance their NICU environments.

This VLC based communication system of the present invention is eco-friendly, safe and provides a supportive environment for patients. We used Visible light range has been used for implementing the communication system. Visible Light Communication (VLC) is considered eco-friendly because it utilizes existing LED lighting infrastructure for data transmission, reducing the need for additional energy-consuming hardware. Unlike traditional RF-based communication systems, VLC does not emit electromagnetic interference, making it safer for healthcare environments, particularly in RF-sensitive zones such as NICUs and operating rooms. Additionally, VLC contributes to energy efficiency by leveraging LEDs, which are already optimized for low power consumption

VLC channel modelling of NeoCommLight system and its analysis
A comprehensive analysis of the optical power distribution and noise distribution about the line-of-sight (LOS) link within the NICU area is provided as follows. Realistic channel modeling and characterization are essential to ensure high quality service (QoS) in communication systems. This is to identify the optimal location coordinates of the VLC transceivers of the NeoCommLight system, for effective transmission of visible light signals, considering the two said architectures explained earlier. For the VLC channel modelling and its analysis, the LED has been selected as the transmitter and the photodiode as the receiver. First, the channel is modelled, then analyzed the distribution of illuminance and noise using MATLAB simulations. The simulations considered various critical variables, such as LED type, LED view angle, the number and positions of LEDs, receiving photodiodes’ characteristics (responsivity, field of view - FOV, active area, and bandwidth), ambient noise, and other relevant parameters. For the indoor VLC system, high-power LEDs are employed as the transmitter source, ensuring robust signal transmission. Additionally, large-area, high-sensitive photodiodes serve as receivers, optimizing the reception of VLC signals as shown in figure 5. In figure 5, Фmax denotes the maximum radiation angle of the transmitting LED concerning the receiving Photodiode. The Ф and d represent the angle of irradiance and the distance between the illuminated surface and the illumination source. The field-of-view (FOV) angle of the photodiode based on its range of view is represented as ΨFOV. Table 3 below illustrates the notations and descriptions as described under this section.
Table 3: Notations and descriptions.
Symbols Parameter
ϕ_max Maximum radiation angle of the transmitting LED
ϕ Angle of irradiance of the transmitting LE
d Distance between the illuminated Transmitter and Receiver
ψ_FOV Field-of-view (FOV) angle of the photodiode
ψ Incident angle
m Lambert’s mode number
R_0 (ϕ) Lambertian radiation intensity
I_S (d,ϕ) Receiver irradiance
P_t Average transmitted optical power
H_LOS LOS channel direct current (DC) gain
A_r Active area of the photodiode
T_s Gain of an optical filter
P_rp Received power in dB
σ_total^2 Total generated noise
σ_shot^2 Shot noise variance
σ_thermal^2 Thermal noise variance
σ_amplifier^2 Noise variance of the amplifier
σ_dc^2 Dark current noise
I_bg Background current which is generated by the other ambient lights
q Charge of the electron
B Bandwidth of the photo-diode
I_2 Noise bandwidth factor
I_a Amplifier's current
B_a Amplifier's bandwidth
I_DC Dark current
R Photodetector responsivity

The radiation pattern of the LED optical transmitter is assumed to be Lambertian. Lambertian radiation intensity distribution in Watt per Steradian (W/Sr) units is calculated based on the equation (1). Lambert’s mode number m is responsible for the directional behavior of the LED source beam. The maximum power is radiated at the angle Ф = 0.
R0(Ф) = ((m + 1)/ 2π) cosm (Ф) −π/2 < Ф < π/2, Ф > π/2 (1)
The Lambertian order m correlated with the semi-radiation angle of the LED as shown in equation (2).
m = −ln (2) / ln (cos (Ф 1/2) (2)
The receiver irradiance, Is (d, Ф) in Watts per Centimeter (W/cm) at d and φ is given in the equation (3), where Pt is the average transmitted optical power and d is the distance across transmitter (Tx) and receiver (Rx).
Is (d, Ф) = PtR0(Ф) / d2 (3)
In the NICU environment, VLC transmitting LEDs are strategically mounted on the ceiling, while photodiodes are precisely positioned on the incubator units, forming the receiving plane. In the NeoCommLight system, the line of sight (LOS) signals is exclusively focused to ensure direct and unobstructed communication. The LOS channel direct current (DC) gain, denoted by HLOS as shown in equation (4), plays a pivotal role in determining the effectiveness of the LOS link. The received power distribution is expressed by equation (6), providing critical insights into the intensity of received VLC signals at different locations.
HLOS = (ArR0(Ф) / d 2) Ts(Ψ)g(Ψ)cos(Ψ) Ψ < Ψ FOV & Ψ > Ψ FOV (4)
Prp = HLOSPt (5)
Prp(dB) = 10log (Prp) (6)
In the given equation, φ = 0 represents the angle of maximum radiated power for the VLC system. The variables, Ar refer to the active area of the photodiode (PD), d denotes the LOS distance between the PD and the LED, and Ts represents the gain of an optical filter, hold crucial significance. These variables collectively contribute to determining the efficiency and performance of the LOS link in the VLC system, aiding in improved signal reception and transmission.
In the context of indoor VLC systems, it is crucial to comprehend the impact of noise on the VLC Line-of-Sight (LOS) channel model. The noise in such systems originates from various sources, which include dark current, thermal noise, amplifier noise, and shot noise. Each of these sources contributes to the overall noise generated by the indoor VLC system. To quantify the total noise generated, σ 2 total, by the system, we have used the below equation,
σ 2 total = σ 2 shot + σ 2 thermal + σ 2 amplifier + σ 2 dc (7)
σ 2 total(dB) = 10log (σ 2 total) (8)
In the equation (7), σ2 shot represents the shot noise variance.
The symbol σ2thermal corresponds to the thermal noise variance and the σ2amplifier represents the noise variance of the amplifier. Finally, the dark current noise is denoted by the σ2dc. The variance of shot noise is given in the equation (9).
σ2 shot = 2qRBPrp + 2qBIbgI2 (9)
It is very crucial to find out the impact of ambient lights on the photodiode to determine the interference it is posing to the actual visible light communication. The background current generated by the other ambient lights is denoted by Ibg as in equation (9). The q represents the charge of the electron and B denotes the bandwidth of the photodiode. The noise bandwidth factor, denoted by the I2, is typically equal to 0.562. The equation (10) allows us to determine the variance of amplifier noise, σ 2 amplifier. The symbol Ia represents the amplifier’s current, and Ba denotes the amplifier’s bandwidth.
σ2amplifier = I2a B2a (10)
σ2dc = 2qBIdc (11)
The dark current noise variance is represented by σ2dc as shown in the equation (11). The Idc represents the dark current, a small amount of electric current generated even in the absence of light. Signal-to-noise ratio (SNR) measures useful information in a noisy environment. In equation (12), the SNR is expressed as a function of the photodetector responsivity R, received optical power, and noise variance.
SNR = (RPrp)2 / σ2total (12)
This study utilizes the equations from (1) to (12) to comprehensively analyze each architecture of the designed system. By applying these equations, the number of VLC transmitters required in any VLC-accessible area can be effectively determined, based on the analysis of received power distribution and noise power distribution.
Analysis of received power distribution for architecture 1: single VLC led transmitter
MATLAB simulations were used to examine the received power distribution for architecture 1 in figure 3, which consists of one LED transmitter and four downlink receivers. The received power distribution is shown in Figure 6. In this setup, the LED is in the centre of the ceiling. This resulted in higher signal reception in the centre, which gradually weakened towards the corners. Based on this discovery, it may be desirable to move the VLC receivers closer to the centre of the room in order to optimize performance. As a result, receivers may see enhanced received power levels, which can contribute to better overall performance. Table 4 shows the simulation settings utilized in the MATLAB simulations for architecture 1.
Table 4: System parameters for received power distribution analysis of VLC architecture 1
Parameters Values
Room Size 5 x 5 x 3m^3
Power of the LED 42W
LED coordinates 2.5,2.5,3
Semi angle of the LED (ϕ) 60^0
Receive plane above the floor 1 m
Active area (AR) 0.01 m^2
Field of view of PD ( ψ_FOV) 70^0
Gain of an optical filter (Ts) 1
Non imaging concentrator gain(g) 1

Analysis of received power and noise distribution for architecture 2: two VLC transmitters
One major feature of this architecture is its inherent redundancy: if one downlink VLC transmitter fails, the second VLC downlink transmitter may still communicate with both VLC receivers. To study the power distribution, MATLAB was used, with the equations mentioned above plotting the received power distribution graph. Despite just having two light beams, the design achieves excellent received power distribution when using LED transmitters. Integrating the individual power distribution statements for Light 1 and Light 2 allows for the drawing of the final power distribution graph for the receiving plane in the room, as shown in Figure 7. This thorough technique allows an informative evaluation of the system's performance and helps to optimize the VLC network for effective communication. The system parameters used in the MATLAB simulation for architecture 2 are provided in Table 5. The connection uses two VLC LED transmitters, and it is critical to consider the impact of ambient noise sources on the communication channel. When VLC transmitter 1 connects with receiver 1, VLC transmitter 2 becomes an ambient noise source, which may impact signal reception. To evaluate the influence of this ambient noise, the noise distribution equation (8) was used in MATLAB to create the noise distribution graph shown in Figure 8. During communication between VLC transmitter 1 and receiver 1, it is critical to treat all other light sources in the vicinity as ambient noise, including VLC transmitter 2. Accurate analysis and visualization of the noise distribution provide valuable insights into the system’s performance and its susceptibility to interference from ambient sources. By understanding the noise distribution, the VLC system’s parameters and configuration can be optimized, ultimately enhancing its reliability and efficiency in real-world scenarios.
Table 5. System parameters of one case of VLC architecture 2
Parameters Values
Room Size 5 x 5 x 3m^3
Power of the LED 42W
LED 1 coordinates -1,0,3
LED 2 coordinates 1,0,3
Semi angle of the LED (ϕ) 60^0
Receive plane above the floor 1 m
Active area (AR) 0.01 m^2
Field of view of PD ( ψ_FOV) 70^0
Gain of an optical filter (Ts) 1
Non imaging concentrator gain(g) 1
Charge of an electron(q) 1.60217663 x 10^(-19)
Bandwidth of the Photodiode (B) 1 GHz
Responsivity of the Photodiode(R) 0.47
Dark current of the photodiode (I_DC) 0.1 nA

Analysis of received power and noise distribution for architecture 2: four VLC transmitters
Figure 4 shows architecture 2, which has four LED transmitters and four independent receivers. Because the four LED transmitters produce different light beams that overlap, environmental noise is considered as a crucial component of VLC transmission. To assess architecture 2's performance, the received power distribution equation (8) was used to create the received power distribution graph in MATLAB, as seen in figure 9. Furthermore, using the system characteristics of VLC architecture 2 as shown in table 6, the noise power distribution graph was generated as shown in figure 10. The investigation revealed that for each transmitter position, the received power on the receiving plane was noticeably high. Finding locations with high received power and less noise was the goal to guarantee dependable connection. The VLC receivers were placed in the incubators' corners based on the power and noise distributions they received. The communication performance and the overall efficiency of the VLC system in this arrangement can be improved by carefully choosing receiver sites that raise the signal-to-noise ratio. The light from the three other LED transmitters in the system is regarded as ambient noise in incubator 1 of architecture 2, where the VLC transmitter (Tx 1) and receiver (Rx 1) are communicating. Equation (8), which accounts for shot noise, amplifier noise, dark current noise, and background noise, was used to create the noise power distribution graph. Equation (9), which represents shot noise, is affected by the plane's received power. Therefore, the combination of the received power distribution from VLC transmitters 2, 3, and 4 determines the noisy power distribution during communication between VLC transmitter 1 and receiver 1. The position coordinates of receiver 1 were set to (1.25, 1.25, 0) to maximize the placement of VLC receivers. Low noise and high received power are the results at that location. Using this method, all additional VLC receivers were positioned thoughtfully at architecture 2 outside corners of each incubator. The VLC system's performance and dependability in incubator 1 will be improved by this methodical receiver configuration, which seeks to optimize signal quality and reduce interference from outside noise sources.
Table 6. System parameters of the VLC architecture 2.
Parameters Values
Room Size 5 x 5 x 3m^3
Power of the LED 42W
LED 1 coordinates -1.25,-1.25,3
LED 2 coordinates 1.25,-1.25,3
LED 3 coordinates -1.25,1.25,3
LED 4 coordinates 1.25,1.25,3
Semi angle of the LED (ϕ) 60^0
Receive plane above the floor 1 m
Active area (AR) 0.01 m^2
Field of view of PD ( ψ_FOV) 70^0
Gain of an optical filter (Ts) 1
Non imaging concentrator gain(g) 1
Charge of an electron(q) 1.60217663 x 10^(-19)
Bandwidth of the Photodiode (B) 1 GHz
Responsivity of the Photodiode (R) 0.47
Dark current of the photodiode (I_DC) 0.1 nA
Amplifier's current (I_a) 2.7 Pa 〖(Hz) 〗^(1/2)
Amplifier's bandwidth (B_a) 90 MHz

VLC interference analysis using Optisystem
The MATLAB simulation results presented in the previous section gave the position of the VLC receivers to achieve high signal quality and less noise. In this part, the Optisystem simulation program was used to examine the interference of the VLC connection if the VLC transmitters and receivers were placed on the geographical coordinates shown in figure 11. A free space optical communication (FSO) connection was designed, tested, and simulated in VLC using Optisystem software. Free-space optical communication (FSO) is a wireless communication technique that uses light in free space to send and receive data. Optisystem uses numerical studies and semi-analytical methods to quantify features like BER (Bit Error Rate) and Q-Factor for systems with inter-symbol interference and noise to ascertain whether the VLC system is optimizing its performance. The design depicted in figure 11 uses Tx1 & Rx1 as one communication channel and Tx2 & Rx2 as another. The light from Tx2 will be background noise if we consider the VLC connection between Tx1 and Rx1. The light from Tx1 will also be considered ambient noise if we consider the transmission between Tx2 and Rx2. The Optisystem model's photodiode and trans-impedance amplifier (TIA) characteristics are chosen based on the photodiode and TIA that were utilized to create the NeoCommLight system. All the settings utilized in this Optisystem simulation are displayed in Table 7. The optical transmitter (T1), FSO link, optical amplifier (R2), optical receiver or photodetector (R1), demodulator, low pass filter, and BER analyzer are the main parts of the FSOL (Free Space Optical Link). Wireless optical data transfer over a medium is made possible by the optical transmitter, usually an LED, which transforms data into optical signals. These signals are then sent via the Free Space Optical (FSO) link. The optical amplifier (R2) is used to enhance the optical data in the FSO channel so that the optical receiver (photodetector) can readily detect it, ensuring dependable and effective data reception. To enable additional processing of the received data, the photodetector—usually a photodiode—captures the incoming optical signal and transforms it into an electrical current signal. The signal needs to be filtered to eliminate any undesired noise or artifacts following demodulation, which involves electrically retrieving the actual data from the carrier wave. In the last stage, the recovered signals are examined by the Bit Error Rate (BER) analyzer, which calculates the BER and measures the precision of the data that was received. An eye diagram, which offers information on the signal quality and aids in maximizing the NeoCommLight system's overall performance, is also displayed by the BER analyzer along with the resultant signal.
Table 7. Optisystem component parameters.
Parameters Values
Input power of Tx1 and Tx2 42W
Semi angle of the LED (ϕ) 60^0
Lambert’s mode number (m) 1
LED frequency 125 GHz
Modulation type NRZ
Gain of the amplifier (TIA) 90 MHz
Amplifier's current (I_a) 3.7 pA
Photodiode Type Silicon
Effective area of the photodiode 0.05 〖mm〗^2
Responsivity of the Photodiode (R) 0.47
Dark current of the photodiode (I_DC) 0.1 nA
Receiver Aperture diameter 1 cm
Distance between TX1 and RX1 2.015564 m
Distance between TX2 and RX2 2.150581 m
Distance between TX1 and RX2 2.66926956301 m
Distance between TX2 and RX1 3.0103989447 m
Angle between Tx2 and Rx1 〖48.36646〗^0
Angle between Tx1 and Rx2 〖41.47293〗^0
Received power of Rx1 because of Tx2 3.2566 x 10^(-7)
Received power of Rx2 because of Tx1 5.2657 x 10^(-7)

Optisystem model: summary and results
Figure 12 depicts a simulation setup for the NeoCommLight system's architecture 2, produced with Optisystem 20. The LED emits an instantaneous white light after converting the data into non-return-to-zero (NRZ) electrical pulses using a pseudo-random data sequence. The modulated output is produced by a high-power white LED with an optical power of 42 W. At room temperature, the high-power white LED and the receiving silicon photodiode create a communication channel through empty space. The parameters of the VLC channel are determined by experimental measurements using free space optics, with just the Line of Sight (LOS) model being considered. This LOS model computes observed FSO parameters. This arrangement assumes all additional sources of ambient light. as noise or interference when VLC transmitted 1 (Tx1) and VLC receiver 1 (Rx1) communicate. Similarly, when VLC receiver 1 and transmitter 1 interact, LED transmitter 2 (Tx2) produces background noise. It was calculated how much power Receiver 1 (PRX1) received from VLC transmitter 2 (Tx2). Furthermore, the equations are utilized to calculate the received power of Receiver 2 (PRX2) from VLC transmitter 1 (Tx1). It was attached to the photodiode as a separate white LED source by an optical coupler. Before connecting the FSO transmission, an optical coupler is utilized to mix the modulated white LED signal with the ambient light.

The eye diagram highlights the effects of Inter-Symbol Interference (ISI) by displaying the responses of 0's and 1's in the received signal, making it a valuable tool for analyzing signal transmission quality. The eye diagram, which depicts signal quality, provides information on the ISI and eye-opening by superimposing plots of the received signal at different symbol times. The opening eye's maximum width represents the appropriate sampling time. Figure 13 depicts an eye diagram for the position of VLC Receiver 1 (Rx1). Figure 14 depicts an eye diagram for the position of VLC Receiver 2 (Rx2). The graphs in this experiment show the received signal quality of Rx1 and RX2. They mix light and noise signals. The system parameters in table 7 and the position coordinates of Tx1, Rx1, Tx2, and Rx2 in the design in figure 15 indicate that the distance between Tx1 and Rx1 is less than that between Tx2 and Rx2. Thus, at Rx1, the received power is more than at Rx2. The larger distance between Tx2 and Rx1 also means that the potential noise power at Rx1 should be lower than at Rx2. Consequently, Rx1 performs better than Rx2. The eye diagram for Rx1 further supports this finding by showing a greater eye-opening size and a higher signal-to-noise ratio (SNR). Rx1 also has a higher quality factor (Q-factor), which reflects SNR quality in the optical signal's "eye." Overall, this simulation demonstrates that Tx1 and Rx1 communication outperforms Tx2 and Rx2 communication. Designers may ensure trustworthy and effective data transfer by adjusting the location coordinates of the NeoCommLight system's transmitters and receivers using the eye diagram and appropriate settings.

Experimental implementation of NeoCommlight system
According to an embodiment of the invention one transmitter and one receiver are used in the NeoCommLight system. The square pulse signal produced by the VLC transmitter is picked up by the VLC receiver. As seen in figure 15, the output of the VLC receiver is fed into an oscilloscope and compared with the signal coming from the VLC transmitter to evaluate the system's performance. The transmitter was a 24 V, 42 W OTOROYS Power LED panel, while the receiver was a Hamamatsu S5973 PIN photodiode. High Power 3W LED has excellent heat dissipation to achieve the benefits of low delay, high luminous efficiency, and long endurance. The LED panels were checked, made with 3W power LEDs. The Otoroys 14 LED (12V) light was selected for the transmitter side of this project. This 12V LED’s angle is 120o and it has 9000 lm illuminance. Its operating voltage is 42W. At 200 cm, this experiment was able to send data at 800 Kbps. The LED panel's luminance decreases when the transmission frequency is increased. This is because higher frequencies need the LED panel to turn on and off more quickly. High frequencies distort the signal, making it hard for the transmitter to provide a VLC signal across long distance. The experiment used a 200-cm transmission distance to evaluate bit rates ranging from 200 bps to 4Mbps. Light intensity diminishes proportionally with distance; hence an optical concentrator is employed at the receiver. The range of the VLC communication system increased from 20 to 200 cm by adding an optical concentrator to the receiver. The received signal was quite identical to the transmitted signal in the low data rate range of 200 bps to 100 Kbps. However, once the data rate approached 100 Kbps, the received signal became visibly distorted. Despite its limited range of 200 cm between transmitter and receiver, the VLC prototype functioned better. The VLC prototype detected a 600 kHz (1.2 Mbps) signal at this distance. When sending a 1.5 MHz (3 Mbps) signal across shorter distances, such as 5 cm, the VLC system operated admirably. We can optimize the VLC circuit design to ensure trustworthy and quick data transfer by understanding the system's strengths and limitations at different frequencies and distances.

Performance evaluation of experimental NeoCommlight system.
The NeoCommLight system prototype's performance is evaluated using characteristics such as the variability of the distance between the transmitter (Tx) and receiver (Rx), communication latency, the average voltage of the received signal, the transmitted source angle, the peak-to-peak voltage of the received signal, transmission bit rate, diffraction angle in the case of a knife edge obstacle, and so on. These qualities were carefully evaluated to guarantee that the system functioned more effectively.
Delay percentage (%) vs. transmission signal bit rate (KBPS) analysis
In addition, the bit-period-to-delay ratio as a percentage estimated and an analysis run. When determining the relationship between the intrinsic bit period and communication delay, this ratio proved critical. The communication latencies or delays (measured in nanoseconds) were then translated to delay percentages using the approach described in equation 13. It is understood that delay is inextricably linked to a bit period and is not only reliant on bit rate. The delay percentage is computed as follows:

Delay Percentage = Delay(ns) × 100% (13)
Bit period
Figure 16 shows a simple graphic that illustrates the relationship between bit rate and delay percentage of received signals. The delay percentage of signals received increases in line with the bit rate. This pattern is especially evident at data rates greater than 200 Kbps. The large discrepancy between high-frequency delays (measured in nanoseconds) and their corresponding bit periods (also measured in nanoseconds) is responsible for the delay percentage spike. Based on the distance provided, it may be concluded that the transmitter has a maximum bit rate that the receiver can detect. For a given transmitter-receiver distance, the receiver cannot detect transmitted data that exceeds the maximum bit rate. This is why the displayed curves are truncated at a specific point, leaving no values.

Phase difference between TX and RX vs. transmission signal bit rate analysis
During the experiments with the NeoCommLight prototype, it was observed that considerable oscillations in the phase angle matched to variations in data rate and distance. The oscilloscope in the prototype monitored the phase difference (in degrees) between transmitted and received signals. Figure 17 depicts the data rate-dependent phase difference between the transmitter (Tx) and receiver (Rx). A magnified phase difference correlates with an increase in bit rate. This phase shift represents the angular offset that the received signal incurred. Furthermore, while the bit rate remains constant, the phase difference increases as the distance between Tx and Rx expands. The phase difference (degrees) between Tx and Rx vs. bit rate (Kbps) plot and the delay percentage (%) vs. bit rate (Kbps) plot are both comparable.
Illuminance (LUX) vs. transmission signal bit rate (KBPS) analysis
Throughout the experiment, there were no barriers between the VLC transmitter and receiver to investigate how lighting varies with transmission signal frequency (bit rate). The lux meter measured the light at the VLC receiver, and the VLC transmitter's data rate was set between 200 bps and 2 Mbps. Figure 18 depicts how illumination varies with transmission bit rate. At close range, the light on the receiver side becomes substantially brighter. Nonetheless, the illuminance drops proportionally as the bit rate rises while the distance stays fixed. The transmitted LED requires more frequent on-off cycles at higher frequencies, which contributes to the loss in brightness at those frequencies. The fluctuation in illumination was less at 50-100 cm than at 1-40 cm. When the receiving side's illumination is higher, the VLC receiver on the NeoCommLight prototype can decode the supplied signal more effectively and correctly. The NeoCommLight system operates effectively in communication, particularly at lower frequencies (bit rates) and greater light levels.

Contact angle (degrees) of the transmitter vs. average voltage of received signal (MV) analysis
The transmission angle is one of the most crucial aspects in pushing the NeoCommLight prototype system to its limits. Figure 19 depicts the method of finding the transmission angle relative to the line of sight (LOS) path between Tx and Rx. The transmitter can rotate clockwise (+θ) or counterclockwise (−θ). The transmission angles employed in this experiment were between -35 and +35 degrees. Figure 20 depicts the connection between the average voltage of the received signal and the transmitting angle. When the VLC transmitter deviates from the line-of-sight location, the average voltage at the VLC receiver varies significantly. When the angle was between -15 and +15 degrees. The average voltage of the received signal is observed to increase. The studies conducted as per the present invention show that the NeoCommLight system's transmitter circuit can efficiently deliver a signal at angles ranging from -15 to 15 degrees from the line of sight. The average voltage of a signal received 50 cm away is higher than that received 150 cm away. When the transmitting angle is 0 degrees, or at line of sight, the average voltage values in Figure 20 are at their highest.

Diffraction angle (degrees) vs. transmitter - obstacle distance
The shadowing effect becomes one of the most serious challenges with VLC since the light signal cannot travel through the solid object. If an obstruction completely blocks the VLC transmission between the transmitter and receiver, the VLC receiver will be unable to decode the supplied data. For this experiment, a solid object of 20 × 20 x 1 cm3 was employed with the VLC Tx and Rx situated 100 cm away. 50% of the VLC broadcast was blocked by positioning the solid item within 100 cm of the transmitter and receiver. Diffraction of the light beam was detected after inserting a barrier between the VLC transmission. Figure 21 shows how diffraction causes light to gently bend as it passes through an object's edge. The diffraction angle changes when the obstacle alters in the VLC transmission route. The oscilloscope was used on the receiver side to determine the average voltage of the received signal. Table 8 shows the voltage of the received signal at various transmitter-obstacle distances. Light transmission occurs in three dimensions in real-world circumstances. This experiment was carried out horizontally to make the diffraction effect more easily illustrated. Because of the low communication distance, horizontal or vertical alignment will make little impact. When the blockage was between 1 and 40 cm from the transmitter, low average received signal voltages were discovered. The average voltage received when the impediment was between 50 and 80 cm was 1.6 V, which was the same as when the obstacle was not there. This implies that the 50% obstruction does not affect VLC transmission when positioned between 50 and 80 cm from the transmitter. The prototype experiment's design evaluates a maximum signal reception distance of two meters. The NICU unit may be seen from the ceiling at no more than two meters. Therefore, it is seen that the reflected signal is more than two meters away from the receiver. As a result, the reflected signal is very weak and inconsequential at the receiver. Furthermore, the positioning of the transceivers impacts interference. The transceivers must be properly positioned based on an examination of the received power distributions and noise power. Reflection is thus not an option in this experiment. Figure 22 shows how the diffraction angle (in degrees) varies with the distance between the transmitter and the barrier. As the distance between the transmitter and the obstruction increases, the diffraction angle decreases exponentially.
The experiment also showed that there is no visible change in the diffraction angle while the transmitted light bit rate is adjusted. As a result, it may be concluded that the transmitted bit rate and diffracted angle have no relationship. At a certain distance, the diffraction angle becomes zero, indicating that the obstruction has no influence on visible light transmission.

Table 8. Variability of average received signal voltage (mV) in the presence of the obstacle
Transmitter to obstacle distance (cm) Average received signal voltage (mV)
1 862
10 890
20 884
30 886
40 909
50 1617.5
60 1620
70 1618
80 1531.4

The system’s performance analysis showed that it could transmit data up to 3 Mbps within a two-meter range. Then the following summarizes the interpretations of the performance analysis. The NeoCommLight prototype could transmit a signal with a bandwidth of 800 Kbps at a maximum distance of 200 cm. In addition to this, the prototype could transmit the data with a data rate of 3 Mbps at a distance of 5 cm from the receiver. As the transmission bit rate increases, the delay percentage in the received signals linearly increases. This trend becomes prominent when the transmission signal bit rates surpass 200 Kbps. The phase difference between the transmitted and received signal increases with an increase in the Tx-Rx distance while maintaining the same bit rate. At lower transmission bit rates, the illuminance is higher, and thereby the receiving efficiency of the NeoCommLight system is also high compared to the higher transmission bit rates. When the transmitter contact angle is between −15 and +15 degrees, an increase in the average voltage of the received signal was observed. When the obstacle is placed in the range of 50 cm to 80 cm from the transmitter, the average received voltage obtained is 1.6 V, which is the same value we obtained without the obstacle. When the obstacle is between 1 cm and 40 cm from the transmitter, low average signal voltages are received at the VLC receiver. The diffraction angle (due to the placement of the obstacle between the transmitter and receiver) decreases exponentially as the distance between the transmitter and the obstacle increases. There are no significant changes in the diffraction angle concerning the change in the bit rate of the transmitted light.
EXAMPLES
The present invention shall now be explained with accompanying examples. These examples are non-limiting in nature and are provided only by way of representation. While certain language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be seeming to a person skilled in the art, various working alterations may be made to the method in order to implement the inventive concept as taught herein. The figures and the preceding description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, order of steps of method or processes of data flow described herein may be changed and is not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts need to be necessarily performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.

In an exemplary embodiment, the various hardware, devices and software which together form the system (S) along with the working of the invention and the method thereof are illustrated below.

Hardware
Display cum input device to provide system status and real-time monitoring interface, such as, Raspberry Pi display unit, LCD unit, etc.
Healthcare monitoring sensors such as heart rate monitor, temperature monitor, oxygen saturation monitor, Blood Pressure monitor, Carbon Dioxide (CO₂) levels monitor ………., etc.
Processor board acts as the main processing unit for encoding and modulating signals for uplink/ receiving optical signals and decoding transmitted data downlink transmission such as Raspberry Pi, Raspberry Pi 3 Model B, Raspberry Pi 3 Model B +, Raspberry Pi 3 Model A+, Raspberry Pi 4 Model B raspberry pi 3B+.
Optical transmitter driver/ controller circuit such as MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor- used for high-speed switching of the LED light source), MOSFET 7N60C.
Level shifter that converts voltage levels between Raspberry Pi and MOSFET for proper signal transmission and ensures proper voltage compatibility between receiver components, such as level 74HCT125N shifter.
Optical transmitter that are high-power white LEDs capable of intensity modulation for VLC. such as LED, LCD, WS2812 Neo pixel LED, APA102 Dot star LED panel, LW514 LED High Power 3W LED, OTOROYS PowerLED panel etc.
Optical receivers or photodetector, that captures modulated light signals, such as Photodiode (PIN Photodiode or Avalanche Photodiode), SFH203P, SFH229, BPW34, S5973, SFH213, Hamamatsu S5973 PIN etc.
Optical amplifier that converts low-amplitude photodetector signals into usable electrical signals- OPA 380 Transimpedance Amplifier (TIA).
Low pass filter such as MAX7418, MAX7419, MAX7423, LTC1465 etc.
Optical signal concentrator, WiFi router, Ethernet/ fiber cables, Power supply
Software
User interface such as python based, or JAVA based visualization software on Raspberry Pi display unit.
Demodulator or decoder such as a python code.
Modulation & Encoding – Supports OOK (On-Off Keying), PPM (Pulse Position Modulation), or OFDM (Orthogonal Frequency Division Multiplexing) for VLC signal transmission.
Firmware Development Tools – Raspberry Pi OS, Python for programming and communication control.

Best mode of the working of the invention
NeoCommLight system
According to an embodiment, the system of the invention, the NeoCommLight system, comprises a Raspberry Pi module, photodiode, LCD, and healthcare monitoring sensors, providing comprehensive real-time monitoring of vital parameters, including heart rate, temperature, oxygen saturation, blood pressure, and other essential metrics.

On the transmitter side, the user needs to enter the data in the form of text signal that needs to be transmitted. The Raspberry Pi module acts as the primary processing unit or the processing board (P1/P2) of the processing module (P), effectively translating measured parameters into binary data. Raspberry pi 3B+ (Microcontroller), used in the present embodiment, converts that text signal to the binary format (1s and 0s). The Raspberry pi 3B+ board generates the transmitted pulse signal. The Raspberry pi output signal is not directly applied to MOSFET that controls the transmitter circuit as it is compatible with an input voltage signal of up to 5V. Therefore, the pulse signal or frequency signal is given to a level shifter, level 74HCT125N shifter, that shifts this signal to the 5V range. Once the voltage is shifted the signal can be sent to the MOSFET. N-channel MOSFET 7N60C is used in the present embodiment of the invention. It is a switching power transistor and is chosen for its high current switching capability. It can handle a current of 14A and 600V and its switching time is 45ns.

The binary values from the processor module(P) are then sent to the LED driver circuit, which activates a high-power LED attached to the incubator, resulting in flickering visible light signals. High Power 3W LED has excellent heat dissipation to achieve the benefits of low delay, high luminous efficiency, and long endurance. Accordingly, the Otoroys 14 LED (12V) light is selected for the transmitter side of this invention. This 12V LED’s angle is 120o and it has 9000 lm illuminance while its operating voltage is 42W. Separate VLC transmitter and receiver module for each patient unit is provided that assists in reducing the interference and maintaining the line of site. Figure 4 illustrates the architecture of a one-to-one VLC system designed specifically for NICUs, where each incubator is equipped with a dedicated VLC transmitter and receiver. To optimize performance, the VLC transmitter is positioned in the corner of the incubator, taking advantage of the lower ambient noise levels in that area. The one-to-one communication design ensures a highly efficient transmission of information providing benefits including rapid decision-making and improved healthcare outcomes.
In the receiving mode, the photodiode captures the transmitted binary data light signal. The Hamamatsu S5973 PIN photodiode selected is a low-cost, high sensitivity, high-speed (1GHz) responsivity that is used in high-speed photometry applications and in optical fiber applications. It comes in a TO-18 kit and operates at +3.3V. The S5973 series operates across the necessary spectral range (320nm-1000nm) and is suitable for optical use with a peak sensitivity of around 760nm.

A trans impedance amplifier (OPA 380) amplifies the current signal and converts it into the voltage signal by transforming it. The very small photocurrent produced by the photodiode is not suitable for passing directly to the Raspberry Pi GPIO. It needs to be converted to a voltage and amplified. The OPA380 trance impedance amplifier could achieve both requirements, and they typically consist of an operational amplifier (op-amp) with feedback resistor back to the inverting input. A feedback capacitor can also be utilized to prevent gain peaks, depending on the terminal capacitance of the connecting photodiode. The few parameters to adjust and adapt to the circuit to link the trans-impedance amplifier include the feedback resistor, the feedback capacitor, and, if needed, any resistor biasing.

Since the voltage level shifter (74HCT125N) was used to shift the voltage up to 5V and this voltage level cannot be fed directly to the raspberry pi board as it is possible that it might damage the Raspberry pi board. Therefore 3.3V Zener diode is used to regulate the voltage level up to 3.3 V.
Therefore, in the receiving mode, the VLC receiving circuit collects the sent binary data and sends it to Raspberry Pi module (P) for demodulation. After that, the raspberry pi board detects the signal and decodes it to the original message signal and displays it on the screen.

The VLC module placed on the roof rail of the NeoCommLight system comprises of the Raspberry Pi module (P) connected to a Wi-Fi router via high-speed Ethernet or Fiber connections, other than the LED and Photodiode circuits. This allows doctors to access patient records seamlessly through the Internet. Doctors and administrators can remotely monitor each incubator from any location worldwide, facilitating timely and informed medical decisions. This proposed method is two-way communication. The doctors can provide specific instructions to the individual NICU units based on the received sensor parameters. The recommended instructions are promptly displayed on each unit’s monitor, streamlining the workflow for nurses and promoting efficient implementation.

The system’s user-friendly interface, accessible through web and mobile applications, allows doctors and administrators to access patient data, set instructions, and receive real-time updates effortlessly, even if they are not physically present in the NICU area. The block diagram of the NeoCommLight system as described above is displayed in figure 1a that shows the system modules for the two-way communication of the sensor values/vital parameters and the instructions from the incubator unit to the doctor outside the NICU area.

, Claims:We claim:
1. A system (S) for visible light communication for healthcare facilities, said system (S) comprising of :-
- at least one patient monitoring module (Pa01, Pa02, …, Pan), that facilitates monitoring of health parameters of patients inside the healthcare facilities, said patient monitoring module (Pa1) comprising of
• at least one patient bed/unit (Pa101, Pa102, …, Pa1n) associated with each of the patients monitored and
• at least one display cum input device (Pa201, Pa202, …, Pa2n) for displaying or entering health data and to receive communication from healthcare specialists by healthcare provider, associated with said patient bed /unit (Pa1),
- at least one data acquisition module (D01, D02, …, Dn), said data acquisition module (D) comprising of at least one healthcare monitoring sensor (D1, D2, …, Dn), capable of sensing and acquiring health parameters of patients in the form of the health data,
- at least one processing module (P01, P02, …, Pn) to facilitate processing of the acquired health data for uplink and downlink communication, said processing module (P) comprising of
• at least one first processor board (P101, P102, …, P1n) for communication at the patient bed/unit and
• at least one second processor board (P201, P202, …, P2n) for communication with healthcare specialists,
- at least one transmitter module (T01, T02, …, Tn), for transmission of the processed health data in the form of optical data, said transmission module (P) comprising of
• at least one optical transmitter driver/ controller circuit (T101, T102, …, T1n) each for uplink and downlink communication and
• at least one optical transmitter (T201, T202, …, T2n) each for uplink communication and downlink communication,
- at least one receiver module (R01, R02, …, Rn), for reception of the processed health data in the form of said optical data, said receiver module (R) comprising of
• at least one optical receiver (R101, R102, …, R1n) each for uplink and downlink communication,
• at least one amplifier (R201, R202, …, R2n) to amplify the optical data within optical channel each for uplink and downlink communication making it detectable by the processing module (P) and
• at least one optical signal concentrator (R301, R302, …, R3n), each for uplink and downlink communication to improve the intensity of optical data,
- at least one healthcare specialist module (H01, H02, …, Hn), said healthcare specialist module (H) comprising of at least one communication device (H1) utilized by a healthcare specialist for monitoring health parameters of patients and communicating remotely,
- at least one communication module (C01, C02, …, Cn) for establishing communication of health data of patients being monitored in said healthcare facility with said healthcare specialist module (H) outside the healthcare facility,
wherein
- said system is optimally configured and facilitates real time communication of healthcare data of patients to include newborn babies in healthcare facilities such as ICUs and NICUs to healthcare specialists placed remotely,
- said system is configured for a complete two-way visible light communication having both uplink and downlink setup that is applied simultaneously,
- said system is configured wherein the optical link for uplink communication is in the sequence of healthcare monitoring sensors (D1,D2,D3….Dn) at the patient beds/units (Pa1), first processor board (P1) , uplink optical transmitter driver/ controller circuit (T1U), uplink optical transmitters (T2U), uplink optical receiver (R1U), , uplink optical amplifier (R2U), optical concentrator (R3U), second processor board (P2), and communication device (H1),
- said system is configured wherein the optical link for downlink communication is in the sequence of communication device (H1), second processor board (P2), downlink optical transmitter driver/ controller circuit (T1D), downlink optical transmitters (T2D), downlink optical receiver (R1D), downlink optical amplifier (R2D), optical concentrator (R3D), first processor board (P1) and display cum input device (Pa2) at the patient beds/units( Pa101, Pa102,….Pa10n),
- said configuration of the system is optimized mathematically by taking into account factors such as but not limited to communication delay, the effect of distance on signal quality, and the impact of obstacles on data transmission, interference from ambient light etc.,
- said system is configured in at least one architecture with single optical transmitter that is shared between multiple receivers for downlink communication to make the communication set up simple ensuring accurate data transmission with minimal cost,
- said system is configured in at least one architecture for a one-to-one scheme with multiple optical transmitters and optical receivers for direct, efficient and dedicated communication by employing distinct frequency ranges for uplink and downlink communication,
- said configuration is optimised by positioning uplink optical transmitters (T2U) in the corner of the respective patient beds/units (Pa1) due to the lower ambient noise levels in that area,
- said configuration is optimised by positioning downlink optical receivers (R1D) positioned on the patient units towards the centre of the rooms accommodating respective patient beds/units (Pa1) for optimum reception,
- said configuration is optimised by positioning optical transmitters (T2D) of the downlink communication mounted on the ceiling of the room,
- said configuration is optimised based on number of patient beds/ units (Pa1) and cost effectiveness and
- said optical amplifier (R3) is a dual functioned amplifier that has the capability of converting small current to a voltage from optical receiver (R1) and amplifying to be transmitted to any of the processor boards (P1 /P2)
to provide a robust VLC system with smart capabilities for effective, accurate and reliable two- way healthcare communication in healthcare facilities enabling remote monitoring capabilities while being cost effective and ecofriendly.
2. The system as claimed in claim 1, wherein said display cum input device (Pa2) comprises of at least one user interface (Pa2101, Pa2102, …, Pa21n), for interfacing and utility by the health provider who is monitoring the patients inside the healthcare facility.
3. The system as claimed in claim 2, wherein said user interface (Pa21) facilitates real time display of health data on the display cum input device (Pa2), allows the health provider to enter health data or health updates and makes accessible the health data of patients through internet, web and mobile applications etc. allowing health specialists, health providers or administrators to receive real-time updates or communicate personalized medical instructions remotely.
4. The system as claimed in claim 1, wherein said healthcare monitoring sensors (D1, D2, …, Dn) are in plurality with single or combined functionalities selected from group of healthcare sensors such as but not limited to heart rate monitor, temperature monitor, oxygen saturation monitor , Blood Pressure monitor, Carbon Dioxide (CO₂) levels monitor, etc. , providing comprehensive real-time monitoring of vital health parameters, including but not limited to heart rate, temperature, oxygen saturation, blood pressure, any other essential metrics of the patient.
5. The system as claimed in claim 1, wherein said processing module (P) comprises of additional components to include at least one demodulator such as a python code and at least one low pass filter selected from group of MAX 7418, MAX7419, MAX7423, LTC1465 etc.
6. The system as claimed in claim 1, wherein said processor boards (P1 or P2) is selected from processor units such as but not limited to Raspberry Pi 3 Model B, Raspberry Pi 3 Model B + , Raspberry Pi 3 Model A+, Raspberry Pi 4 Model B .Raspberry Pi, Raspberry Pi 3B+, preferably Raspberry Pi 3B+ that is capable of converting the health data from data acquisition module (D) or health communication from healthcare specialist module (H) into binary data that is further transmitted to the optical transmitter driver/ controller circuit (T1).
7. The system as claimed in claim 1, wherein said optical transmitter driver/ controller circuit (T1) controls the transmitter circuit and is selected from a group of controller circuits such as, Raspberry Pi 3 Model B + , Otoroys 14 led 12V Light, 12V battery… MOSFET, N-channel MOSFET 7N60C etc. preferably N-channel MOSFET 7N60C and a level shifter such as 74HCT125N level shifter may be used for feeding the signal to the controller circuit.
8. The system as claimed in claim 1, wherein said Display cum input device (Pa2) is selected from group of display units such as Raspberry Pi display unit, LCD unit, etc and User interface (Pa21) is selected from group of visualization software such as python based or JAVA based visualization software.
9. The system as claimed in claim 1, wherein said transmitter module (T) employs modulation & encoding that supports schemes such as OOK (On-Off Keying), PPM (Pulse Position Modulation), or OFDM (Orthogonal Frequency Division Multiplexing) for VLC signal transmission.
10. The system as claimed in claim 1, wherein said processing module (P) utilizes Firmware development tools such as but not limited to Raspberry Pi OS, python for programming and communication control etc.
11. The system as claimed in claim 1, wherein said optical transmitter (T2) is a high-power LED connected to the optical transmitter driver/ controller circuit (T1) and emits the blinking visible light or optical signals to communicate the binary data in the uplink transmission from data acquisition module (D) or health communication in the downlink transmission from healthcare specialist module (H).
12. The system as claimed in claim 11, wherein said high-power LED is selected from LED, LCD WS2812 Neo pixel LED, APA102 Dot star LED panel, LW514 LED, High Power 3W LED, OTOROYS PowerLED panel preferably OTOROYS PowerLED panel.
13. The system as claimed in claim 1, wherein said optical receiver (R1) captures said binary data that is in the form of said optical signals from optical transmitter (T2) and is a photodetector selected from group of large-area, high-sensitive photodiodes such as SFH203P, SFH229, BPW34, S5973, SFH213, Hamamatsu S5973 PIN etc. preferably Hamamatsu S5973 PIN photodiode.
14. The system as claimed in claim 1, wherein said optical receiver (R1) converts and transmits optical signals captured into electrical current signal subsequently to the processor module (P) where the received signal is demodulated by the demodulator.
15. The system as claimed in claim 1, wherein said optical amplifier (R2) can be augmented with devices such as but not limited to feedback resistor, feedback capacitor, resistor biasing, Zener diode as per the optical circuit requirements.
16. The system as claimed in claim 1, wherein said first processor board (P1) of the processor module (P) is connected to the healthcare monitoring sensors (D1) of data acquisition module (D) and the display cum input device (Pa2) of the patient monitoring module (Pa) apart from being connected to the uplink optical transmitter circuit (T1U) and downlink optical amplifier (R2D).
17. The system as claimed in claim 1, wherein said communication module (C) comprises of communication means selected from a group of components to include WiFi router, power supply, ethernet/set of fiber cables that enables communication between the healthcare facility and the healthcare specialist.
18. The system as claimed in claim 1, wherein said second processor board (P2) of the processor module (P) is connected to the components of communication module (C) such as a Wi-Fi router via high-speed Ethernet or fiber cables apart from being connected to the downlink optical transmitter circuit (T1D) and uplink optical amplifier (R2U).
19. The system as claimed in claim 1, wherein said optical amplifier (R3) that acts as a dual functioned amplifier of the receiver module (R) is Trans impedance amplifier, OPA 380 Trance Impedance Amplifier (TIA), OPA170 etc. preferably OPA 380 Trance Impedance Amplifier.
20. The system as claimed in claim 1, wherein said optical communication is line of-sight (LOS) communication wherein optical signals are exclusively focused to ensure direct and unobstructed communication.
21. The system as claimed in claim 1, wherein said system can transmit data with data rate up to 4 Mbps and the distance to which transmission is done is up to 3 meters.
22. The system as claimed in claim 1, wherein said architecture with single transistor and multiple receivers for downlink communication is configured to assign each receiver a unique identity code before data transmission to reduce inter-communication link interference, preferably a 4-bit code scheme.
23. The system as claimed in claim 22, wherein said identity code is worked to reduce inter-communication link interference in a mechanism the steps comprising of
- introducing and assigning a 4-bit code scheme to the respective optical receivers (R1) before data transmission,
- monitoring and waiting by each optical receiver (R1) for its assigned 4-bit code until it matches and
- decoding the transmitted signal by optical receiver (R1) when the received signal matches its assigned code while the other optical receivers (R1) remain inactive and wait for their respective assigned codes.
24. The system as claimed in claim 22, wherein said architecture employs a time division mechanism to minimize interference in the up-link communication by allocating specific separate time intervals for each patient unit.
25. A method for visible light communication for healthcare facilities facilitating two-way communication of health parameters from patient units in the healthcare facilities to healthcare specialists monitoring the patients and communicating instructions remotely wherein said method comprises of steps of
- acquiring of health parameters of the patients at each of a plurality of patient units (Pa1) of patient monitoring module (Pa) in said healthcare facilities, in the form of health data,
- entering of said health data by healthcare provider at the patient bed/unit (Pa1) of patient monitoring module (Pa) and transmitting it to a processing module (P),
- receiving and processing of the health data by a first processing board (P1) in the processing module (P) by converting it into binary data,
- receiving and transmitting said binary data from processing module (P) by an uplink communication link the steps comprising of
• receiving said binary data from processing module (P) by an optical transmitter driver circuit (T2U) of an optical transmitter module (T) and transmitting it to the optical transmitter (T1U) in the same module,
• converting and emitting said binary data in the form of optical signals by said optical transmitter (T1U) of optical transmitter module (T),
• capturing the binary data that is in in the form of said optical signals by an optical receiver (R1U) of optical receiver module (R) and converting to current signals,
• amplifying the current signals and transforming to voltage signals by optical amplifier (R2U) making it detectable by said processing module(P) and
• improving the intensity of optical data received by the processor module (P) by employing optical signal concentrator (R3U),
- processing of binary data that is in the form of electric voltage signals by said processor module (P) in steps comprising of
• receiving said binary data that is in the form of electric voltage signal by a second processor board (P2) in said processor module (P),
• demodulating said binary data that is in the form of electric voltage signal to retrieve back said health data electronically by a demodulator (P21U) in the processor module (P) and
• filtering of said retrieved health data using filters such as low pass filters (P22U) to remove any unwanted noise or artifacts,
- transmitting the retrieved health data by wi-fi router via ethernet connection of communication module (C) to communication device (H1) of healthcare specialist module (H),
- receiving and transmitting health communication in the form of feedback or instructions from communication device (H1) of healthcare specialist module (H) by wi-fi router via ethernet connection of communication module (C) to said processor module (P) for onward downlink communication,
- processing of the health communication by the second processing board (P2) of the processing module (P) by converting it into binary data to obtain processed health communication,
- receiving said processed health communication from the processing module (P) by an optical transmitter module (T) in a downlink communication link the steps of transmission in said downlink communication link comprising of,
• receiving said health communication from the processing module (P) by an optical transmitter driver circuit (T1D) of the optical transmitter module (T) and transmitting it to the optical transmitter (T2D) in the same module,
• converting and emitting said health communication in the form of optical signals by said optical transmitter (T2D) of the optical transmitter module (T),
• capturing said health communication in the form of said optical signals by an optical receiver (R1D) of optical receiver module (R) to be converted and transmitted into electrical current signal to said processor module(P),
• amplifying the current signals and transforming to voltage signals by optical amplifier (R2U) making it detectable by said processing module(P) and
• improving the intensity of optical data received by the processor module (P) by employing optical signal concentrator (R3U)
- processing of health communication that is in the form of electric voltage signal by said processor module (P) in steps comprising of
• receiving said health communication that is in the form of electric voltage signal by the first processor board (P1) in said processor module(P),
• demodulating said health communication that is in the form of electric voltage signal to retrieve back said health communication electronically by a demodulator (P11D) in the processor module(P) and
• filtering of said retrieved health communication using filters such as low pass filters (P12D) to remove any unwanted noise or artifacts and
- transmitting the retrieved health communication to a display cum input device (Pa2) of patient monitoring module (Pa) to be utilized by healthcare provider, associated with patient bed/unit (Pa1) of patient monitoring module (Pa).
26. The system as claimed in claim 1, wherein said system (S) has practical applications in healthcare facilities to include facilities such as ICUs, NICUs etc.

Dated this the 11th day of April 2025
________________________
Daisy Sharma
IN/PA-3879
of SKS Law Associates
Attorney for the Applicant
To
The Controller of Patents
The Patent Office, Chennai