Claims:1. A system (100) for node-based data acquisition, the system comprising:
one or more sensor elements (102) that receive a set of signals;
an acoustic node (104) coupled to each of the one or more sensor elements (102), the acoustic node converts the received set of signals to digital set of signals, wherein the acoustic node performs framing to generate a first set of data packets, the first set of data packets pertaining to acoustic data;
a non-acoustic node (106) configured in the system, the non- acoustic node generates second set of data packets, wherein the second set of data packets pertaining to any or a combination of depth data and direction data; and
a processor (112) coupled to the acoustic node (104) and the non-acoustic node (104), the processor configured to:
receive, from the acoustic node (104), the first set of data packets;
receive, from the non-acoustic node (106), the second set of data packets;
validate the first set of data packets and the second set of data packets of the corresponding nodes, and
generate, from the validated data an output set of signals, wherein the processor is configured to analyse the output set of signals of the corresponding nodes.
2. The system as claimed in claim 1, wherein the one or more sensor elements (102) comprises radially polarized hydrophone (202) and triplet hydrophone (204).
3. The system as claimed in claim 1, wherein pre-amplifier printed circuit board (PCB) coupled to the one or more sensor elements (102), the pre-amplifier PCB adapted to pre-amplify the set of signals and convert the set of signals as differential output signal.
4. The system as claimed in claim 1, wherein the acoustic node (104) comprises analogue PCB and digital PCB, wherein the analogue PCB receives the set of signals from the pre-amplifier PCBs of the one or more sensor elements.
5. The system as claimed in claim 1, wherein the processor (112) groups the acoustic data based on the radially polarized hydrophone (202) and triplet hydrophone (204), wherein the processor performs fast Fourier transform (FFT) on the validated data.
6. The system as claimed in claim 1, wherein the non-acoustic node (106) coupled to one or more sensors, the one or more sensors comprises a depth sensor (110) and a direction sensor (108), wherein the non-acoustic node (106) receives the depth data from the depth sensor and receives direction data from the direction sensor.
7. The system as claimed in claim 6, wherein the non-acoustic node (106) converts the captured direction data and depth data into digitized data to generate the second set of data packets.
8. The system as claimed in claim 1, wherein the system (100) comprises graphical user interface (GUI) to select any or a combination of acoustic node and non-acoustic node to perform validation and to display the validated data.
9. The system as claimed in claim 1, wherein the first set of data packets and the second set of data packers are in a combination of local area network (LAN) format.
10. A method (400) for node-based data acquisition, the method comprising:
receiving (402), at one or more sensor elements, a set of signals;
converting (404), at an acoustic node, the received set of signals to digital set of signals, wherein the acoustic node performs framing to generate a first set of data packets, the first set of data packets pertaining to acoustic data, the acoustic node coupled to each of the one or more sensor elements;
generating (406), at a non-acoustic node, a second set of data packets, wherein the second set of data packets pertaining to any or a combination of depth data and direction data;
validating (408), at a computing device, the received first set of data packets and second set of data packets of the corresponding nodes; and
generating (410), at the computing device, from the validated data an output set of signals, wherein, the computing device configured to analyse the output set of signals of the corresponding nodes.
, Description:TECHNICAL FIELD
[0001] The present disclosure relates, in general, to data acquisition and monitoring system, and more specifically, relates to a system and method for linear acoustic and non-acoustic data acquisition and monitoring.

BACKGROUND
[0002] The gathering of data in an acoustic environment using an array of electrically interconnected hydrophones is important for commercial and military purposes. Few existing technologies in the field of underwater trailing sensors include programmable data collection and a relay circuit for a towed hydrophone array. The circuit is designed to prepare data concerning the operation of the array to be interleaved with substantive data produced by the hydrophones to produce a single data stream for transmission to recording equipment. The circuit comprises a plurality of sensor inputs, each of the sensor inputs adapted to be coupled to a sensor capable of sensing a physical characteristic within the towed hydrophone array, a circuit for polling at least a portion of the plurality of sensor inputs to determine values of the inputs, a circuit for storing programmed data concerning which of the plurality of inputs is to be polled and a circuit for serially placing the input values in condition for insertion into a data stream transmitted along the towed hydrophone array.
[0003] Another existing technology relates to signal processing for signal reception and parameter estimation. The existing technology has many applications such as frequency estimation, filtering and array data processing. The array processing problem addressed is that of signal parameter and waveform estimation utilizing data collected by an array of sensors. The sensor array geometry and individual sensor characteristics need not be known. However, the sensors must occur in pairs such that the paired elements are identical except for a displacement which is the same for all pairs. These element pairs define two sub-arrays, which are identical except for a fixed known displacement. However, these existing technologies suffer from limitations of analogue signal conditioning for each sensor were being processed by common digital hardware on a time-multiplexed basis with increased wiring connections.
[0004] Therefore, there is a need in the art to provide a means that enables an effective method for data acquisition, monitoring and validating the output of the underwater linear acoustic device using a dedicated digital node for a group of sensor elements resulting in reduced wiring connections, easy fault detection and localization.

OBJECTS OF THE PRESENT DISCLOSURE
[0005] An object of the present disclosure relates, in general, to data acquisition and monitoring system, and more specifically, relates to a system and method for linear acoustic and non-acoustic data acquisition and monitoring.
[0006] Another object of the present disclosure is to provide a system that provides node-based data acquisition to reduce the wiring requirements significantly compared to multiplexed analogue signal acquisition.
[0007] Another object of the present disclosure is to provide a system that enables fault detection and localization up to sensor level.
[0008] Another object of the present disclosure reduces the noise and improves the SNR due to the reduced wiring and reduction in analogue wiring path length.
[0009] Another object of the present disclosure is to provide a system that enables to display the processed data from the selected node.
[0010] Another object of the present disclosure is to provide a system that analysis for both linear and triplet housing of the sensor elements.
[0011] Yet another object of the present disclosure allows the easy expansion of system to monitor higher number of elements used in linear array.

SUMMARY
[0012] The present disclosure relates, in general, to data acquisition and monitoring system, and more specifically, relates to a system and method for linear acoustic and non-acoustic data acquisition and monitoring. The present disclosure has a dedicated digital node for acoustic sensor elements and common digital hardware for direction and depth sensor data acquisition and monitoring.
[0013] In an aspect, the present disclosure provides a system for node-based data acquisition, the system includes one or more sensor elements that receive a set of signals, an acoustic node coupled to each of the one or more sensor elements, the acoustic node converts the received set of signals to digital set of signals, wherein the acoustic node performs framing to generate a first set of data packets, the first set of data packets pertaining to acoustic data, a non-acoustic node configured in the system, the non- acoustic node generates second set of data packets, wherein the second set of data packets pertaining to any or a combination of depth data and direction data, a processor coupled to the acoustic node and the non-acoustic node, the processor configured to receive, from the acoustic node, the first set of data packets, receive, from the non-acoustic node, the second set of data packets, validate the first set of data packets and the second set of data packets of the corresponding nodes, generate, from the validated data an output set of signals wherein, the processor configured to analyse the output set of signals of the corresponding nodes.
[0014] In an embodiment, the one or more sensor elements may include radially polarized hydrophone and triplet hydrophone.
[0015] In another embodiment, the pre-amplifier printed circuit board (PCB) coupled to the one or more sensor elements, the pre-amplifier PCB adapted to pre-amplify the set of signals and convert the set of signals as differential output signal.
[0016] In another embodiment, the acoustic node may include analogue PCB and digital PCB, wherein the analogue PCB receives the set of signals from the pre-amplifier PCBs of the one or more sensor elements.
[0017] In another embodiment, processor may group the acoustic data based on the radially polarized hydrophone and triplet hydrophone, wherein the processor performs fast Fourier transform (FFT) on the validated data.
[0018] In another embodiment, the non-acoustic node coupled to one or more sensors, the one or more sensors comprises depth sensor and direction sensor, wherein the non-acoustic node receives the depth data from the depth sensor and receives direction data from the direction sensor.
[0019] In another embodiment, the non-acoustic node converts the captured direction data and depth data into digitized data to generate the second set of data packets.
[0020] In another embodiment, the system comprises graphical user interface (GUI) to select any or a combination of acoustic node and non-acoustic node to perform validation and to display the validated data.
[0021] In another embodiment, the first set of data packets and the second set of data packers are in a combination of local area network (LAN) format.
[0022] In an aspect, the present disclosure provides a method for node-based data acquisition, the method including receiving, at one or more sensor elements, a set of signals, converting, at an acoustic node, the received set of signals to digital set of signals, wherein the acoustic node performs framing to generate a first set of data packets, the first set of data packets pertaining to acoustic data, the acoustic node coupled to each of the one or more sensor elements, generating, at a non-acoustic node, a second set of data packets, wherein the second set of data packets pertaining to any or a combination of depth data and direction data, validating, at a computing device, the received first set of data packets and second set of data packets of the corresponding nodes, and generating, at the computing device, from the validated data an output set of signals, wherein the computing device configured to analyse the output set of signals of the corresponding nodes.
[0023] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.
[0025] FIG. 1A illustrates an exemplary block diagram of the linear acoustic array and monitoring system, in accordance with an embodiment of the present disclosure.
[0026] FIG. 1B illustrates an exemplary view of main hydrophone node assembly, in accordance with an embodiment of the present disclosure.
[0027] FIG. 1C illustrates an exemplary view of triplet node assembly, in accordance with an embodiment of the present disclosure.
[0028] FIG. 1D illustrates an exemplary view of non-acoustic assembly, in accordance with an embodiment of the present disclosure.
[0029] FIG. 2 illustrates an exemplary view of data flow for visualizing the device data for monitor and analysis, in accordance with an embodiment of the present disclosure.
[0030] FIG. 3A illustrates an exemplary view of acoustic data calibration in GUI, in accordance with an embodiment of the present disclosure.
[0031] FIG. 3B illustrates an exemplary view of non-acoustic data calibration in GUI, in accordance with an embodiment of the present disclosure.
[0032] FIG. 4 illustrates an exemplary flow diagram of method for node-based data acquisition, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0033] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0034] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0035] The present disclosure relates, in general, to data acquisition and monitoring system, and more specifically, relates to a system and method for linear acoustic and non-acoustic data acquisition and monitoring. The present disclosure has a dedicated digital node for acoustic sensor elements and common digital hardware for direction and depth sensor data acquisition and monitoring.
[0036] Underwater trailing sensors are effective in detecting and finding faint objects usually which are quiet, low noise emitting contacts. The underwater tail layout provides superior resolution and measurement data as compared to sensors which are fit to the frame of the vessel. The device for locating sources of underwater sound is placed at a specific distance along the guided elements to triangulate the source of the sound. Likewise, various elements are angled down which gives the ability to estimate the depth of the contact. The operational status of the underwater sensor device in terms of sampled data and its corresponding energy distribution as a function of frequency for a particular sound source can be visualized. Along with this, non-acoustic information regarding the direction, displacement, and extent of distance downwards for the entire housing elements can be visualized. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.
[0037] FIG. 1A illustrates an exemplary block diagram of the linear acoustic array and monitoring system, in accordance with an embodiment of the present disclosure.
[0038] Referring to FIG. 1A, data acquisition and monitoring system 100 (also referred to as system 100, herein) may be configured for data acquisition, monitoring and validating the output of the underwater linear acoustic device. System 100 may include one or more sensor elements 102, where the one or more sensor elements 102 may include main hydrophone assembly (202-1 to 202-N as illustrated in FIG. 1B and described in detail below), triplet hydrophone assembly (204-1, 204-2, 204-3 as illustrated in FIG. 1C and described in detail below). Further, system 100 may include acoustic node assembly 104, a depth sensor 110, direction sensor 108, non-acoustic node assemblies 106 and a processor 112.
[0039] In an embodiment, one or more sensor elements 102 may receive the acoustic data and can provide the analogue electric signal to the acoustic node assembly 104 also interchangeably referred to as acoustic node hardware 104. The acoustic node hardware 104 may perform the signal conditioning, framing of data in local area network (LAN) format. The LAN data may be analysed and suitably represented on monitoring software for further validation. The direction and depth sensor data may be captured by non-acoustic node 106 and digitized data in LAN format can be provided to monitoring software. These sensors (108, 110) may be used to determine the shape distortion of the linear array.
[0040] FIG. 1B illustrates an exemplary view of main hydrophone node assembly, in accordance with an embodiment of the present disclosure. The main hydrophone assembly (202-1 to 202-N (which are collectively referred to as main hydrophone assembly 202, hereinafter)) may include hydrophone mechanical housing that may include single-channel pre-amplifier PCB and radially polarized hydrophone elements connected in parallel. The pre-amplified data (also interchangeably referred to as a pre-amplified set of signals) from the single-channel pre-amplifier PCB may be converted as a differential output signal and sent to acoustic node 104.
[0041] FIG. 1C illustrates an exemplary view of triplet node assembly, in accordance with an embodiment of the present disclosure. The triplet hydrophone assembly (204-1, 204-2, 204-3 (which are collectively referred to as triplet hydrophone assembly 204, hereinafter)) may include triplet hydrophone housing that may include a dual-channel pre-amplifier PCBs and three hydrophone elements mounted at 120º apart from each other as shown in FIG. 1C. The triplet hydrophone assembly 204 may resolve left/right ambiguity. The pre-amplified data from the dual-channel pre-amplifier PCBs can be converted as a differential output signal and sent to the acoustic node 104.
[0042] In another embodiment, the acoustic node assembly 104 is the stack of analogue and digital node PCB. The data from the analogue PCB flows to the digital PCB over a high-density connector and the control signals from the digital PCB flows to the analogue card over the same high-density connector. In an exemplary embodiment, due to the size constraint of towed array diameter number of channels is restricted to 9 channels. The current wiring assembly implementation has been carried out for 9 sensor elements 102. As can be appreciated, the present disclosure may not be limited to this configuration but may be extended to other configurations such that for enhanced wiring assembly the implementation can be scaled further.
[0043] In another embodiment, the analogue PCB of acoustic node 104 may be capable of receiving outputs from 9 pre-amplifier PCBs. The analogue PCB may include a programmable gain amplifier (PGA), anti-aliasing filter and fixed gain amplifier sections. The PGA may receive the gain control word from the digital PCB. The digital PCB of the acoustic node 104 may receive the 9 channel’s signal conditioned output. The signal conditioned output may be fed to the analogue to digital converters (ADCs). The ADCs may include a serial peripheral interface (SPI) interface to provide the sampled data.
[0044] The analogue signal received from one or more sensor elements 102 may be immediately digitised and data frames are formed and sent to the next stage through Ethernet packets. This node-based data acquisition may provide the advantage of better fault localisation up to the sensor level. Each node PCB is configured with internet protocol version 4 (IPv4) address with help switch settings, using the IP address of node PCBs, the monitoring software can select the node and view the required sensor data providing better fault detection and fault localisation.
[0045] FIG. 1D illustrates an exemplary view of the non-acoustic assembly, in accordance with an embodiment of the present disclosure. The non-acoustic data from direction sensor 108 and from the depth/pressure sensor 110 may be carried through the non-acoustic node 106 and digitised, which is further through the Ethernet switch may be sent to the processing software as shown in FIG.1D. The direction sensor 108 and the depth/pressure sensor 110 are coupled to the non-acoustic node 106. In an exemplary embodiment, the direction sensor 108 may be a heading/rolling sensor. Depth sensor data and direction data i.e., heading/rolling data may be digitized and one digital output may be routed for processing.
[0046] In an implementation, one or more sensor elements 102 may receive the set of signals (also interchangeably referred to as analogue signals). The acoustic node 104 coupled to each of the one or more sensor elements 102, the acoustic node 104 may convert the received set of signals to a digital set of signals. The acoustic node 104 may perform framing to generate the first set of data packets, where the first set of data packets pertaining to acoustic data. The non-acoustic node 106 configured in system 100, the non-acoustic node 106 may generate the second set of data packets pertaining to any or a combination of depth data and direction data. The non-acoustic node 106 may be coupled to the one or more sensors (108, 110) and may combine any or a combination of depth data and direction data to generate the second set of data packets. The first set of data packets and the second set of data packets may be in the combination of LAN format.
[0047] In another embodiment, the processor 112 coupled to the acoustic node 104 and the non-acoustic node 106. The processor 112 configured to receive, from the acoustic node 104, the first set of data packets and receive, from the non-acoustic node 106, the second set of data packets. Processor 112 may validate the first set of data packets and the second set of data packets of the corresponding nodes. The processor 112 may generate, from the validated data an output set of signals, where the processor 112 configured to analyse the output set of signals of the corresponding nodes. The output set of signals may be frequency component which can be used for spectrum analysis.
[0048] For example, the digital node may receive the differential signal from one or more sensor elements 102 and may perform the signal conditioning actions such as pre-amplifications, filtering, analogue to digital conversion. The digital data may be stored on a system-on-chip memory for further framing and packet transmission. These packets may be received by validating software/processor 112 for acoustic data monitoring and validating the output. For each of the sourced element, sampled data at a designated time interval is analysed by plotting as signal potential difference v/s timed sample, signal strength v/s frequency.
[0049] The application software may be capable of monitoring the device’s entire housing including its individual element. Selection of the different elements, nodes is also possible which helps in comparative analysis and localizing the behaviour. The underwater sensor device may transmit the analogue data to the circuitry board which may digitize the data by conversion. It also stores a certain number of samples for each element. These data are precisely framed in accordance with the factor as identified in the samples and transmitted for data representation. Ideally, the housing of the device is linear. However, the device when placed in its operational environment may be subjected to displacements and this may affect the data representation and its correctness. Hence, these parameters such as direction, displacement, and extent of distance downwards can also be represented to implement the corrections.
[0050] The embodiments of the present disclosure described above provide several advantages. The one or more of the embodiments provides node-based data acquisition that can reduce the wiring requirements significantly compared to multiplexed analogue signal acquisition. The present disclosure enables fault detection and localization up to the sensor level. The reduced wiring and reduction in analogue wiring path length may reduce the noise and improves the signal to noise ratio (SNR). The graphical user interface (GUI) of the data acquisition and monitoring system 100 has provision for the acoustic node selection and may display the processed data from the selected node. This method allows the easy expansion of system 100 to monitor the higher number of elements used in the linear array.
[0051] FIG. 2 illustrates an exemplary view of data flow 200 for visualizing the device data for monitor and analysis, in accordance with an embodiment of the present disclosure.
[0052] Referring to FIG. 2, the data (also interchangeably referred to as data packets) can be received from the linear acoustic array in the time interval-based frames for further processing. The data can be grouped and segregated based on the housing devices, which may help in easier data representation. For example, the processor 112 may group the acoustic data based on the radially polarized hydrophone 202 and triplet hydrophone 204, where the processor 112 may perform FFT on the validated data. In the UI, there may be a provision to select the device’s nodes, e.g., acoustic node, and non-acoustic node so that validation may be performed appropriately. The sampled data is subjected to the low pass filter (LPF), where the parameters can be carefully chosen to reconstruct the sinusoidal wave.
[0053] The waveform may be depicted as one element in case of linear housing whereas it may be depicted as three in case of triplet housings. The output of LPF is subjected to FFT algorithm, where depending upon the FFT size, data can be accumulated and the inverse time component based on the bins can be calculated. The output set of signals may be frequency component, which can be used for spectrum analysis.
[0054] In another embodiment, each acoustic sensor housing has the pre-amplifier PCB to amplify the received signal, the output of 9 such pre-amplifier PCBs are fed to the acoustic node 104 PCB for filtering and digitisation purpose. The analogue signal received from the sensor is immediately digitised and data frames are formed and sent to the next stage through Ethernet packets. This node-based data acquisition reduces wiring requirement in the array drastically as the data are relayed over to the next stage using common Ethernet. The current wiring assembly, implementation has been carried out for 9 sensor elements 102. However, with enhanced wiring assembly the implementation can be scaled further. In another embodiment, due to the digitization of sensor outputs at the location, the number of connection is reduced to 1/3rd of analogue connections. Previously, the data connector of 160 pins used at the end of array modules is reduced to 36 pin connectors.
[0055] The node-based data acquisition and data transfers using the Ethernet lane allow the modular expansion method for the array. With the use of a set of electronics and sensors, the towed array can be designed as per the resolution or number of channels requirements of the sonar. The new sensor elements and corresponding node PCBs are connected to the existing Ethernet network.
[0056] In another embodiment, system 100 may provide improved SNR. Since the node-based data acquisition has reduced wiring requirement and the analogue data captured and digitised immediately, the travel path of the analogue signal has reduced significantly and can provide improvement in SNR as illustrated in table 1.

IMPROVEMENT IN SNR DUE TO NODE BASED IMPLMENTATION
Parameter Digital Node (Current Implementation) Analogue Format
OBSERVED RMS NOISE ((in mVolts) 100 70
OBSERVED RMS NOISE ((in Volts) 0.1 0.07
RMS SIGNAL LEVEL (in Volts) 2.5 2.5
SNR (in dB) 27.95880017 31.05684
IMPROVEMENT IN SNR (in dB) 3.0980392
Table 1: Improvement in SNR due to node-based implementation
[0057] FIG. 3A illustrates an exemplary view of acoustic data calibration 300 in GUI, in accordance with an embodiment of the present disclosure. FIG. 3A depicts the plotting of acoustic data as received by the one or more sensor elements 102.
[0058] FIG. 3B illustrates an exemplary view of non-acoustic data calibration in GUI, in accordance with an embodiment of the present disclosure. FIG. 3B depicts the non-acoustic data representation that may include the depth data and the directional data.
[0059] FIG. 4 illustrates an exemplary flow diagram of method for node-based data acquisition, in accordance with an embodiment of the present disclosure.
[0060] The method 400 can be implemented using a computing device, which can include one or more processors. The method 400 incudes, at block 402 one or more sensor elements may receive a set of signals, at block 404, acoustic node may convert the received set of signals to digital set of signals, where the acoustic node may perform framing to generate a first set of data packets, the first set of data packets pertaining to acoustic data. The acoustic node coupled to each of the one or more sensor elements.
[0061] At block 406, non-acoustic node may generate a second set of data packets, where the second set of data packets pertaining to any or a combination of depth data and direction data. At block 408, the computing device may validate the received first set of data packets and second set of data packets of the corresponding nodes. At block 410, computing device may generate from the validated data an output set of signals, where the computing device configured to analyse output set of signals of the corresponding nodes.
[0062] It will be apparent to those skilled in the art that the system 100 of the disclosure may be provided using some or all of the mentioned features and components without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the scope of the disclosure, as described in the claims.

ADVANTAGES OF THE PRESENT DISCLOSURE
[0063] The present disclosure provides a system that provides node-based data acquisition to reduce the wiring requirements significantly compared to multiplexed analogue signal acquisition.
[0064] The present disclosure provides a system that enables fault detection and localization up to sensor level.
[0065] The present disclosure reduces the noise and improves the SNR due to the reduced wiring and reduction in analogue wiring path length.
[0066] The present disclosure provides a system that enables to display the processed data from the selected node.
[0067] The present disclosure allows the easy expansion of system to monitor higher number of elements used in linear array.
[0068] The present disclosure provides a system that analysis for both linear and triplet housing of the sensor elements.