FIELD OF THE PRESENT DISCLOSURE
[0001] The present disclosure generally relates to warehouse management and
particularly to signalling systems, such as pick-to-light (PTL) units, in a warehouse. More specifically, the present disclosure relates to systems and methods for managing a plurality of pick-to-light (PTL) units in a warehouse to handle communication for operational optimisation in a warehouse.
BACKGROUND
[0002] In traditional warehouses, an order is fulfilled by sending a copy of an order
for a specific item or group of items to an operator. The operator by reference to a facility map or plan must identify the location of the item, go to that location, pick the required quantity of items for the order, and place them in an appropriate receptacle. This process is repeated until a given order is filled. This is error-prone, e.g., selecting from an incorrect, but adjacent shelf or other storage receptacle, to picking the wrong quantity of the correct item, or to putting the correct items in an incorrect receptacle for subsequent shipping or order processing. Further, such system may not be able to process batch order, resulting in significant inefficiencies associated with repeated trips to pick each order individually.
[0003] Nowadays, order fulfilment warehouses, such as distribution centres for e-
commerce companies, rely upon a signalling system employing pick-to-light (PTL) units in order to direct an operator to where the pick or put is to occur, in order to provide for better efficiency and accuracy. The PTL unit can include alphanumeric and coloured information that is located at the particular destination to inform and guide the operator. A warehouse management system (WMS) keeps track of the inventory and the orders to be filled and is integrated with the signalling system to direct the pick or put operation and to receive confirmation of its completion. Such system attempts to direct operators in an optimal sequence to the location of each item in an inventory. Electronically transmitted picking information may be sent to one or more operators

and in return, real-time picking information such as failure to complete the order from the operators, may provide means for the control and verification of the entire process.
[0004] For such purposes, the PTL units need to have a proper communication
channel with respective controllers and an uninterrupted power supply. Traditionally, the warehouses have a certain number of PTL units connected in a daisy chain manner (serial) to a controller, such as a gateway. Typically, the warehouses use Ethernet to RS-485 gateway (as known in the art) from third-party companies to which PTL units are connected. Conventionally, such communication from between the PTL units and the gateway takes place over two data cables. Further, the power required for operations of the PTL units is supplied via two additional wires meant for power transmission. Thereby, a conventional setup may require at least four wires for purposes of proper communication and power supply. This adds to installation and commissioning, time and cost.
[0005] Therefore, in light of the foregoing discussion, there exists a need to overcome
problems associated with conventional systems and methods for configuring the PTL units in a warehouse for reducing installation and commissioning, time and cost therefor.
SUMMARY
[0006] In an aspect, a system for managing a plurality of pick-to-light (PTL) units in
a warehouse is provided. The system comprises a controller in signal communication with a server to receive data packets to be transmitted to the plurality of PTL units. The system also comprises a power supply configured to provide DC power for operation of each of the plurality of PTL units. The system further comprises a power line communication arrangement. The power line communication arrangement comprises a bus connection comprising two wires. The power line communication arrangement also comprises a first transceiver associated with the controller to receive the data packets therefrom and coupled to the bus connection. The first transceiver is configured to modulate the received data packets with a carrier signal to generate a high frequency clock signal to be transmitted over the two wires in the bus connection. The power line communication arrangement further comprises a first series inductances associated with the controller and coupled to the bus connection. The first series inductances is configured to couple

the DC power from the power supply to be transmitted over the two wires in the bus connection. The power line communication arrangement further comprises a second transceiver associated with one of the plurality of PTL units and coupled to the bus connection. The second transceiver is configured to demodulate the high frequency clock signal to extract the data packets therefrom to be processed by the said one of the plurality of PTL units. The power line communication arrangement further comprises a second series inductances associated with the said one of the plurality of PTL units and coupled to the bus connection. The second series inductances is configured to decouple the DC power from the bus connection to be supplied to a load of the said one of the plurality of PTL units.
[0007] In one or more embodiments, the power line communication arrangement
further comprises a first series capacitances associated with the controller and coupled to the bus connection. The first series capacitances is configured to couple the high frequency clock signal from the first transceiver to the bus connection.
[0008] In one or more embodiments, the power line communication arrangement
further comprises a second series capacitances associated with the said one of the plurality of PTL units and coupled to the bus connection. The second series capacitances is configured to decouple the high frequency clock signal from the bus connection to be utilized by the said one of the plurality of PTL units.
[0009] In one or more embodiments, the carrier signal has a frequency at least ten
times higher than a frequency of the received data packets.
[0010] In one or more embodiments, the first transceiver and the second transceiver
implement On-off keying (OOK) modulation scheme.
[0011] In one or more embodiments, the bus connection comprises a diode bridge to
supply a same polarity of the DC power to the load of the said one of the plurality of PTL units as the received DC power therein.
[0012] In another aspect, a method for managing a plurality of pick-to-light (PTL)
units in a warehouse is provided. The method comprises receiving, by a controller, data packets from a server to be transmitted to the plurality of PTL units. The method further comprises providing a bus connection comprising two wires, to couple a first transceiver and a first series

inductances associated with the controller, and a second transceiver and a second series inductances associated with one of the plurality of PTL units. The method further comprises modulating, by the first transceiver, the received data packets with a carrier signal to generate a high frequency clock signal. The method further comprises coupling, by the first series inductances, DC power from a power supply to be transmitted over the two wires in the bus connection. The method further comprises demodulating, by the second transceiver, the high frequency clock signal to extract the data packets therefrom to be processed by the said one of the plurality of PTL units. The method further comprises decoupling, by the second series inductances, the DC power from the bus connection to be supplied to a load of the said one of the plurality of PTL units.
[0013] In one or more embodiments, the bus connection further couples a first series
capacitances associated with the controller and a second series capacitances associated with the said one of the plurality of PTL units. Herein, the method further comprises coupling, by the first series capacitances, the high frequency clock signal from the first transceiver to the bus connection; and decoupling, by the second series capacitances, the high frequency clock signal from the bus connection to be transmitted to the said one of the plurality of PTL units.
[0014] In one or more embodiments, the method further comprises implementing the
carrier signal having a frequency at least ten times higher than a frequency of the received data packets.
[0015] In one or more embodiments, the method further comprises configuring the
first transceiver and the second transceiver to implement On-off keying (OOK) modulation scheme.
[0016] The foregoing summary is illustrative only and is not intended to be in any
way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE FIGURES
[0017] For a more complete understanding of example embodiments of the present

disclosure, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:
[0018] FIG. 1 illustrates a system that may reside on and may be executed by a
computer, which may be connected to a network, in accordance with one or more exemplary embodiments of the present disclosure;
[0019] FIG. 2 illustrates a diagrammatic view of a server device, in accordance with
one or more exemplary embodiments of the present disclosure;
[0020] FIG. 3 illustrates a diagrammatic view of a client device, in accordance with
one or more exemplary embodiments of the present disclosure;
[0021] FIG. 4 illustrates a diagrammatic arrangement of a rack in a warehouse with
a plurality of PTL units installed therein, in accordance with one or more exemplary embodiments of the present disclosure;
[0022] FIG. 5 illustrates a schematic detailed circuit diagram of a system for
managing a plurality of PTL units in a warehouse, in accordance with one or more exemplary embodiments of the present disclosure; and
[0023] FIG. 6 illustrates a flowchart listing steps involved in a method for managing
a plurality of PTL units in a warehouse, in accordance with one or more exemplary embodiments of the present disclosure.
DETAILED DESCRIPTION
[0024] In the following description, for purposes of explanation, numerous specific
details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent, however, to one skilled in the art that the present disclosure is not limited to these specific details.
[0025] Reference in this specification to "one embodiment" or "an embodiment"
means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. The appearance of the phrase "in one embodiment" in various places in the specification are not necessarily all

referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Further, the terms "a" and "an" herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not for other embodiments.
[0026] Furthermore, in the following detailed description of the present disclosure,
numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be understood that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the present disclosure.
[0027] Embodiments described herein may be discussed in the general context of
computer-executable instructions residing on some form of computer-readable storage medium, such as program modules, executed by one or more computers or other devices. By way of example, and not limitation, computer-readable storage media may comprise non-transitory computer-readable storage media and communication media; non-transitory computer-readable media include all computer-readable media except for a transitory, propagating signal. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or distributed as desired in various embodiments.
[0028] Some portions of the detailed description that follows are presented and
discussed in terms of a process or method. Although steps and sequencing thereof are disclosed in figures herein describing the operations of this method, such steps and sequencing are exemplary. Embodiments are well suited to performing various other steps or variations of the steps recited in the flowchart of the figure herein, and in a sequence other than that depicted and described herein. Some portions of the detailed descriptions that follow are presented in terms of procedures, logic blocks, processing, and other symbolic representations of operations on data bits within a computer memory. These descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art.

In the present application, a procedure, logic block, process, or the like, is conceived to be a self-consistent sequence of steps or instructions leading to a desired result. The steps are those utilizing physical manipulations of physical quantities. Usually, although not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as transactions, bits, values, elements, symbols, characters, samples, pixels, or the like.
[0029] In some implementations, any suitable computer usable or computer readable
medium (or media) may be utilized. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer-usable, or computer-readable, storage medium (including a storage device associated with a computing device) may be, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable medium may include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fibre, a portable compact disc read-only memory (CD-ROM), an optical storage device, a digital versatile disk (DVD), a static random access memory (SRAM), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, a media such as those supporting the internet or an intranet, or a magnetic storage device. Note that the computer-usable or computer-readable medium could even be a suitable medium upon which the program is stored, scanned, compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory. In the context of the present disclosure, a computer-usable or computer-readable, storage medium may be any tangible medium that can contain or store a program for use by or in connection with the instruction execution system, apparatus, or device.
[0030] In some implementations, a computer readable signal medium may include a
propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. In some implementations, such a propagated signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination thereof. In some implementations, the computer readable program code may be

transmitted using any appropriate medium, including but not limited to the internet, wireline, optical fibre cable, RF, etc. In some implementations, a computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.
[0031] In some implementations, computer program code for carrying out operations
of the present disclosure may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Java®, Smalltalk, C++ or the like. Java and all Java-based trademarks and logos are trademarks or registered trademarks of Oracle and/or its affiliates. However, the computer program code for carrying out operations of the present disclosure may also be written in conventional procedural programming languages, such as the "C" programming language, PASCAL, or similar programming languages, as well as in scripting languages such as JavaScript, PERL, or Python. In present implementations, the used language for training may be one of Python, Tensorflow™, Bazel, C, C++. Further, decoder in user device (as will be discussed) may use C, C++ or any processor specific ISA. Furthermore, assembly code inside C/C++ may be utilized for specific operation. Also, ASR (automatic speech recognition) and G2P decoder along with entire user system can be run in embedded Linux (any distribution), Android, iOS, Windows, or the like, without any limitations. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the internet using an Internet Service Provider). In some implementations, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGAs) or other hardware accelerators, micro-controller units (MCUs), or programmable logic arrays (PLAs) may execute the computer readable program instructions/code by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present disclosure.

[0032] In some implementations, the flowchart and block diagrams in the figures
illustrate the architecture, functionality, and operation of possible implementations of apparatus (systems), methods and computer program products according to various implementations of the present disclosure. Each block in the flowchart and/or block diagrams, and combinations of blocks in the flowchart and/or block diagrams, may represent a module, segment, or portion of code, which comprises one or more executable computer program instructions for implementing the specified logical function(s)/act(s). These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the computer program instructions, which may execute via the processor of the computer or other programmable data processing apparatus, create the ability to implement one or more of the functions/acts specified in the flowchart and/or block diagram block or blocks or combinations thereof. It should be noted that, in some implementations, the functions noted in the block(s) may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.
[0033] In some implementations, these computer program instructions may also be
stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks or combinations thereof.
[0034] In some implementations, the computer program instructions may also be
loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed (not necessarily in a particular order) on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts (not necessarily in a particular order) specified in the flowchart and/or block diagram block or blocks or combinations thereof.
[0035] Referring now to the example implementation of FIG. 1, there is shown a

system 100 that may reside on and may be executed by a computer (e.g., computer 12), which may be connected to a network (e.g., network 14) (e.g., the internet or a local area network). Examples of computer 12 may include, but are not limited to, a personal computer(s), a laptop computer(s), mobile computing device(s), a server computer, a series of server computers, a mainframe computer(s), or a computing cloud(s). In some implementations, each of the aforementioned may be generally described as a computing device. In certain implementations, a computing device may be a physical or virtual device. In many implementations, a computing device may be any device capable of performing operations, such as a dedicated processor, a portion of a processor, a virtual processor, a portion of a virtual processor, portion of a virtual device, or a virtual device. In some implementations, a processor may be a physical processor or a virtual processor. In some implementations, a virtual processor may correspond to one or more parts of one or more physical processors. In some implementations, the instructions/logic may be distributed and executed across one or more processors, virtual or physical, to execute the instructions/logic. Computer 12 may execute an operating system, for example, but not limited to, Microsoft® Windows®; Mac® OS X®; Red Hat® Linux®, or a custom operating system. (Microsoft and Windows are registered trademarks of Microsoft Corporation in the United States, other countries or both; Mac and OS X are registered trademarks of Apple Inc. in the United States, other countries or both; Red Hat is a registered trademark of Red Hat Corporation in the United States, other countries or both; and Linux is a registered trademark of Linus Torvalds in the United States, other countries or both).
[0036] In some implementations, the instruction sets and subroutines of system 100,
which may be stored on storage device, such as storage device 16, coupled to computer 12, may be executed by one or more processors (not shown) and one or more memory architectures included within computer 12. In some implementations, storage device 16 may include but is not limited to: a hard disk drive; a flash drive, a tape drive; an optical drive; a RAID array (or other array); a random access memory (RAM); and a read-only memory (ROM).
[0037] In some implementations, network 14 may be connected to one or more
secondary networks (e.g., network 18), examples of which may include but are not limited to: a local area network; a wide area network; or an intranet, for example.
[0038] In some implementations, computer 12 may include a data store, such as a
database (e.g., relational database, object-oriented database, triplestore database, etc.) and may be

located within any suitable memory location, such as storage device 16 coupled to computer 12. In some implementations, data, metadata, information, etc. described throughout the present disclosure may be stored in the data store. In some implementations, computer 12 may utilize any known database management system such as, but not limited to, DB2, in order to provide multi-user access to one or more databases, such as the above noted relational database. In some implementations, the data store may also be a custom database, such as, for example, a flat file database or an XML database. In some implementations, any other form(s) of a data storage structure and/or organization may also be used. In some implementations, system 100 may be a component of the data store, a standalone application that interfaces with the above noted data store and/or an applet / application that is accessed via client applications 22, 24, 26, 28. In some implementations, the above noted data store may be, in whole or in part, distributed in a cloud computing topology. In this way, computer 12 and storage device 16 may refer to multiple devices, which may also be distributed throughout the network.
[0039] In some implementations, computer 12 may execute application 20 for
management of a warehouse and specifically for managing pick-to-light (PTL) units in the warehouse. In some implementations, system 100 and/or application 20 may be accessed via one or more of client applications 22, 24, 26, 28. In some implementations, system 100 may be a standalone application, or may be an applet / application / script / extension that may interact with and/or be executed within application 20, a component of application 20, and/or one or more of client applications 22, 24, 26, 28. In some implementations, application 20 may be a standalone application, or may be an applet / application / script / extension that may interact with and/or be executed within system 100, a component of system 100, and/or one or more of client applications 22, 24, 26, 28. In some implementations, one or more of client applications 22, 24, 26, 28 may be a standalone application, or may be an applet / application / script / extension that may interact with and/or be executed within and/or be a component of system 100 and/or application 20. Examples of client applications 22, 24, 26, 28 may include, but are not limited to, a standard and/or mobile web browser, an email application (e.g., an email client application), a textual and/or a graphical user interface, a customized web browser, a plugin, an Application Programming Interface (API), or a custom application. The instruction sets and subroutines of client applications 22, 24, 26, 28, which may be stored on storage devices 30, 32, 34, 36, coupled to user devices 38, 40, 42, 44, may be executed by one or more processors and one or more memory architectures

incorporated into user devices 38, 40, 42, 44.
[0040] In some implementations, one or more of storage devices 30, 32, 34, 36, may
include but are not limited to: hard disk drives; flash drives, tape drives; optical drives; RAID arrays; random access memories (RAM); and read-only memories (ROM). Examples of user devices 38, 40, 42, 44 (and/or computer 12) may include, but are not limited to, a personal computer (e.g., user device 38), a laptop computer (e.g., user device 40), a smart/data-enabled, cellular phone (e.g., user device 42), a notebook computer (e.g., user device 44), a tablet (not shown), a server (not shown), a television (not shown), a smart television (not shown), a media (e.g., video, photo, etc.) capturing device (not shown), and a dedicated network device (not shown). User devices 38, 40, 42, 44 may each execute an operating system, examples of which may include but are not limited to, Android®, Apple® iOS®, Mac® OS X®; Red Hat® Linux®, or a custom operating system.
[0041] In some implementations, one or more of client applications 22, 24, 26, 28
may be configured to effectuate some or all of the functionality of system 100 (and vice versa). Accordingly, in some implementations, system 100 may be a purely server-side application, a purely client-side application, or a hybrid server-side / client-side application that is cooperatively executed by one or more of client applications 22, 24, 26, 28 and/or system 100.
[0042] In some implementations, one or more of client applications 22, 24, 26, 28
may be configured to effectuate some or all of the functionality of application 20 (and vice versa). Accordingly, in some implementations, application 20 may be a purely server-side application, a purely client-side application, or a hybrid server-side / client-side application that is cooperatively executed by one or more of client applications 22, 24, 26, 28 and/or application 20. As one or more of client applications 22, 24, 26, 28, system 100, and application 20, taken singly or in any combination, may effectuate some or all of the same functionality, any description of effectuating such functionality via one or more of client applications 22, 24, 26, 28, system 100, application 20, or combination thereof, and any described interaction(s) between one or more of client applications 22, 24, 26, 28, system 100, application 20, or combination thereof to effectuate such functionality, should be taken as an example only and not to limit the scope of the disclosure.
[0043] In some implementations, one or more of users 46, 48, 50, 52 may access
computer 12 and system 100 (e.g., using one or more of user devices 38, 40, 42, 44) directly

through network 14 or through secondary network 18. Further, computer 12 may be connected to network 14 through secondary network 18, as illustrated with phantom link line 54. System 100 may include one or more user interfaces, such as browsers and textual or graphical user interfaces, through which users 46, 48, 50, 52 may access system 100.
[0044] In some implementations, the various user devices may be directly or
indirectly coupled to network 14 (or network 18). For example, user device 38 is shown directly coupled to network 14 via a hardwired network connection. Further, user device 44 is shown directly coupled to network 18 via a hardwired network connection. User device 40 is shown wirelessly coupled to network 14 via wireless communication channel 56 established between user device 40 and wireless access point (i.e., WAP) 58, which is shown directly coupled to network 14. WAP 58 may be, for example, an IEEE 802.11a, 802.11b, 802.1 lg, Wi-Fi®, RFID, and/or Bluetooth™ (including Bluetooth™ Low Energy) device that is capable of establishing wireless communication channel 56 between user device 40 and WAP 58. User device 42 is shown wirelessly coupled to network 14 via wireless communication channel 60 established between user device 42 and cellular network / bridge 62, which is shown directly coupled to network 14.
[0045] In some implementations, some or all of the IEEE 802.1 lx specifications may
use Ethernet protocol and carrier sense multiple access with collision avoidance (i.e., CSMA/CA) for path sharing. The various 802. llx specifications may use phase-shift keying (i.e., PSK) modulation or complementary code keying (i.e., CCK) modulation, for example, Bluetooth™ (including Bluetooth™ Low Energy) is a telecommunications industry specification that allows, e.g., mobile phones, computers, smart phones, and other electronic devices to be interconnected using a short-range wireless connection. Other forms of interconnection (e.g., Near Field Communication (NFC)) may also be used.
[0046] The system 100 may include a computing system 200 (in the form of a server
device 200, as shown in FIG. 2) for warehouse management and help with management of PTL units therein by controlling data and power transmission therefor (as will be described later in more detail). Herein, FIG. 2 is a block diagram of an example of the server device 200 capable of implementing embodiments according to the present invention. In one embodiment, an application server as described herein may be implemented on exemplary server device 200. In the example of FIG. 2, the server device 200 includes a processing unit 205 (hereinafter, referred to as CPU

205) for running software applications (such as, the application 20 of FIG. 1) and optionally an operating system. Memory 210 stores applications and data for use by the CPU 205. Storage 215 provides non-volatile storage for applications and data and may include fixed disk drives, removable disk drives, flash memory devices, and CD-ROM, DVD-ROM or other optical storage devices. An optional user input device 220 includes devices that communicate user inputs from one or more users to the server device 200 and may include keyboards, mice, joysticks, touch screens, etc. A communication or network interface 225 is provided which allows the server device 200 to communicate with other computer systems via an electronic communications network, including wired and/or wireless communication and including an Intranet or the Internet. In one embodiment, the server device 200 receives instructions and user inputs from a remote computer through communication interface 225. Communication interface 225 can comprise a transmitter and receiver for communicating with remote devices. An optional display device 250 may be provided which can be any device capable of displaying visual information in response to a signal from the server device 200. The components of the server device 200, including the CPU 205, memory 210, data storage 215, user input devices 220, communication interface 225, and the display device 250, may be coupled via one or more data buses 260.
[0047] In the embodiment of FIG. 2, a graphics system 230 may be coupled with the
data bus 260 and the components of the server device 200. The graphics system 230 may include a physical graphics processing unit (GPU) 235 and graphics memory. The GPU 235 generates pixel data for output images from rendering commands. The physical GPU 235 can be configured as multiple virtual GPUs that may be used in parallel (concurrently) by a number of applications or processes executing in parallel. For example, mass scaling processes for rigid bodies or a variety of constraint solving processes may be run in parallel on the multiple virtual GPUs. Graphics memory may include a display memory 240 (e.g., a framebuffer) used for storing pixel data for each pixel of an output image. In another embodiment, the display memory 240 and/or additional memory 245 may be part of the memory 210 and may be shared with the CPU 205. Alternatively, the display memory 240 and/or additional memory 245 can be one or more separate memories provided for the exclusive use of the graphics system 230. In another embodiment, graphics processing system 230 includes one or more additional physical GPUs 255, similar to the GPU 235. Each additional GPU 255 may be adapted to operate in parallel with the GPU 235. Each additional GPU 255 generates pixel data for output images from rendering commands. Each

additional physical GPU 255 can be configured as multiple virtual GPUs that may be used in parallel (concurrently) by a number of applications or processes executing in parallel, e.g. processes that solve constraints. Each additional GPU 255 can operate in conjunction with the GPU 235, for example, to simultaneously generate pixel data for different portions of an output image, or to simultaneously generate pixel data for different output images. Each additional GPU 255 can be located on the same circuit board as the GPU 235, sharing a connection with the GPU 235 to the data bus 260, or each additional GPU 255 can be located on another circuit board separately coupled with the data bus 260. Each additional GPU 255 can also be integrated into the same module or chip package as the GPU 235. Each additional GPU 255 can have additional memory, similar to the display memory 240 and additional memory 245, or can share the memories 240 and 245 with the GPU 235. It is to be understood that the circuits and/or functionality of GPU as described herein could also be implemented in other types of processors, such as general-purpose or other special-purpose coprocessors, or within a CPU.
[0048] The system 100 may also include an end user or a client device 300 (as shown
in FIG. 3). In embodiments of the present disclosure, the client device 300 may embody an individual PTL unit. Herein, FIG. 3 is a block diagram of an example of the client device 300 capable of implementing embodiments according to the present invention. In the example of FIG. 3, the client device 300 includes a processing unit 305 (hereinafter, referred to as CPU 305) for running software applications (such as, the application 20 of FIG. 1) and optionally an operating system. A user input device 320 is provided which includes devices that communicate user inputs from one or more users and may include keyboards, mice, joysticks, touch screens, and/or microphones. Further, a communication interface 325 is provided which allows the client device 300 to communicate with other computer systems (e.g., the computing system 200 of FIG. 2) via an electronic communications network, including wired and/or wireless communication and including the Internet. The client device 300 may also include a decoder 355 may be any device capable of decoding (decompressing) data that may be encoded (compressed). A display device 350 may be provided which may be any device capable of displaying visual information, including information received from the decoder 355. In particular, as will be described below, the display device 350 may be used to display visual information received from the server device 200 of FIG. 2. The components of the client device 300 may be coupled via one or more data buses 360.
[0049] It may be seen that compared to the server device 200 in the example of FIG.

2, the client device 300 in the example of FIG. 3 may have fewer components and less functionality and, as such, may be referred to as a user device or the like. However, the client device 300 may include other components including those described above. In general, the client device 300 may be any type of device that has display capability, the capability to decode (decompress) data, and the capability to receive inputs from a user and send such inputs to the computing system 200. However, the client device 300 may have additional capabilities beyond those just mentioned.
[0050] Referring now to FIG. 4, illustrated is an exemplary rack 400 that may be
employed in a warehouse. In the illustration of FIG. 4 only a portion of the rack 400 is shown to illustrate details of various components arranged therewith. It may be contemplated by a person skilled in the art that a typical warehouse includes a plurality of racks (such as, the racks 400, also sometimes referred to as picking bays) that are arranged in spaced apart rows which define therebetween a picking aisle, and each such picking aisle generally providing access to two opposing racks. Though reference hereinafter is made to two rows of racks and one aisle, it can be appreciated that a plurality of rows and aisles are contemplated in a warehouse. The picking aisle preferably provides sufficient open space for operators to move between the racks 400 so that the operators are not limited to a specific zone or specific set of racks.
[0051] The rack 400 comprises a conventional case flow bay or rack, which includes
a frame 402 and a plurality of vertically spaced shelves 404 that are supported by the frame 402. In some examples, each of the shelves 404 may include a plurality of rollers (not shown). In such case, each shelf 404 is typically canted or tilted so that products placed on the rollers forming the shelf 404 will flow to one side thereof. The lower side of the shelves 404 are typically aligned along a discharge side of the bay, while the higher side of the shelves are aligned along an induct side of the bay. Products are delivered by pallets and are placed on the shelves 404 in the rack 400. The products are typically delivered in boxes, which are then opened by an operator and placed on the shelf 404 from the induct side thereof.
[0052] In some examples, along vertical sides of the frame 402, vertical lifts (not
shown) are arranged by way of example in any number and are movable in the vertical direction in order to be able to reach different levels of the shelves 404. The lifts in particular have load-receiving means, by means of which storage containers or other loading aids, such as trays, move in the horizontal direction between the shelves 404 and the lifts, and thus can be exchanged. The

lift thus retrieves storage containers from the shelves 404 and provides them, preferably at its lower end, for further processing, for instance to be picked-up by an operator. In some examples, order containers are transported to picking stations via a central conveyor.
[0053] Further, as may be seen, the shelves 404 are virtually divided into several
sections, with each such section acting as a storage area or storage rack 406. In the example illustration of FIG. 4, each shelf 404 is shown to have four storage racks 406. It may be appreciated that a given shelf 404 may have more or less number of storage racks 406 without departing from the scope and spirit of the present disclosure. Each storage rack 406 is here uniquely associated with one of the put areas. Generally, each of the put areas is partially or fully filled with a particular item, generally in loose form; however, the storage rack 406 can also be filled with containers, without any limitations.
[0054] Further, as illustrated, each of the storage racks 406 is associated with a pick-
to-light (PTL) unit 408. Such devices are also sometimes referred to as Put-to-light (PTL) units in the art. Herein, the PTL unit 408 forms part of the system 100, which is a signalling system, for warehouse management. In the illustrated example of the rack 400, the PTL units 408 corresponding to the storage racks 406 in the lowermost shelf 404 may be arranged on the shelf 404 immediately above thereof to provide convenient accessibility to the operator for configuring the corresponding PTL units 408. In some examples, the PTL units 408 corresponding to the storage racks 406 in the lowermost shelf 404 may be differently coloured as compared to the other PTL units to avoid confusion with the PTL units 408 corresponding to the storage racks 406 in the immediate above shelf 404 to the lowermost shelf 404.
[0055] Typically, a warehouse is divided into multiple zones, depending on various
factors such as affinity of products placed therein, coverage area of an operator, or the like. In the present example, a given rack, such as the rack 400, may be considered as a single zone for purposes of explanation of embodiments of the present disclosure; although it may be noted that typically a single zone has multiple racks therein. Hereinafter, the terms "rack" and "zone" have been interchangeably used without any limitations.
[0056] According to embodiments of the present disclosure, the system 100 catering
to the zone 400 includes a plurality of PTL units 408. As shown in the illustration of FIG. 4, each of the plurality of PTL units 408 is connected to a bus connection 410. It would be understood the

warehouse may include a number of such bus connections, with each such bus connection serving a plurality of PTL units 408 in a single zone. In the present embodiments, the plurality of PTL units 408 are connected in series to the bus connection 410, as shown in FIG. 4. As used herein, the bus connection 410 refers to one of the sets of conductors (e.g., wires, and printed traces or connections) connecting two or more functional units. The data bus, power bus, address bus and control bus, despite their names, constitute a single bus since each are often useless without the others. In the present examples, the term "bus connection" covers all possible connections for the exchange of data and power for PTL units 408.
[0057] As illustrated, the system 100 also includes a server 411 (similar in
configuration to the server 200). The server 411 may be any computer or hardware on which the services that clients use reside. Services available on the server are transmitted from the server software to the client software over communication lines in packets of data according to defined protocols. Generally, the term "server" means a discrete host computer in a network, and it provides services to other computers or devices, termed "clients". For purposes of the example embodiments described herein, the term "server" includes machines that can be essentially any interconnected computer systems. The use of terms such as "server" is not meant to imply that any particular machine can only be performing host function, or that any particular machine cannot be acting as a client computing platform in any particular circumstance. The server 411 is configured to receive data packets from the plurality of PTL units 408. In present embodiments, the server 411 is further configured to send data packets to the plurality of PTL units 408 via the controller (as will be discussed in the proceeding paragraphs). Herein, the server 411 may be part of a larger warehouse management system (WMS) as known in the art.
[0058] Further, the system 100 includes a controller 412. Herein, the controller 412
may be any processing device, system or part thereof that controls at least one operation of the device. The controller 412 may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. The controller 412 may be a multi-core processor, a single core processor, or a combination of one or more multi-core processors and one or more single core processors. For example, the one or more processors may be embodied as one or more of various processing devices, such as a coprocessor, a microprocessor, a controller, a digital signal processor (DSP), a processing circuitry with or

without an accompanying DSP, or various other processing devices including integrated circuits such as, for example, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a microcontroller unit (MCU), a hardware accelerator, a special-purpose computer chip, or the like. Further, the memory may include one or more non-transitory computer-readable storage media that can be read or accessed by other components in the device. The memory may be any computer-readable storage media, including volatile and/or non-volatile storage components, such as optical, magnetic, organic or other memory or disc storage, which can be integrated in whole or in part with the device. In some examples, the memory may be implemented using a single physical device (e.g., optical, magnetic, organic or other memory or disc storage unit), while in other embodiments, the memory may be implemented using two or more physical devices without any limitations.
[0059] As illustrated in FIG. 4, the controller 412 is disposed in signal
communication with the server 411. In the present embodiments, the controller 412 may be disposed in signal communication with the server 411 via an Ethernet-based local area network via a line 413. It may be appreciated that the said Ethernet-based local area network may utilize TCP/IP protocol for communication and transmission of data packets. The controller 412 is further in signal communication with the plurality of PTL units 408 via the bus connection 410. Further, herein, the system 100 implements power line communication over the bus connection 410. In the present embodiments, as illustrated in FIG. 4, the system 100 may include a single or common controller 412 which may be connected to each of the said plurality of PTL units 408 via the bus connection 410. Further, each of the plurality of PTL units 408 may include a corresponding individual controller (not shown in FIG. 4) which may be connected to the individual controllers in other of the PTL units 408 via the bus connection 410.
[0060] It may be appreciated that in the embodiment, as illustrated in FIG. 4, the
controller 412 may still be provided to receive commands related to normal functioning of the PTL units 408, as will be explained later in the description. The said individual controller in each of the PTL units 408 may issue or broadcast commands to the other individual controllers in other of the PTL units 408 in the plurality of PTL units 408 via the bus connection 410. Such individual controllers may be able to receive data packets (e.g. commands from the server 411) for the corresponding PTL unit 408 in the plurality of PTL units 408 and/or send data packets (e.g. confirmation message) to the server 411, via the controller 412 (as will be discussed later in more

detail).
[0061] As discussed, the server 411 is connected to the controller 412 via the
Ethernet-based local area network, and such Ethernet-based local area network may implement TCP/IP protocol as known in the art. The system 100 implements power line communication with differential signal over the bus connection 410 for communication, which may be based on RS-485 serial communication protocol. Such standard provides balanced electrical signalling and support polarity-free multipoint systems. Digital communications networks implementing such standard can be used effectively over long distances and in electrically noisy environments, thus making it suitable for industrial control systems and similar applications, including present warehouse management applications. As may be understood that the server 411 may implement TCP IP protocol and the PTL units 408 may implement a power line communication protocol; so, in the present embodiments, the controller 412 acts as a gateway or a part of a gateway (such as, an Ethernet-RS-485 gateway) to facilitate proper communication between the server 411 and the plurality of PTL units 408.
[0062] Referring now to FIG. 5, illustrated is a detailed circuit diagram of a system
500 for managing the plurality of PTL units 408 in the warehouse, in accordance with one or more exemplary embodiments of the present disclosure. In particular, FIG. 5 provides a circuit view of a power line communication arrangement 502 in the system 500. As discussed, the system 500 includes the controller 412 in signal communication with a server (such as the server 411, not shown herein) to receive data packets to be transmitted to the plurality of PTL units 408. Herein, for the purposes of explanation only one PTL unit 408 has been shown, but it may be contemplated that the embodiments described herein may be implemented for other PTL units of the plurality of PTL units 408 without any limitations. The system 500 further includes a power supply 501 configured to provide DC power for operation of each of the plurality of PTL units 408. Such power supply 501 may be contemplated by a person skilled in the art and thus has not been described herein for the brevity of the present disclosure.
[0063] Herein, the power line communication arrangement 502 includes the bus
connection 410. According to embodiments of the present disclosure, the bus connection 410 includes two wires 410a, 410b. Each of the two wires 410a, 410b (also sometimes referred to as "signal lines 410a, 410b) in the bus connection 410 is implemented for both data and power

transmission in the system 500. Each of the two wires 410a, 410b has two or more connection points, that form a main transmission path that electrically connects the plurality of PTL units 408 to the controller 412. A signal line refers to one or more electrical conductors or optical carriers, generally configured as a single carrier or as two or more carriers, in a twisted, parallel, or concentric arrangement, used to transport at least one logical signal. In preferred examples, the bus connection 410 has parallel wires therein. Herein, the bus connection 410 may be a point-to-point connection. As used herein, the term "point-to-point" bus and/or link refers to one or a plurality of signal lines that may each include one or more terminators. In a point-to-point bus and/or link, each signal line has two transceiver connection points, with each transceiver connection point coupled to transmitter circuitry, receiver circuitry or transceiver circuitry.
[0064] In an embodiment of the present disclosure, the bus connection 410 may
provide a tapped connection to the plurality of PTL units 408 from the controller 412, such that the various PTL units of the plurality of PTL units 408 are arranged parallel to each other with respect to the controller 412, so as to independently receive signals therefrom and send signal thereto. That is, for example, the controller 412 may be node 1, and the PTL units 408 may be node 2, node 3, ..., node n; in such case, the node 2, node 3, ..., node n may be connected to the bus connection 410 by tapping to be disposed in a parallel circuit configuration to receive the signals directly from the controller 412.
[0065] Further, as illustrated, the power line communication arrangement 502
includes a first transceiver 504. The first transceiver 504 is associated with the controller 412 to receive the data packets therefrom. By association of the first transceiver 504 with the controller 412, it is meant that in some examples, the first transceiver 504 may be integrated with the controller 412, i.e. the functionality of the first transceiver 504 may be programmed in the controller 412 itself; or in other examples, the first transceiver 504 may be a separate transceiver or the like which may be connected to the controller 412. The first transceiver 504 is further coupled to the bus connection 410. For this purpose, the terminals of the first transceiver 504 are connected to the two wires 410a, 410b of the bus connection 410. Such first transceiver 504 may provide a pin programmable interface which allows for such connection and thus simplifies the circuit design.
[0066] The power line communication arrangement 502 also includes a second

transceiver 506. The second transceiver 506 is associated with one of the plurality of PTL units 408 (as shown in FIG. 5). Again by association of the second transceiver 506 with the PTL unit 408, it is meant that in some examples, the second transceiver 506 may be integrated with the individual controller (as discussed) of the corresponding PTL unit 408, i.e. the functionality of the second transceiver 506 may be programmed in the said individual controller of the corresponding PTL unit 408 itself; or in other examples, the second transceiver 506 may be a separate transceiver or the like which may be connected to the corresponding PTL unit 408. The second transceiver 506 is also further coupled to the bus connection 410. For this purpose, the terminals of the second transceiver 506 are connected to the two wires 410a, 410b of the bus connection 410. The second transceiver 506 may also provide a pin programmable interface which allows for such connection and thus simplifies the circuit design.
[0067] The power line communication arrangement 502 also includes a first series
capacitances 508. The first series capacitances 508 is associated with the controller 412. That is, the first series capacitances 508 may be arranged to control the signals from the controller 412, in the power line communication arrangement 502. The first series capacitances 508 is also coupled to the bus connection 410. As shown, the first series capacitances 508 may be in the form of two capacitors CI, C2, with the two capacitors CI, C2 being arranged in parallel on the two wires 410a, 410b of the bus connection 410. The power line communication arrangement 502 further includes a second series capacitances 510. The second series capacitances 510 is associated with the said one of the plurality of PTL units 408. That is, the second series capacitances 510 may be arranged to control the signals transmitted to the PTL unit 408, in the power line communication arrangement 502. The second series capacitances 510 is also coupled to the bus connection 410. As shown, the second series capacitances 510 may be in the form of two capacitors C3, C4, with the two capacitors C3, C4 being arranged in parallel on the two wires 410a, 410b of the bus connection 410.
[0068] The power line communication arrangement 502 further includes a first series
inductances 512. The first series inductances 512 is associated with the controller 412. The first series inductances 512 is also coupled to the bus connection 410. As shown, the first series inductances 512 may be in the form of two inductors LI, L2, with the two inductors LI, L2 being arranged in parallel with the two wires 410a, 410b of the bus connection 410. The first series inductances 512 disposes the power supply 501 in electrical connection with the bus connection

410 for transmission of DC power therefrom. The power line communication arrangement 502 also includes a second series inductances 514. The second series inductances 514 is associated with the said one of the plurality of PTL units 408. The second series inductances 514 is also coupled to the bus connection 410. As shown, the second series inductances 514 may be in the form of two inductors L3, L4, with the two inductors L3, L4 being arranged in parallel with the two wires 410a, 410b of the bus connection 410. The second series inductances 514 disposes the power supply 501 in electrical connection with the PTL unit 408 for transmission of DC power thereto.
[0069] According to embodiments of the present disclosure, in the power line
communication arrangement 502, the first transceiver 504 is configured to modulate the received data packets, from the controller 412 (as may be received from the server 411, whether processed or unprocessed by the controller 412). Herein, the first transceiver 504 modulates the received data packets with a carrier signal to generate a high frequency clock signal. Further, the first series capacitances 508 is configured to couple the high frequency clock signal from the first transceiver 504 to the bus connection 410. Such a generated high frequency clock signal is transmitted over the two wires 410a, 410b in the bus connection 410. As used herein, the term "clock signal" refers to a particular type of signal that oscillates between a high and a low state. The clock signal acts like a metronome, which the digital circuit follows in time to coordinate its sequence of actions. This way, the PTL units 408 may rely on clock signals to know when and how to execute the functions that are programmed. Further, in the power line communication arrangement 502, the first series inductances 512 is configured to couple the DC power from the power supply 501 to be transmitted over the two wires 410a, 410b in the bus connection 410. The role of capacitors CI, C2 in the first series capacitances 508 and the inductors LI, L2 in the first series inductances 512 for the given purposes may be contemplated by a person skilled in the art of circuit design, still some details have been provided later in the description as specific examples which shall not be construed as limiting to the present disclosure in any manner.
[0070] Further, according to embodiments of the present disclosure, at other end in
the power line communication arrangement 502, the second transceiver 506 is configured to demodulate the high frequency clock signal, as received over the bus connection 410, to extract the data packets therefrom. The data packets are extracted so as to be processed by the said one of the plurality of PTL units 408. The data packets may provide necessary information for actions on

part of the PTL unit 408 in the operations of the warehouse. Herein, the second series capacitances 510 is configured to decouple the high frequency clock signal from the bus connection 410 to be utilized by the said one of the plurality of PTL units 408. That is, the second series capacitances 510 helps with decoupling the high frequency clock signal from the bus connection 410. Further, in the power line communication arrangement 502, the second series inductances 514 is configured to decouple the DC power from the bus connection 410 to be supplied to a load (as represented by label 'X' in FIG. 5) of the said one of the plurality of PTL units 408. The role of capacitors C3, C4 in the second series capacitances 510 and the inductors L3, L4 in the second series inductances 514 for the given purposes may be contemplated by a person skilled in the art of circuit design, still some details have been provided later in the description as specific examples which shall not be construed as limiting to the present disclosure in any manner.
[0071] In one or more embodiments, the first transceiver 504 and the second
transceiver 506 implement On-off keying (OOK) modulation scheme. Herein, On-off keying (OOK) denotes the simplest form of amplitude-shift keying (ASK) modulation that represents digital data as the presence or absence of a carrier signal. In its simplest form, the presence of a carrier for a specific duration represents a binary one, while its absence for the same duration represents a binary zero. Some more sophisticated schemes vary these durations to convey additional information. In the system design, the frequency of the carrier signal of the OOK modulation is selected based on the desired data rate and the expected AC losses through the bus connection 410. In the present embodiments, the carrier signal has a frequency at least ten times higher than a frequency of the received data packets. That is, it is warranted that the carrier frequency is at least 10 times faster than the data rate; or in other words, there are more than 10 cycles in one-bit period of the data. For example, for 19200 baud rate application, the carrier frequency of 300 kHz can be used. For 115200 baud, a carrier frequency of at least -1.2 MHz is preferred. This helps to minimize bit timing distortion due to asymmetries in rising and falling signal transitions that can occur during modulation and demodulation.
[0072] In the present system 500, the parallel cabling for the two wires 410a, 410b
in the bus connection 410 is preferred to allow the PTL units 408 to form tapped connected therewith. Also, the bus connection 410 should have enough current rating and low enough series resistance for delivering power without excessive voltage drop. Further, the coupled common mode noise could be presented differentially on the bus connection 410. Therefore, additional

means may be provided for minimizing the noise coupling in the system 500. Furthermore, with proper termination that matches cable's characteristic impedance, the bus reflections are minimized to provide the best signal integrity. Nevertheless, other topologies could possibly be implemented depending on the data rate and distance. Similarly, use of length-matched cabling is important to be considered when transmitting higher-speed differential signals. Length mismatches would lead to phase imbalance between the inverting and non-inverting lines, and this would result in a portion of the differential signalling to common mode. The mode conversion could result in higher EMI, and in more severe cases could result in a loss of communication. Further, the inductors L1-L4 and capacitors C1-C4 value selection may be based on the impedance at the carrier frequency of OOK modulation. A rule of thumb is that the total inductor impedance should remain larger than 375 Q, and each capacitor's impedance is less than 5 Q. The reasoning behind this stems from the RS-485 standard, where a minimum 1.5 V differential voltage is required from each output driver when considering a 54-Q load.
[0073] As discussed, the first transceiver 504 modulates the received data packets
with the carrier signal. With such transceivers, a frequency of the carrier signal can be adjusted by changing an external resistor on the FSET pin of the first transceiver 504 and the second transceiver 506. A broad range of carrier frequencies gives the system designer the flexibility to choose the external inductors and capacitors. Herein, Data at a D input is modulated with the carrier frequency (fO) when OOK modulation mode is set via FSET. A high level at the D input is driven to the mid-level with zero differential voltage (VOD) and a low level at the D input is modulated at the carrier frequency. As discussed, it is recommended to use a carrier frequency that is lOx higher than the data rate. Higher data rates are possible at the expense of increased pulse width distortion with the use of lower ratios. Therefore, the input Transistor-Transistor Logic (TTL) data from the controller 412 (i.e. microcontroller (MCU)) is OOK modulated by the first transceiver 504 onto the bus connection 410, in which the input low is converted to a high frequency clock signal, while the input high stays as a DC voltage.
[0074] Built-in on-off keying (OOK) modulation in the first transceiver 504 and the
second transceiver 506 enables input TTL data to be directly coupled onto shared wires 410a, 410b of the bus connection 410 via the first series capacitances 508 without requiring any updates to the controller 412. Also, as may be understood, the power on the bus connection 410 is decoupled by the second series inductances 514 that show high impedance at the frequency of OOK data. Herein,

the second series capacitances 510 extracts the data from the two wires 410a, 410b of the bus connection 410 after AC-coupling by utilizing a precise bandpass filter. The OOK signal received at the inputs at the other end go through a bandpass filter and a peak detector to regenerate the original data stream when the device is in OOK mode. The bandpass filter characteristics will adapt to optimal settings automatically based on the carrier frequency. In accordance with one or more embodiments, the bus connection 410 includes a diode bridge (not shown) to supply a same polarity of the DC power to the load of the said one of the plurality of PTL units as the received DC power therein.
[0075] The present system 500 enables power line communication. Built-in on-off
keying (OOK) modulation enables input Transistor-Transistor Logic (TTL) data to be directly coupled onto shared power cables via series capacitors without any updates to the microcontroller (MCU). Only two-wire cable is required to transmit both power supply and data signals. To be more specific, OOK modulation converts a logic-low input to a high frequency clock signal, while a logic-high input results in a DC voltage. The receiver in the system 500 extracts the data from the power cables after AC-coupling by utilizing a precise bandpass filter and a demodulator. The power on the bus is decoupled by series inductors that show high impedance at the frequency of OOK data. Since the system 500 leverages power line communication using differential signalling, it inherits some RS-485 features like balanced multipoint transmission and common mode noise immunity. Also same as RS-485 transceivers, the transceivers 504, 506 are physical-layer-only devices. This makes the system 500 simple to implement and flexible in various applications requiring different higher-layer data communication protocols. The system 500 works with universal asynchronous receiver-transmitter (UART) signalling from MCU and can directly replace the existing RS-485 signal link.
[0076] Although herein, as above, the system 500 has been described in terms of the
first transceiver 504 associated with the controller 412 to modulate the signal and then the second transceiver 506 associated with the PTL unit 408 to demodulate the signal, which is the case when there is need of sending data from the controller 412 to the PTL unit 408; it may be appreciated that when there is need of sending data from the PTL unit 408 to the controller 412 (say, when the PTL unit 408 needs to send confirmation as provided by a picker), in such case, the second transceiver 506 associated with the PTL unit 408 modulates the signal and then the first transceiver 504 associated with the controller 412 demodulates the signal, and the signal from the controller

412 may be sent to the server (e.g. server 411) for further processing.
[0077] The present disclosure further provides a method for managing a plurality of
PTL units in the warehouse. Various embodiments and variants disclosed above, with respect to the aforementioned system, apply mutatis mutandis to the present method for managing a plurality of PTL units in the warehouse.
[0078] FIG. 6 illustrates a flowchart 600 listing steps involved in the said method for
managing a plurality of PTL units in a warehouse. At step 602, the method includes receiving, by a controller, data packets from a server to be transmitted to the plurality of PTL units. At step 604, the method includes providing a bus connection comprising two wires, to couple a first transceiver and a first series inductances associated with the controller, and a second transceiver and a second series inductances associated with one of the plurality of PTL units. At step 606, the method includes modulating, by the first transceiver, the received data packets with a carrier signal to generate a high frequency clock signal. At step 608, the method includes coupling, by the first series inductances, DC power from a power supply to be transmitted over the two wires in the bus connection. At step 610, the method includes demodulating, by the second transceiver, the high frequency clock signal to extract the data packets therefrom to be processed by the said one of the plurality of PTL units. At step 612, the method includes decoupling, by the second series inductances, the DC power from the bus connection to be supplied to a load of the said one of the plurality of PTL units.
[0079] In one or more embodiments, the bus connection further couples a first series
capacitances associated with the controller and a second series capacitances associated with the said one of the plurality of PTL units. Herein, the method further comprises coupling, by the first series capacitances, the high frequency clock signal from the first transceiver to the bus connection; and decoupling, by the second series capacitances, the high frequency clock signal from the bus connection to be transmitted to the said one of the plurality of PTL units. In one or more embodiments, the method further comprises implementing the carrier signal having a frequency at least ten times higher than a frequency of the received data packets. In one or more embodiments, the method further comprises configuring the first transceiver and the second transceiver to implement On-off keying (OOK) modulation scheme.
[0080] The systems and the methods of the present disclosure allows for transmitting

both the data (data transmission) and the DC power (power transmission) over the bus connection 410 with only two wires 410a, 410b; as compared to the conventional system which require at least four wires for such purposes. Herein, the data packets (data signal) are carried with the DC power on the same two wires 410a, 410b of the bus connection 410. In particular, at the transmitter side, the first transceiver 504 modulates the received data packets with a carrier signal to be carried with the DC power as coupled by the first series inductances 512. Specifically, herein, high-frequency differential data is AC-coupled onto the bus connection 410 via the first series capacitances 508 while the DC power is DC-coupled via the first series inductances 512. Similarly, at the receiver side, the second transceiver 506 demodulates the differential signal to digital domain while the DC power is decoupled to be extracted/separated by the second series inductances 514 to drive the load of the PTL unit 408. Specifically, herein, AC-coupled data is extracted from the bus connection 410 via the second series capacitances 510 by isolating the low frequency bus voltage while the DC power is decoupled via the second series inductances 514. In general, the second series capacitance 510 allows the DC power to flow on the bus connection based on ratings of the capacitors C1-C4, and the inductors L1-L4 does not allow the signal to pass through so the DC power is protected, and thus it is possible for the data and power to be transmitted and extracted by the respective nodes and communication takes place. This ultimately helps to reduce the number of wires in the bus connection 410 (i.e. only two wires 410a, 410b are required) while increasing system performance and lowering overall cost.
[0081] The foregoing descriptions of specific embodiments of the present disclosure
have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiment was chosen and described in order to best explain the principles of the present disclosure and its practical application, to thereby enable others skilled in the art to best utilize the present disclosure and various embodiments with various modifications as are suited to the particular use contemplated.

WE CLAIM:

1. A system for managing a plurality of pick-to-light (PTL) units in a warehouse, the system
comprising:
a controller in signal communication with a server to receive data packets to be transmitted to the plurality of PTL units;
a power supply configured to provide DC power for operation of each of the plurality of PTL units;
a power line communication arrangement comprising:
a bus connection comprising two wires;
a first transceiver associated with the controller to receive the data packets therefrom and coupled to the bus connection, the first transceiver configured to modulate the received data packets with a carrier signal to generate a high frequency clock signal to be transmitted over the two wires in the bus connection;
a first series inductances associated with the controller and coupled to the bus connection, the first series inductances configured to couple the DC power from the power supply to be transmitted over the two wires in the bus connection;
a second transceiver associated with one of the plurality of PTL units and coupled to the bus connection, the second transceiver configured to demodulate the high frequency clock signal to extract the data packets therefrom to be processed by the said one of the plurality of PTL units; and
a second series inductances associated with the said one of the plurality of PTL units and coupled to the bus connection, the second series inductances configured to decouple the DC power from the bus connection to be supplied to a load of the said one of the plurality of PTL units.
2. The system as claimed in claim 1, wherein the power line communication arrangement further
comprises a first series capacitances associated with the controller and coupled to the bus
connection, the first series capacitances configured to couple the high frequency clock signal
from the first transceiver to the bus connection.

3. The system as claimed in claim 2, wherein the power line communication arrangement further comprises a second series capacitances associated with the said one of the plurality of PTL units and coupled to the bus connection, the second series capacitances configured to decouple the high frequency clock signal from the bus connection to be utilized by the said one of the plurality of PTL units.
4. The system as claimed in claim 1, wherein the carrier signal has a frequency at least ten times higher than a frequency of the received data packets.
5. The system as claimed in claim 1, wherein the first transceiver and the second transceiver implement On-off keying (OOK) modulation scheme.
6. The system as claimed in claim 1, wherein the bus connection comprises a diode bridge to supply a same polarity of the DC power to the load of the said one of the plurality of PTL units as the received DC power therein.
7. A method for managing a plurality of pick-to-light (PTL) units in a warehouse, the method
comprising:
receiving, by a controller, data packets from a server to be transmitted to the plurality of PTL units;
providing a bus connection comprising two wires, to couple a first transceiver and a first series inductances associated with the controller, and a second transceiver and a second series inductances associated with one of the plurality of PTL units;
modulating, by the first transceiver, the received data packets with a carrier signal to generate a high frequency clock signal;
coupling, by the first series inductances, DC power from a power supply to be transmitted over the two wires in the bus connection;
demodulating, by the second transceiver, the high frequency clock signal to extract the data packets therefrom to be processed by the said one of the plurality of PTL units; and
decoupling, by the second series inductances, the DC power from the bus connection to be supplied to a load of the said one of the plurality of PTL units.

8. The method as claimed in claim 7, wherein the bus connection further couples a first series
capacitances associated with the controller and a second series capacitances associated with
the said one of the plurality of PTL units, and wherein the method further comprises:
coupling, by the first series capacitances, the high frequency clock signal from the first transceiver to the bus connection; and
decoupling, by the second series capacitances, the high frequency clock signal from the bus connection to be transmitted to the said one of the plurality of PTL units.
9. The method as claimed in claim 7 further comprising implementing the carrier signal having a frequency at least ten times higher than a frequency of the received data packets.
10. The method as claimed in claim 7 further comprising configuring the first transceiver and the second transceiver to implement On-off keying (OOK) modulation scheme.