Excitation source system and first device for managing backscatter interference

Abstract

The present disclosure relates to an excitation source system configured to transmit a first signal to a first device (e.g., a reader device) and a second signal to a second device (e.g., a backscatter device containing data to be collected by the reader device). The second signal is configured to excite the second device to generate a backscattered signal receivable by the first device. The source excitation system is configured to receive a feedback signal from the first device. The feedback signal may enable the excitation source system to determine feedback information based on the first excitation signal and the backscatter signal received at the first device. The excitation source system may be further configured to determine one or more adjustment parameters based on the feedback information to obtain an adjusted first signal. The adjusted first signal may enable management of reception quality of another backscatter signal triggered by another second signal from the excitation source system at the first device.

Description

Technical Field

[0001] The present disclosure relates to an excitation source system and a first device (eg, a backscatter reading device) for managing the reception quality of a backscatter signal from a second device. In particular, the present disclosure relates to managing interference of the backscatter signal at the first device. Background Art

[0002] Low-power networks are a key component of the Internet of Things (IoT) and Machine-to-Machine (M2M) communications. For example, low-power devices may rely on energy harvesting, which requires that these devices must operate in an energy-efficient manner. Such devices can be referred to as power-constrained devices.

[0003] For example, 3GPP recently published a study on ambient power-enabled IoT devices in the technical recommendation 3GPP TR 22.840. The document discloses the use cases and requirements of ambient power IoT devices, which are battery-free and have limited energy storage capabilities (possibly including a capacitor), where energy is provided, for example, by harvesting radio waves. Such ambient power IoT devices are preferably of low complexity.

[0004] Backscatter communication is one of the core technologies to achieve zero-power communication. Backscatter communication may involve a source device generating a signal, powering a backscatter device, and triggering a backscatter signal from the device. The backscatter signal may be modulated so as to carry data in the backscatter signal, which may be received by a local reader device that is the destination or hub of the data.

[0005] One of the challenges faced by such communication systems is that the backscatter signal is not easily received by the reader device. The difficulty in receiving the backscatter signal is due to the two-way attenuation of the backscatter signal reducing the signal strength at the reader device, and the strong direct link between the source device and the reader device drowning out the weaker backscatter signal. To address the latter problem, it has been proposed to have the backscatter device frequency modulate the backscatter signal, but this increases the complexity required of the backscatter device. Summary of the invention

[0006] In order to improve the reception of backscatter signals at the reader device, the inventors have recognized that the above-mentioned conditions in the backscatter communication can be exploited to facilitate the reception of the backscatter signals. In particular, the inventors aim to enhance the reception of the backscatter signals by adapting the source signal from the source device, so that no or only a small amount of backscatter device adaptation is required.

[0007] One aspect of the present disclosure relates to an excitation source system, which is configured to transmit a first signal to a first device (e.g., a reader device) and transmit a second signal to a second device (e.g., a backscatter device containing data to be collected by the reader device). The second signal is configured to excite the second device to generate a backscatter signal that can be received by the first device. The source excitation system is configured to receive a feedback signal from the first device. The feedback signal can enable the excitation source system to determine feedback information based on the first excitation signal and the backscatter signal received at the first device. The excitation source system can be further configured to determine one or more adjustment parameters based on the feedback information to obtain an adjusted first signal. The adjusted first signal can enable management of the reception quality of another backscatter signal at the first device that is triggered by another second signal from the excitation source system.

[0008] Another aspect of the disclosure relates to a first device, e.g., a reader device, configured to read data from a second device (e.g., a backscatter device) via backscatter communication, wherein the backscatter communication is triggered by an external excitation source system. The first device is configured to receive a first signal from the excitation source system and receive a backscatter signal from the second device. The first device may be further configured to transmit a feedback signal to the excitation source system, the feedback signal enabling the excitation source system to determine feedback information based on the first excitation signal and the backscatter signal.

[0009] Where previously it was believed that a first signal from an excitation source system was detrimental to receiving a backscattered signal at a reader, this document discloses using the first signal, i.e., determining, if necessary, to adjust the first signal in an initialization phase based on feedback regarding the reception of the first signal and the backscattered signal at the reader device. By managing the reception quality at the reader device, data reception during a data acquisition phase can be controlled when transmitting the adjusted first signal and another second signal.

[0010] The initialization phase (ie, the phase of obtaining adjustment parameters) may be repeated several times, for example, alternating with the data obtaining phase or under the control of a management system.

[0011] It should be understood that the feedback information may include measurement data or processed measurement data about the first signal and the backscattered signal. For example, the feedback signal may include raw measurement data, such as signal strength, signal phase, etc. of each signal, and may also include processed signal data, such as signal strength difference, phase difference, etc. The nature of the feedback signal depends on, for example, the capacity of the excitation source system and the first device. In some embodiments, the feedback information may include one or more of the adjustment parameters derived at the first device, which may be applied by the excitation source system when received in the feedback signal.

[0012] It should also be understood that Gu et al. have previously described the use of interferometry in a backscatter communication system using tag selection in IEEE Transaction on Communications, Vol. 71, pp. 4344-4359. The present disclosure operates independently of tag location by enabling adjustment of a characteristic of the first signal, such as phase and / or amplitude, to optimize reception of the backscatter signal at the first device.

[0013] In one embodiment, the feedback information obtained at the excitation source system can be related to the phase difference between the first signal and the backscattered signal at the reader device. The adjustment parameter derived from the feedback information can be related to the phase shift of the first signal to obtain constructive interference between the adjusted first signal and another backscattered signal at the first device.

[0014] In one embodiment, the feedback information provided by the first device is related to a phase of the first signal and the backscattered signal, a phase difference between the first signal and the backscattered signal, and / or a phase shift of the first signal.

[0015] By informing the excitation source system of the first signal of the phase required to obtain constructive interference of the phase-adjusted first signal and the further backscattered signal, the reception quality at the first device may be enhanced.

[0016] In one embodiment, the feedback information obtained at the excitation source system may be further related to at least one of a signal-to-noise ratio (SNR) of the backscattered signal and an error estimate of the backscattered signal.

[0017] In one embodiment, the feedback information provided by the first device may further be related to at least one of a signal-to-noise ratio SNR of the backscattered signal and an error estimate of the backscattered signal.

[0018] Both the SNR and the error estimate can be used to manage the reception quality of the backscattered signal at the first device. For example, if the SNR is low, the first signal can be phase and amplitude adjusted to enhance the reception quality. If the error estimate indicates that the reception quality was already good during the initialization phase, the first signal can be adjusted slightly or even not at all.

[0019] In one embodiment, the excitation source system can be configured so that the first signal includes a predetermined data sequence, and the second signal also includes the predetermined data sequence or an indication, which is configured to trigger the second device to include the predetermined data sequence in the backscattered signal. In the latter case, the second device can pre-store the predetermined data sequence. The indication can also indicate that the second device does not include the predetermined data sequence. The indication can also indicate that the second device does not include any other data, such as data intended to be read (e.g., identifier or sensor data).

[0020] In one embodiment, the first device may be configured to receive and process a predetermined data sequence in the first signal and a predetermined data sequence in the backscattered signal to derive an error estimate for the backscattered signal and transmit the error estimate in the feedback signal.

[0021] In one embodiment, the first device may be configured to pre-store a predetermined data sequence in the first device and receive the predetermined data signal in the backscatter signal to derive an error estimate of the backscatter signal and transmit the error estimate in the feedback signal.

[0022] The predetermined data sequence may be a known data sequence and may have been received by the first device before receiving the sequence from the second device. This embodiment enables an error estimate to be obtained and an adjustment to the first signal to be decided. If the reception quality is good during the initialization phase, a data acquisition phase may not be required to obtain data for a particular second device. On the other hand, if the indication is used to indicate that the second device does not include the predetermined data sequence, energy may be saved.

[0023] In one embodiment, the excitation source system may be configured to transmit the first signal with a time delay relative to the second signal. This embodiment enables consideration of the path difference between the first signal and the second signal and / or the processing time delay (if any) at the second device.

[0024] In one embodiment, the excitation source system may be configured to perform beamforming of the first signal and the second signal. Beamforming enables pointing to a specific device. Beamforming is known, for example, in telecommunication systems, such as 5G telecommunication systems, where precoding matrix processing is applied to direct the signal to a specific target.

[0025] In one embodiment, the stimulus system is configured to receive a control capacity request from a first device and to provide a control capacity indication to the first device.

[0026] In one embodiment, the first device is configured to transmit a control capacity request to a stimulus source system and to receive a control capacity indication from the stimulus source system.

[0027] This embodiment allows the first device to determine whether the excitation source system is controllable, ie whether the first signal can be adjusted to manage the reception quality at the first device.

[0028] In one embodiment, the excitation source system may be configured to transmit a first signal adjusted according to one or more adjustment parameters to a first device and another second signal to a second device, wherein the another second signal is configured to trigger another backscatter signal.

[0029] In one embodiment, the first device may be configured to receive an adjusted first signal from the excitation source system and receive another backscattered signal containing data of the second device, wherein the another backscattered signal is enhanced by the adjusted first signal.

[0030] This embodiment relates to a data acquisition phase, wherein the adjustment of the first signal as determined during the initialization phase is used to enhance the probability of good reception at the first device of data from the second device.

[0031] In one embodiment, the excitation source system can be configured to include or be connected to a smart reflective surface RIS so as to obtain an adjusted first signal by adjusting the first signal according to one or more adjustment parameters. The RIS can be used to control the first signal by controlling the reflection of the incoming signal by the excitation source to achieve control of the first signal, thereby generating an adjusted first signal. That is, if it is determined that the first signal is adjusted and necessary, for example, when the excitation source itself is not controllable for managing reception quality, the RIS is particularly useful during the data acquisition phase.

[0032] In one embodiment, the excitation source system can be configured to include or be connected to an orchestration system that is configured to orchestrate multiple excitation sources in the excitation source system with respect to the transmission of at least one of the first signal, the second signal, the adjusted first signal, and the other second signal. When multiple devices are used in the system, the orchestration system can be used to enhance the backscatter communication of the entire system. Such multiple excitation sources can be antenna arrays, for example, multi-output antenna arrays, such as MIMO antenna arrays.

[0033] In one embodiment, the excitation source system may be implemented at least partially in a telecommunication system, such as a 4G, 5G, or 6G telecommunication system.

[0034] In one embodiment, the first device may be a 3GPP compliant device such as a user equipment UE, which is configured to wirelessly communicate with a 3GPP compliant telecommunication network such as a 4G, 5G or 6G telecommunication network.

[0035] The excitation source system may include one or more base stations in a telecommunications network that may already be used for backscatter communications in the desired area and provide the capabilities for providing and adjusting the first signal as disclosed herein.

[0036] One aspect of the present disclosure relates to a method in an excitation system, the method comprising the steps of transmitting a first signal to a first device and transmitting a second signal to a second device. The second signal may be configured to excite the second device to generate a backscatter signal that can be received by the first device. The method may further include the steps of receiving a feedback signal from the first device and determining feedback information from the feedback signal based on the received first excitation signal and the backscatter signal. Another step may involve determining one or more adjustment parameters based on the feedback information to obtain an adjusted first signal, the adjusted first signal being used to manage the reception quality of another backscatter signal at the first device that is triggered by another second signal from the excitation source system.

[0037] Another aspect of the disclosure relates to a method in a first device configured to read data from a second device via backscatter communication, wherein the backscatter communication is triggered by an external excitation source system. The steps in the first device may include receiving a first signal from the excitation source system and receiving a backscatter signal from the second device. Further steps may include transmitting a feedback signal to the excitation source system, the feedback signal enabling the excitation source system to determine feedback information based on the received first excitation signal and the backscatter signal.

[0038] A further aspect of the disclosure relates to a system comprising an excitation source system as disclosed herein, at least one first device, and one or more second devices. The excitation source system is configured to transmit a first signal to the first device and transmit a second signal to the second device. The first device is configured to read data from the at least one second device via backscatter communication, wherein the backscatter communication is triggered by an external excitation source system. The second device contains data of the first device and is configured to receive the second signal to trigger a backscatter signal of the first device containing the data.

[0039] The excitation source system is configured to receive a feedback signal from a first device, which enables the excitation source system to determine feedback information based on the received first excitation signal and backscatter signal and to determine one or more adjustment parameters based on the feedback information to obtain an adjusted first signal, which is used to manage the reception quality of another backscatter signal at the first device triggered by another second signal from the excitation source system.

[0040] The first device is configured to receive a first signal from the excitation source system and a backscattered signal from the second device and transmit a feedback signal to the excitation source system, the feedback signal enabling the excitation source system to determine feedback information based on the received first excitation signal and the backscattered signal.

[0041] The second device is configured to receive the second signal to trigger a backscatter signal from the first device containing the data.

[0042] Further embodiments of a system comprising an excitation source system, a first device and at least one second device are described herein with respect to the excitation source system and the first device, respectively.

[0043] It should be noted that the first device may be configured to control the excitation source system as to how to adjust the first signal.

[0044] In an embodiment, the excitation source system is configured to transmit a first signal to a first device and transmit a second signal to a second device, wherein the second signal is configured to excite the second device to generate a backscatter signal that can be received by the first device. The excitation source system can be configured to receive a feedback signal from the first device. The feedback signal can enable the excitation source system to determine feedback information based on the received first excitation signal and the backscatter signal, and the feedback information can include adjustment parameters. The excitation source system can be configured to apply these adjustment parameters based on the feedback information to obtain an adjusted first signal, and the adjusted first signal is used to manage the reception quality of another backscatter signal at the first device that is triggered by another second signal from the excitation source system.

[0045] In an embodiment, the first device is configured to read data from the second device via backscatter communication, wherein the backscatter communication is triggered by an external excitation source system. The first device may be configured to receive a first signal from the excitation source system, receive a backscatter signal from the second device, and determine one or more adjustment parameters for adjusting the first signal based on the received first signal and the backscatter signal, and transmit a feedback signal containing the one or more adjustment parameters to the excitation source system.

[0046] As will be understood by those skilled in the art, aspects of the present invention may be embodied as a system, method or computer program product. Therefore, aspects of the present invention may take the form of a complete hardware embodiment, a complete software embodiment (including firmware, resident software, microcode, etc.) or a combination of software and hardware embodiments generally referred to herein as a "circuit", "module" or "system". The functions described in this disclosure may be implemented as an algorithm executed by a processor / microprocessor of a computer. In addition, aspects of the present invention may also take the form of a computer program product implemented in one or more computer-readable media, the computer-readable medium having a computer-readable program code embodied thereon (e.g., stored).

[0047] Any combination of one or more computer-readable media can be used.Computer-readable media can be computer-readable signal media or computer-readable storage media.Computer-readable storage media can be, for example, but not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing.More specific examples of computer-readable storage media can include, but are not limited to, the following: electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.In the context of the present invention, computer-readable storage media can be any tangible medium that can contain or store programs used by or in combination with instruction execution systems, devices or equipment.

[0048] A computer-readable signal medium may include a propagated data signal having a computer-readable program code embodied therein (e.g., in baseband or as part of a carrier wave). Such a propagated signal may take any of a variety of forms, including but not limited to electromagnetic, optical, or any suitable combination thereof. 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 convey a program (for use by or in connection with an instruction execution system, device, or apparatus).

[0049] Can use any suitable medium transmission to be embodied in the program code on computer readable medium, this medium includes but is not limited to any suitable combination of wireless, wired, optical fiber, cable, RF etc. or aforementioned.The computer program code for performing the operation of each aspect of the present invention can be written in any combination of one or more programming languages, and these one or more programming languages ​​comprise such as Java, Smalltalk, C++ and such as conventional process programming languages ​​such as " C " programming language or similar programming languages.Program code can be performed completely on personal computer, partly on personal computer, perform as independent software package, partly on personal computer and partly on remote computer or perform completely on remote computer or server.In the latter case, remote computer can be connected to personal computer by any type of network (comprising local area network (LAN) or wide area network (WAN)), or can be connected to external computer (for example, using Internet service provider through the Internet).

[0050] Aspects of the present invention are described below with reference to the flowchart and / or block diagram of the method, device (system) and computer program product according to an embodiment of the present invention. It should be understood that each frame of the flowchart and / or block diagram and the combination of frames in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable data processing device, specifically a microprocessor or a central processing unit (CPU), to produce a machine so that instructions executed via a processor of a computer, other programmable data processing device or other equipment create a device for implementing the function / action specified in one or more frames of the flowchart and / or block diagram.

[0051] These computer program instructions may also be stored in a computer-readable medium, which can instruct a computer, other programmable data processing device, or other equipment to function in a particular manner, so that the instructions stored in the computer-readable medium produce a manufactured article including instructions, which implement the functions / actions specified in one or more boxes of the flowchart and / or block diagram.

[0052] The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus, or other device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide a process for implementing the functions / actions specified in the flowchart and / or one or more block diagram blocks.

[0053] The flow charts and block diagrams in the accompanying drawings show the architecture, functions and operations of the possible implementation methods of the system, method and computer program product according to various embodiments of the present invention. In this regard, each frame in the flow chart or block diagram can represent a module, a fragment or a code portion, which includes one or more executable instructions for implementing (multiple) specific logical functions. It should also be noted that in some alternative implementations, the functions indicated in the frame may not occur in the order indicated in the figure. For example, depending on the functions involved, the two frames shown in succession can actually be executed substantially simultaneously, or sometimes the two frames can be executed in reverse order. It should also be noted that each frame of the block diagram and / or flow chart and the combination of frames in the block diagram and / or flow chart can be implemented by a combination of a system based on special hardware or special hardware and computer instructions that perform specific functions or actions.

[0054] Furthermore, a computer program for executing the method described herein and a non-transitory computer-readable storage medium storing the computer program are provided.

[0055] Unless otherwise explicitly stated, elements and aspects discussed for or with respect to a particular embodiment may be appropriately combined with elements and aspects of other embodiments. Embodiments of the present invention will be further described with reference to the accompanying drawings, which will schematically illustrate embodiments according to the present invention. It will be understood that the present invention is not limited to these specific embodiments in any way. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Various aspects of the invention will be explained in more detail with reference to exemplary embodiments shown in the accompanying drawings, in which:

[0057] Figure 1 is a schematic illustration of a system including an excitation source system, a first device, and a second device as disclosed herein;

[0058] FIG. 2A to FIG. 2C They are Figure 1 A more detailed schematic illustration of an example of an excitation source system, a first device, and a second device of the illustrated system;

[0059] Figure 3 is a timing diagram illustrating steps of a method for improving reception of a backscattered signal by a first device from a second device;

[0060] Figure 4 is a more detailed diagram of possible steps of a method for improving reception of a backscattered signal by a first device from a second device; and

[0061] Figure 5 An example of a processing system according to an embodiment of a stimulus system or a first device or a portion thereof is depicted. DETAILED DESCRIPTION

[0062] Figure 1 1 is a schematic diagram of a backscatter communication system 10, which includes one or more excitation source systems 100, one or more first devices 200, and one or more second devices 300. Optionally, the excitation source 100 can be under the control of the orchestration system 120. A reconfigurable smart surface (RIS) 130 can be provided as part of the backscatter communication system 10 or as the excitation source system 100. Typically, the number of second devices 300 is quite large and greatly exceeds the number of excitation source systems 100, and may exceed the number of first devices 200. The second devices 300 may, for example, include ambient energy IoT devices, which are battery-free devices with limited energy storage capabilities (possibly including a capacitor), where energy is provided, for example, by harvesting radio waves. Such ambient energy IoT devices preferably have low complexity.

[0063] The excitation source system 100 may include a base station compliant with the 3GPP standard, such as a gNb of a 5G or 6G telecommunication system. The excitation source system 100 may include a plurality of components 110, which will be referred to as Figure 2A The communication with the first device 200 and the second device 300 may be performed through a radio interface of a telecommunication network using the base station system 100 of the system 10. The orchestration system 120 may be part of the telecommunication network.

[0064] Although the present disclosure primarily refers to the wireless transmissions of the source excitation system 100 as signals, those skilled in the art will appreciate that these signals may take the form of transmission beams. Beamforming is a well-known measure taken in 5G and more advanced telecommunications networks, and may be used to direct signals to a particular device 200, 300. For example, the skilled person will appreciate that the beams of the first signal and the second signal may be superimposed, and precoding weights may be applied, for example, to delay the signals.

[0065] It should also be noted that the excitation source system 100 may be a stand-alone system or a system that is itself connected to another network in a wired or wireless manner.

[0066] The orchestration system 120 is configured to orchestrate the operation of the various stimulus source systems 100. In the case where multiple systems and devices are connected within a network, data collection from a second device can be orchestrated in a manner that reduces interference. This situation may be more common when each activation of a second device requires an additional signal path between the stimulus source system 100 and the first device 200. The orchestration system 120 can perform queries to the device network and schedule resources appropriately.

[0067] The excitation source system 100 may transmit a first signal FS and a second signal SS. The first signal FS is transmitted to a first device 200, which may also be referred to as a reader or reader device 200. The second signal SS is transmitted to a second device 300, which may also be referred to as a tag or backscatter device 300. The second device 300 may contain data to be obtained by the first device 200 via backscatter communication BS. The second device 300 is stimulated by the second signal SS from the excitation source system 100, which triggers the transmission of a backscatter signal BS for a limited duration, as known to those skilled in the art.

[0068] In the initialization phase, the first device 200 transmits a feedback signal FBS to the excitation source system 100 to determine feedback information based on the received first excitation signal FS and the backscattered signal BS.

[0069] More specifically, the excitation source system 100 is configured to transmit a first signal FS to the first device 200 and to transmit a second signal SS to the second device 300 containing data to be collected by the first device 200. The second signal SS is configured to excite the second device 300 to generate a backscatter signal BS that can be received by the first device 200. The source excitation system 100 is configured to receive a feedback signal FBS from the first device 100. The feedback signal FBS may enable the excitation source system 100 to determine feedback information based on the first excitation signal FS and the backscatter signal BS received at the first device 200. The excitation source system 100 may be further configured to determine one or more adjustment parameters based on the feedback information to obtain an adjusted first signal. The adjusted first signal may enable management of the reception quality of another backscatter signal at the first device that is triggered by another second signal from the excitation source system 100, as will be referred to below. Figure 3 described in further detail.

[0070] From the perspective of the first device (reader device), the device 200 is configured to read data from a second device 300 in its vicinity via backscatter communication BS, wherein the backscatter communication is triggered by an external excitation source system 100. The first device 200 is configured to receive a first signal FS from the excitation source system 100 and to receive a backscatter signal BS from the second device 300. The first device 200 is configured to transmit a feedback signal FBS to the excitation source system 100, which enables the excitation source system 100 to determine feedback information based on the first excitation signal and the backscatter signal.

[0071] Where it was previously believed that the first signal FS from the excitation source system 100 was detrimental to the reception of the backscattered signal BS at the reader device 200, the inventors propose to use the first signal FS, i.e., to determine, if necessary, to adjust the first signal FS during the initialization phase based on feedback about the reception of the first signal FS and the backscattered signal BS at the reader device 200 during the initialization phase. By managing the reception quality at the reader device 200, the data reception during the data acquisition phase can be controlled when the adjusted first signal and the further second signal are transmitted. Thus, the reception of the backscattered signal BS at the reader device 200 can be improved.

[0072] If the source excitation system 100 itself cannot be controlled or reached to adjust the first signal FS, the reconfigurable smart surface RIS 130 can be employed to help form the adjusted first signal FS at least during the data acquisition phase, as will be referred to in Figure 3 In particular, the RIS 130 is controllable to adjust the transmission from the source excitation system 100 by changing at least one of the phase and amplitude of the first signal FS according to feedback information in the feedback signal FBS from the reader device 200. The RIS may be controlled by the first device 200.

[0073] Now refer to FIG. 2A to FIG. 2C as well as Figure 3 An embodiment of the operation of the backscatter communication system 10 will be described in further detail.

[0074] Figure 2A It includes Figure 1 Schematic representation of an excitation source system 100 of the plurality of components 110 shown. The excitation source system 100 includes a transceiver 140 for wirelessly communicating with a reading device 200 and a tag 300. The excitation source system 100 further includes a processor 150 and a data storage device 160. The processor 150 is configured to execute various algorithms 171 to 173 shown as a virtual algorithm storage 170. These algorithms are typically implemented as software code executable by the processor 150. Figure 3 Some steps are shown in which some of these algorithms are used. It should be noted that the excitation source system 100 can be configured to perform more or fewer algorithms than disclosed herein.

[0075] The data storage device 160 may include one or more of the following data 161 to 163 .

[0076] The data storage device 160 may include signal parameters 161 of the first signal FS and the second signal SS, such as signal strength, phase, etc. In particular, the signal parameters may include signal beam parameters, including a beam vector describing the beam direction, beam strength, and beam phase (or beam delay). Signal parameters, such as beam parameters, may be applicable to each first device 200 and second device 300. Beamforming enables pointing to a specific device. Beamforming is known, for example, in telecommunication systems, such as 5G telecommunication systems, where precoding matrix processing is applied to direct the signal to a specific target. Beamforming may be applied to the first signal FS and / or the second signal SS from the excitation source system.

[0077] The data storage device 160 may also contain one or more adjustment parameters 162 obtained from the feedback signal FBS or derived from information therein for one or more reader devices 200. These adjustment parameters may include parameters for adjusting the first signal FS to obtain an enhanced signal at the reader device 200 in question, for example, parameters for constructive interference, such as one of phase (difference), signal strength and / or signal-to-noise ratio (SNR).

[0078] The data storage device 160 may also contain error threshold parameters and a predetermined data sequence 163. These may be used to determine whether it is indeed necessary to adjust the first signal FS based on information obtained from the reader device 200 (eg from the feedback signal FBS).

[0079] It should be noted that the data storage device 160 does not necessarily contain each of the above data. In some embodiments, similar data (such as a predetermined data sequence) can be stored or retrieved in the first device 200 and / or the second device 300, as will be understood by the skilled person. Without limitation, some examples of this situation will be described in further detail below.

[0080] The stimulus source system 100 may include codes for one or more of the following algorithms in the algorithm memory 170 for execution by the processor 150 .

[0081] The adjustment estimation algorithm 171 may include code for determining adjustments to the first signal to improve reception of data in the backscattered signal BS of the second device 300 in the reader device 20 that has provided the feedback signal. These adjustments may relate to phase or phase difference and / or signal strength.

[0082] It should be understood that the feedback signal FBS from the reader device 200 may include measurement data or processed measurement data about the first signal and the backscattered signal. For example, the feedback signal may include raw measurement data, such as signal strength, signal phase, etc. of each signal, and may also include processed signal data, such as signal strength difference, phase difference, etc. The nature of the feedback signal depends, for example, on the capacity of the excitation source system and the first device. In some embodiments, the feedback information may include one or more of the adjustment parameters derived at the first device, which adjustment parameters may be applied by the excitation source system when received in the feedback signal.

[0083] Depending on the information in the feedback signal FBS, the adjustment estimation algorithm may include one or more sub-algorithms, including, for example, a phase difference estimation algorithm, a signal-to-noise ratio SNR algorithm, and an error estimation algorithm.

[0084] The phase difference estimation algorithm may calculate the phase difference between the first signal FS and the backscattered signal BS and generate a value for adjusting the phase of the first signal FS to obtain an adjusted first signal.

[0085] The SNR algorithm may calculate the SNR of the combined signal at the reader device 200 and generate an adjusted signal strength value for the first signal.

[0086] The error estimation algorithm calculates the error level in the data of the received backscatter signal BS based on the predetermined data sequence and the error threshold parameter.If the backscatter signal BS is correctly received at this stage, the excitation source system can conclude that no adjustment of the first signal is required.

[0087] The signal generation algorithm 172 may include code for generating at least a first signal adjusted with respect to phase and / or signal strength based on the adjustment parameters. If the adjusted signal is a signal beam, the signal generation algorithm may generate adjusted beam parameters.

[0088] One or more additional algorithms 173 may be present in the excitation source system 100 to further improve the performance of the backscatter system 10 .

[0089] It should be noted that the algorithm memory 170 does not necessarily include each of the above algorithms. In some embodiments, similar algorithms (such as adjustment estimation algorithms) may be included in the first device 200, as will be understood by the skilled person. Without limitation, some examples of this situation will be described in further detail below.

[0090] Figure 2B2 is a schematic illustration of a first device 200 (i.e., a reader device). The reader device 200 includes a transceiver 210 for wirelessly communicating with the excitation source system 100 and the tag 300. The reader device 200 further includes a processor 220 and a data storage device 230. The processor 220 is configured to execute various algorithms 241 to 242, which are shown as a virtual algorithm memory 240. These algorithms are typically implemented as software codes that can be executed by the processor 220. Figure 3 Some steps are shown in which some of these algorithms are used. It should be noted that the reader device 200 can be configured to perform more or fewer algorithms than disclosed herein.

[0091] The data storage device 230 may include one or more of the following data 231 to 232 .

[0092] The data storage device 230 may also include one or more adjustment parameters 231 measured based on characteristics from the first signal and the backscattered signal. These adjustment parameters may include parameters for adjusting the first signal FS to obtain an enhanced signal at the reader device 200 in question, for example, parameters for constructive interference, such as one of phase (difference), signal strength and / or signal-to-noise ratio (SNR). These adjustment parameters may be sent to the excitation source system 100 in the feedback signal FBS so that it is applied by the system when generating the adjusted first signal.

[0093] The data storage device 230 may also contain error threshold parameters and / or predetermined data sequences 232. These may be used to determine whether an adjustment of the first signal FS is actually required.

[0094] The reader device 200 may include code in the algorithm memory 240 for one or more of the following algorithms for execution by the processor 220 .

[0095] The adjustment estimation algorithm 241 may include code for determining an adjustment for the first signal to improve reception of data in the backscattered signal BS of the second device 300 in the reader device 20 that has provided a feedback signal having a modulation parameter applied by the excitation source system. The adjustment may be related to the phase or phase difference and / or signal strength of the adjusted first signal.

[0096] It should be understood that the feedback signal FBS from the reader device 200 may include measurement data or processed measurement data about the first signal and the backscattered signal. For example, the feedback signal may include raw measurement data, such as signal strength, signal phase, etc. of each signal, and may also include processed signal data, such as signal strength difference, phase difference, etc. The nature of the feedback signal depends on, for example, the capacity of the excitation source system and the first device. If the raw measurement data or processed measurement data is sent in the feedback signal FBS for determining (multiple) adjustment parameters in the excitation source system 100, the reader device 200 itself may not need an adjustment estimation algorithm for such communication. On the other hand, in some embodiments, the feedback information may include one or more of the adjustment parameters derived at the first device using the adjustment algorithm therein. The (multiple) adjustment parameters may be applied by the excitation source system when received in the feedback signal. In such an embodiment, the excitation source system 100 may not need an adjustment estimation algorithm for this link.

[0097] The adjustment estimation algorithm may include one or more sub-algorithms, including, for example, a phase difference estimation algorithm, a signal-to-noise ratio SNR algorithm, and an error estimation algorithm. These algorithms may process raw measurement data such as the phase and SNR of the first signal FS and the backscattered signal BS.

[0098] The phase difference estimation algorithm may calculate the phase difference between the first signal FS and the backscattered signal BS and generate a value for adjusting the phase of the first signal FS to obtain an adjusted first signal.

[0099] The SNR algorithm may calculate the SNR of the combined signal at the reader device 200 and generate an adjusted signal strength value for the first signal.

[0100] The error estimation algorithm calculates the error level in the data of the received backscatter signal BS based on a predetermined data sequence and an error threshold parameter.

[0101] One or more additional algorithms 242 may be present in the excitation source system 100 to further improve the performance of the backscatter system 10. An example of another algorithm 262 may include a measurement algorithm for deriving the phase, signal strength, noise, etc. of incoming signals such as the first signal FS and the backscatter signal BS, and possibly processing these measurements into a phase difference, signal-to-noise ratio, etc. to be included in the feedback signal FBS.

[0102] It should be noted that the algorithm memory 240 does not necessarily contain every one of the above algorithms. In some embodiments, similar algorithms (such as adjustment estimation algorithms) may be included in the excitation source system 100, as will be understood by the skilled person. Without limitation, some examples of this will be described in further detail below.

[0103] Figure 2C is a schematic illustration of a second device 300 configured for backscatter communication. The second device 300 may be an ambient IoT device, an RFID device, an NFC device, and is also referred to herein as a tag device. The device 300 is configured to receive a second signal SS from the excitation system 100 to provide power. The device 300 includes a power collection part 310, a processing part 320, and a storage part 330 configured to store data. Power lines to these parts are indicated by solid lines, and signal lines are indicated by dashed lines.

[0104] The device 300 also includes at least one communication section for generating a backscatter signal, which is assumed to be contained in Figure 2C The second device 300 may include additional parts or functions, such as at least one sensor 340 (or a connector). It should be understood that the second device 300 may include multiple sensors 340 or connectors. Examples of sensors include position sensors, temperature sensors, humidity sensors, light sensors, pressure sensors, motion sensors, etc. A timestamp generator may also be a function available in the device for including a timestamp in the data transmission.

[0105] It should be understood that the backscatter device 300 may include more or fewer parts. In essence, the backscatter device is configured to be excited from an external signal (such as the second signal SS) to generate a backscatter signal BS for the reader device 200. The device may have limited (if any) energy storage capabilities (possibly including one or more capacitors), where the energy is provided by harvesting radio waves (e.g., from the excitation source system 100). The backscatter device 300 may not be able to store any significant power provided to it, and may use the provided power almost immediately to complete its actions. The backscatter device 300 may be equipped with beamforming capabilities.

[0106] about Figure 3 The timing diagram of FIG. 1 illustrates various aspects of the operation of the backscatter communication system 10, including aspects of each participating system and device. For example, the dashed line indicates the separation of the initialization phase from the data acquisition phase.

[0107] In general, the excitation source system 100 may be configured to receive a control capacity request from the first device 200 and provide a control capacity indication to the first device 200. This embodiment allows the first device 200 to determine whether the excitation source system 100 is controllable, i.e., whether the first signal can be adjusted to manage the reception quality at the first device 200.

[0108] therefore, Figure 3An optional step S1 is depicted, which may involve control and control check operations between the excitation source system 100 and the reader device 200. Examples of such communications involve the reader device 200 verifying the control capabilities of the excitation source system 100 and / or the excitation source system verifying the control capabilities of the reader device. The reader device 200 may find that the excitation source system 100 is capable of generating an adjusted first signal based on the feedback signal FBS, if necessary, which contains raw or processed measurement data from the reader device 200. In addition, step S1 may be used to obtain appropriate signal parameters (such as beam parameters) to communicate with the reader device 200.

[0109] The communication of step S1 may further be used to exchange predetermined data sequences. The predetermined data sequences may be forwarded, for example, from the stimulation source system 100 to the reader device 200 in order to be stored there in the data storage means 232 for future use.

[0110] In step S2, the excitation source system 100 transmits an excitation signal (second signal, for example, beam signal) SS to the backscatter device 300. The second signal SS triggers the backscatter device 300 to transmit a backscatter signal BS.

[0111] In step S3 , the excitation source system 100 transmits an excitation signal (a first signal, for example, a beam signal) FS to the reader device 200 .

[0112] Step S5 involves a processing step in the reader device 200. Processing step S5 may involve executing one or more of the algorithms 241 to 242 as defined above. The selection of the algorithm(s) to be executed may depend on the information obtained during step S1.

[0113] In step S6, the reader device 200 transmits a feedback signal FBS to the excitation source system 100. The information in the feedback signal can be used by the excitation source system 100 to adjust the first signal FS to improve the reception of the backscattered signal BS in the data acquisition phase. The information in the feedback signal FBS can include raw measurement data from the reader device regarding the first signal FS and the backscattered signal BS during the initialization phase, processed measurement data, and / or one or more adjustment parameters.

[0114] In general, the feedback information obtained at the excitation source system 100 can be related to the phase difference between the first signal FS and the backscattered signal BS at the reader device 200. The adjustment parameter derived from the feedback information can be related to the phase shift of the first signal FS to obtain the constructive interference between the adjusted first signal and another backscattered signal at the first device, as shown in the following step S10. By notifying the excitation source system 100 that the first signal FS obtains the phase required for the constructive interference of the phase-adjusted first signal and another backscattered signal, the reception quality at the first device 200 can be enhanced. The feedback information obtained at the excitation source system 100 can be further related to at least one of the signal-to-noise ratio SNR of the backscattered signal and the error estimate of the backscattered signal. Both the SNR and the error estimate can be used to manage the reception quality of the backscattered signal at the first device. For example, if the SNR is low, the first signal FS can be adjusted in phase and amplitude to enhance the reception quality. If the error estimate indicates that the reception quality is already good during the initialization phase, the first signal FS can be slightly adjusted or even not adjusted.

[0115] Step S7 involves a processing step in the excitation source system 100. Processing step S7 may involve executing one or more of the algorithms 161 to 163 as defined above. The selection of the algorithm(s) to be executed may depend on the information obtained during step S1.

[0116] The data acquisition phase may begin once one or more adjustment parameters are obtained at the excitation source system 100. The initialization phase (ie, the phase of obtaining adjustment parameters) may be repeated several times, for example, alternating with the data acquisition phase or under the control of a management system.

[0117] In step S8 , the excitation source system again transmits the second signal SS, which again triggers the backscatter signal BS in step S9 .

[0118] In step S10, the adjustment of the first signal FS is such that the data in the backscattered signal BS can be obtained in an improved manner (for example, by obtaining a constructive interference (by adjusting the phase of the first signal FS) Figure 3 The star symbol in ) indicates reception. Other improvements (such as improved SNR) may also result from adjusting the first signal FS.

[0119] It should be noted that, in principle, it is also possible to phase shift the second signal SS or both the first signal FS and the second signal SS. However, this is disadvantageous under normal conditions, since the second signal SS (in most cases) traverses a longer path and is processed at the backscatter device 300. However, the inventors have envisioned that phase shifting the second signal SS may be useful in cases where the first signal FS is not a direct link and / or the processing delay in the backscatter device 300 is negligible.

[0120] The excitation source system 100 may be configured such that the first signal FS in step S4 includes a predetermined data sequence and the second signal SS in step S2 also includes the predetermined data sequence or an indication configured to trigger the second device 300 to include the predetermined data sequence in the backscatter signal BS. In the latter case, the second device 300 may pre-store the predetermined data sequence in the storage portion 330. The first device 200 may be configured to receive and process the predetermined data sequence in the first signal in step S4 and the predetermined data sequence in the backscatter signal BS in step S3 to derive an error estimate of the backscatter signal and transmit the error estimate in the feedback signal FBS in step S6. In one embodiment, the first device 200 may be configured to pre-store the predetermined data sequence in the first device 200 (e.g., in the storage device 232) and receive the predetermined data signal in the backscatter signal BS in step S3 to derive an error estimate of the backscatter signal BS and transmit the error estimate in the feedback signal FBS in step S6. The predetermined data sequence may be a known data sequence and may have been received by the first device 200 before receiving the sequence from the second device. This embodiment enables an error estimate to be obtained and an adjustment of the first signal FS to be decided.If the reception quality is good during the initialization phase, a data acquisition phase may not be needed to obtain data for a particular second device 300 .

[0121] exist Figure 3 In the embodiment, the excitation source system 100 is configured to transmit the first signal FS with a time delay (e.g., phase shift) relative to the second signal SS. This embodiment enables taking into account the path difference between the first signal and the second signal and / or the processing time delay (if any) at the second device 300.

[0122] Figure 4 There is shown a series of steps in a method for operating a backscatter communication system 10. The method first assumes that the positions of the first device and the second device have been estimated.

[0123] In operation O1, the excitation source system 100 and the reader device 200 are preconfigured to communicate with each other in order to obtain data from the backscatter device 300. In this way, the excitation source system 100 has obtained the necessary beam parameters to communicate with the reader device 200 and the backscatter device 300 through beamforming. The beam parameters can be obtained via typical downlink and uplink communications required to perform backscatter communications. For example, downlink beam scanning can be applied to obtain the best beam vector for each device, which is transmitted as a response in the uplink channel. Channel state information CSI can be used to determine the beam strength required for communication.

[0124] In the case where the excitation source system 100 and the reader device 200 are not pre-configured, a pre-configuration process may be performed in which the reader device 200 requests to connect with the excitation source system 100. The excitation source system 100 may initially transmit a signal to excite the backscatter device 300. The backscatter device 300 may transmit modulated data. The reader device 200 will obtain the data and may then broadcast a response to the excitation source system 100 to identify itself as an available reader device 200. The excitation source system may communicate with the reader device 200 and establish a connection to support receiving the data of the backscatter device 300.

[0125] In operation O2, the excitation source system 100 transmits a known data sequence to be used by the backscatter device 300 to both the backscatter device 300 and the reader device 200. Alternatively, the known data sequence may be obtained from the backscatter device 300. For example, the backscatter device 300 may have a limited memory library of one or more known data sequences. The excitation source system 100 may alternatively attach a codeword for triggering the backscatter device 300 to transmit the known data sequence stored therein. Alternatively, the excitation source system 100 may transmit a codeword for triggering the backscatter device 300 not to modulate the second signal SS but to continue to backscatter the second signal SS. This may reduce the processing energy required to modulate the second signal SS at the backscatter device 300 and improve network energy efficiency.

[0126] In operation O3, the excitation source system 100 transmits an excitation signal (i.e., the second signal SS) toward the backscatter device 300 through the beam of the backscatter device 300 using corresponding beam parameters, and transmits a delayed excitation signal (i.e., the first signal FS) toward the reader device 200 through the beam of the reader device 200. The beam of the backscatter device 300 and the beam of the reader device 200 may be superimposed by combining the beam vectors of both the backscatter device 300 and the reader device 200, wherein a beam delay is applied to the beam of the reader device 200 using a precoding weight.

[0127] Alternatively, during the initialization phase, the beam delay of the first signal FS may be zero. Optionally, an analytical or empirical data approach may be used to estimate the beam delay. Such an approach includes, for example, calculating the distance between the devices based on the position estimate and using these distances to determine the beam delay required for constructive interference, for example, determining the phase difference between the two paths (excitation source system 100-reader device 200 and excitation source system 100-backscatter device 300-reader device 200), where the delay is proportional to the difference in time and path distance. Another approach may be to obtain the phase shift between the beam of the backscatter device 300 and the beam of the reader device 200 from a previous communication, for example, using a phase difference estimation algorithm (such as algorithm 172).

[0128] In operation O4, the backscatter device 300 receives the excitation signal SS of the excitation source system 100 and modulates it with a known data sequence to output a modulated sequence signal, i.e., a backscatter signal BS. The modulated sequence signal is transmitted from the backscatter device 300 using backscatter communication. Optionally, if the backscatter device 300 is equipped with a beamforming capability, the backscatter device can direct the backscatter signal toward the reader device 200. As previously described, this step can be initiated by the excitation source system 100 transmitting a codeword to the backscatter device 300. Alternatively, in the case where the excitation source system 100 has instructed the backscatter device 300 to perform backscattering without modulation, this step can be initialized by the excitation source system 100 transmitting the necessary codeword to the backscatter device 300.

[0129] In operation O5, the reader device 200 receives the modulated sequence signal from the backscatter device 300 and the delayed excitation signal from the excitation source system 100. The reader device 200 obtains an estimate of the phase difference between the delayed excitation signal (first signal FS) and the modulated sequence signal (backscatter signal BS) using the phase difference estimation algorithm in the memory 240. To this end, the reader device 200 compares the received signals with each other to determine the level of the phase difference.

[0130] The reader device 200 may also obtain an SNR estimate for the received signal using an SNR estimation algorithm in the memory 240. Finally, the reader device 200 may extract the signal strength of the modulated sequence signal and divide it by the signal strength of the received noise.

[0131] The reader device 200 may also use an error estimation algorithm in the memory 240 to obtain an error estimate. The error estimate may be calculated by demodulating the received modulation sequence signal and comparing the signal with a known data sequence to determine the number of received error bits. Examples of this include bit error rate BER calculations and bit error rate calculations.

[0132] In operation O6 , the reader device 200 transmits the phase difference, the SNR estimate, and the error estimate as a feedback signal FBS to the excitation source system 100 .

[0133] The excitation source system 100 can compare the obtained error estimate with the error threshold in the storage device 163 using the error threshold algorithm in the memory 170 to determine the error indicator. When the error indicator indicates that the current error estimate is below the error threshold, that is, the reader device 200 is able to obtain the backscatter signal BS of the backscatter device 300 without substantial error, it may not be necessary to adjust the first signal FS. Alternatively, it can be determined that constructive interference is not required (not much constructive interference is required), so the strength of the first signal FS can be reduced. In the case where the beam strength of the first signal FS is negligible, the first signal FS can be deactivated because constructive interference is not required.

[0134] In operation O7, the excitation source system 100 uses the feedback signal FBS from the reader device 200 in the beam adjustment algorithm to determine the adjustment to the first signal beam required to enhance the constructive interference at the reader device 200 and reduce the error. The excitation source system 100 can obtain the adjustment (increase or decrease) to the first signal beam by measuring the phase difference and SNR estimate to obtain the constructive interference parameters in the storage device 160 that meet the optimal constructive interference level. The excitation source system 100 can use the error indicator within the beam adjustment algorithm to determine the necessary constructive interference amplitude. Alternatively, the constructive interference parameters may need to be calibrated or are unknown. In this case, the parameters of the first signal beam can be learned by repeating operations O2 to O6, iteratively adjusting and recording the feedback of the reader device 200.

[0135] The feedback signal FBS may also include adjustments to the first signal beam of the reader device 200 and possibly to the second signal beam of the backscatter device 300, assuming that changes required to maintain communication are measured. For example, the backscatter device 300 has moved or if the corresponding channel conditions have changed. Examples of such methods include using CSI, beam scanning, etc. Downlink transmissions may be used in operations O2 to O5 to obtain the necessary measurements.

[0136] In operation O8 , the excitation source system 100 adjusts the beam parameters of the beam of the reader device 200 using the adjustment parameters of the reader device 200 .

[0137] It should be noted that operation steps O2 to O8 may be performed in a different order or may include more or fewer steps.

[0138] In the above operation, the reader device 200 obtains the necessary (SNR estimate, error estimate and / or phase difference), which is then processed at the excitation source system 100 to calculate the signal strength and / or phase delay required for adjusting the first signal FS. Alternatively, the reader device 200 may be responsible for processing the data. In doing so, the following process may be performed.

[0139] The reader device 200 may query the excitation source system 100 to obtain the transmit power details. The reader device 200 then executes a beam adjustment algorithm as part of a response algorithm in a memory 240 in the reader device 200. The transmit power of the excitation source system 100 may be used to limit the recommended signal strength of the signal to the reader device 200. The reader device 200 transmits a feedback signal FBS, which now includes the output of the beam adjustment algorithm. The excitation source system 100 may now directly apply the feedback information to adjust the first signal FS.

[0140] Operation O7 or O8 may terminate the initialization phase. Operations O8 and O9 and O9 constitute the data acquisition phase.

[0141] In operation O9, the excitation source system 100 transmits an excitation signal to both the backscatter device 300 and the reader device 200 using the adjustment of the excitation beam from the excitation source system to the reader device 200. The backscatter device 300 receives the excitation signal of the excitation source system 100 and performs data modulation on it, and then backscatters the modulated data signal BS. The reader device 200 receives a stronger modulated data signal from the backscatter device 300 using the delayed excitation signal FS from the excitation source system 100 as constructive interference.

[0142] The parameter tuning process described for operations O2 to O7 / O8 may be iteratively repeated to maintain constructive interference at the reader device 200 before or after the data acquisition phase indicated in operation O9.

[0143] In one embodiment, the excitation source system 100 can be configured to include or be connected to an orchestration system, such as Figure 1 As shown in the optional system 120 in FIG. 1 , the orchestration system is configured to orchestrate multiple excitation sources in the excitation source system 100 with respect to the transmission of at least one of the first signal FS, the second signal SS, the adjusted first signal FS, and the other second signal SS. When multiple devices are used in the system, the orchestration system 120 can be used to enhance the backscatter communication of the entire backscatter communication system 10. Such multiple excitation sources can be antenna arrays, for example, multi-output antenna arrays, such as MIMO antenna arrays, but can also be a collection of separate base stations.

[0144] The orchestration system 120 may include at least a transceiver, a data storage device, and a processor configured to execute one or more orchestration algorithms. Examples of such algorithms are provided below. It should be understood that the orchestration system 120 may be part of the excitation source system 100 or may be included in the reader device 200.

[0145] In the case where multiple devices (stimulators, backscatter devices 300, and reader devices 200) are connected within a network, data collection from the backscatter devices 300 can be orchestrated in a manner that reduces interference. This is more common when each activation of the backscatter device 300 causes or requires the addition of a first signal path between the stimulus system 100 and the reader device 200. The orchestration system 120 may involve querying the network of devices and scheduling resources appropriately.

[0146] Application of the orchestration system 120 may require one or more additional components in the orchestration system. For example, a beam estimation algorithm may be applied that uses device data to predict beam paths for different combinations of the excitation source system 100, the reader device 200, and the backscatter device 300, i.e., beam path prediction. The device data may include the type of device (e.g., excitation source, reader device 200, backscatter device 300), the location of the device (which may be obtained using a positioning algorithm such as trilateration or triangulation), the operating frequency of the device, and / or the antenna characteristics of the device.

[0147] An algorithm for beam scheduling may also be used. The beam scheduling algorithm may use device data to allocate resources to devices (resource scheduling) in order to reduce interference. Given the device locations, the beam scheduling algorithm may take into account the relative energy required for each source to communicate with the backscatter device 300 and a designated reader device 200. The beam coordination algorithm may take into account pairing the excitation source system 100, the backscatter device 300, and the reader device 200 so that multiple backscatter device 300 tags may be excited simultaneously.

[0148] For example, a group of excitation source systems 100, backscatter devices 300, and reader devices 200 may be grouped together and assigned a time slot, provided that the second signal SS for the backscatter device 300, the first signal to the reader device 200, and the backscatter signal BS do not interfere with the signal (e.g., beam) generated by another group of excitation source systems 100, backscatter devices 300, and reader devices 200 communicating. This may be achieved using beam path predictions obtained from a beam estimation algorithm. A group of excitation source systems 100, backscatter devices 300, and reader devices 200 may be assigned a separate frequency channel to communicate in the frequency channel, so that another group of excitation source systems 100, backscatter devices 300, and reader devices 200 may also communicate simultaneously.

[0149] Prior to the initialization phase, the orchestration system 120 may query the network to obtain device data. This may be done via broadcast or a separate dedicated communication channel. An orchestration device may be used, which may be the stimulus source system 100 or the reader device 200. The device data may be transmitted by multiple devices in the network, for example, to the stimulus source system 100 via one or more reader devices. Alternatively, the device data may be (pre-)stored in a system database and requested by the orchestration system.

[0150] The orchestration system may constitute resource scheduling, wherein resources are scheduled for transmitting the first signal and the second signal of the excitation source system 100. For example, Figure 3 In step S1, a resource schedule may be provided to the first device and the second device. Optionally, to reduce overhead, the backscatter device 300 may be assigned the resource schedule only if its capabilities allow its use. For example, if the backscatter device 300 uses a single frequency channel, it will not need to know the frequency resources allocated in the resource schedule. If the backscatter device 300 is completely passive and has no memory to store the resource schedule, such a schedule is also not needed. Devices within the network may follow the resource schedule to avoid conflicts, interference, and / or minimize energy consumption.

[0151] In one embodiment of the present disclosure, the reader device 200 may activate the system to improve its reception of backscattered signals. In such an embodiment, the reader device 200 may verify with the excitation source system 100 that the source is controllable and, for example, capable of beamforming. To this end, the reader device 200 may store certain device conditions of the excitation source system 100 ("conditions of the excitation source system 100") in the storage device 230 required to achieve constructive interference. Examples of conditions of the excitation source system 100 may include data regarding the controllability of the source, the presence of an antenna array in the source, the beamforming capabilities of the source, etc. This status may be stored in the storage device 230. Figure 3 The search is performed in step S1.

[0152] Before the initialization phase, the reader device 200 can use the conditions of the excitation source system 100 to query the excitation source system 100 to obtain relevant parameter information. In the case where the returned data does not meet the conditions of the excitation source system 100, the system cannot be enabled. For example, if the communication reveals that the excitation source system 100 is uncontrollable, the reader device cannot enable the system. Alternatively, the reader device 200 can request the excitation source system 100 to assign the excitation task of the backscatter device 300 to another nearby excitation source system 100 or device, possibly via the orchestration system 120 (when available).

[0153] In one embodiment, the excitation source system 100 may be configured to include or be connected to a smart reflective surface RIS, so as to obtain an adjusted first signal FS by adjusting the first signal according to one or more adjustment parameters, such as Figure 1 As shown. RIS can be used to control the first signal FS by controlling the reflection of the incoming signal by the excitation source, thereby generating an adjusted first signal FS. That is, if it is determined that the first signal is adjusted and necessary, for example, when the excitation source itself is not controllable for managing reception quality, RIS is particularly useful during the data acquisition phase.

[0154] If the excitation source system 100 is controllable, the RIS 130 can still be used as an additional element within the system to control the first signal of the reader device 200, such as the beam vector of the first signal. This may correspond to the first signal in the initialization phase and the data acquisition phase.

[0155] In the case where the excitation source system 100 is not controllable, the RIS can be controlled by the reader device 200 to adjust the intensity and / or phase of the first signal FS from the excitation source system 100, thereby establishing a delayed excitation signal and achieving constructive interference at the reader device 200. The excitation source system 100 can emit an excitation signal including or consisting of a continuous sinusoidal waveform. Since the signal can be periodic, a delay of multiple wavelengths can be used to achieve constructive interference.

[0156] RIS 130 can be configured to be able to perform directional beamforming on incident signals, such as from an excitation source, and to be able to communicate wirelessly with multiple devices, such as antenna arrays, data storage devices, processors, and controllers. The controller can be equipped with a separate receiving antenna. The method for communicating with the controller and its coordinates ("controller information") can be stored on the data storage device of the RIS.

[0157] Characteristics of the RIS ("RIS parameters") may be stored on a data storage device of the RIS. The RIS parameters may include RIS dimensions, location and orientation of the RIS, properties of RIS antenna elements, etc. The excitation source system 100 may have obtained the necessary RIS parameters, beam parameters, and / or controller information for transmission to the reader device 200 via the RIS. In the event that the source is not controllable, the reader device 200 may initiate the connection process as described above and request the relevant RIS parameters.

[0158] RIS 130 may also be capable of executing one or more RIS algorithms. The constructive criteria algorithm may use the backscatter device 300, the reader device 200, and the RIS features to determine whether constructive interference from the non-controllable excitation source system 100 may be achieved using the RIS 130. If constructive interference can be achieved, the constructive criteria is met. An example of a constructive criteria may be a Boolean value, where a 'true' value indicates that the constructive criteria is met.

[0159] Since the RIS can delay the signal, constructive interference can be achieved if an excitation signal from the excitation source system 100 (obtained via the backscatter device 300 at the reader device 200) is received after the first signal obtained via the RIS. Therefore, if constructive interference can be achieved, the constructive criterion is met. The analysis of the communication range of the desired communication path using the location data of each device can be used to determine whether the constructive criterion can be met. The RIS may only be able to delay the excitation signal from the excitation source system 100 by a fixed amount. Therefore, this can be considered as a maximum threshold for the difference in communication paths. In the event that the constructive criterion is not met, the reader device 200 can communicate with the backscatter device 300 to increase the delay of the backscatter communication at the backscatter device 300.

[0160] In the case where the excitation signal of the excitation source system 100 is not a continuous sinusoidal signal, the reader device 200 can use the RIS parameters within the constructive criterion algorithm to determine whether constructive interference is achievable, i.e., whether the constructive criterion is met. It can be analyzed to effectively determine whether the backscattered signal BS received via the backscatter device 300 is longer than the first signal FS received via the RIS, i.e., whether the RIS can delay the excitation signal to achieve constructive interference.

[0161] If multiple RIS are available, a RIS selection algorithm may be applied to determine the best RIS for constructive interference. The best RIS may be determined analytically by comparing RIS parameters, for example, using location information that may be used to identify the nearest RIS. As described above, the RIS selection algorithm may take into account the maximum delay achievable by the RIS, which may affect the communication range of the RIS relative to the excitation source system 100, the backscatter device 300, and the reader device 200. In the case where multiple RIS are available, the excitation source system 100 may use the RIS parameters within the RIS selection algorithm to identify the best RIS for the task.

[0162] The boot may be performed by broadcasting a request to identify a local RIS device.

[0163] exist Figure 4 The operation of using RIS in the context of for example involves the following further steps.

[0164] In operation O3, a delayed excitation signal is transmitted toward the reader device 200 via the RIS 130. In the case where the excitation source system 100 is not controllable, the excitation signal has no delayed component.

[0165] In operation O5 , a delayed excitation signal from the excitation source system 100 is obtained at the reader device 200 via the RIS 100 .

[0166] In operation O6, the reader device 200 may transmit a feedback signal FBS to the excitation source system 100 via the RIS.

[0167] In the case where the excitation source system 100 is not controllable, the RIS must be updated to adjust the excitation signal of the excitation source system 100. Therefore, the process of adjusting the parameters may be performed at the reader device 200.

[0168] To this end, the following method steps may be performed. The reader device 200 may determine an error indicator and generate adjustments, which may then be shared with the RIS 130 via transmission to the RIS controller. The excitation source system 100 may use the beam parameters of the reader device 200 to adjust the first signal. For example, a beam vector of the beam of the reader device 200 may be transmitted to the RIS 130 to maintain a signal connection with the reader device 200. In the case where the excitation source system 100 is not controllable, the RIS 130 may use the feedback information to update its beam parameters.

[0169] In operation O9, the excitation source system 100 transmits an excitation signal to both the backscatter device 300 and the reader device 200, wherein the latter transmits via the RIS to which these adjustments are applied.

[0170] Figure 5 A block diagram illustrating an exemplary processing system (eg, the excitation source system 100 or the first device 200 for use in the backscatter communication system 100) according to the disclosed embodiments is depicted. Figure 5 As shown, the data processing system 50 may include at least one processor 51 coupled to a memory element 52 via a system bus 53. In this way, the processing system may store program codes in the memory element 52. Further, the processor 51 may execute program codes accessed from the memory element 52 via the system bus 53. In one aspect, the processing system may be implemented as a computer system suitable for storing and / or executing program codes. However, it should be understood that the processing system 50 may be implemented in the form of any system including a processor and a memory capable of performing the functions described in this specification.

[0171] The memory element 52 may include one or more physical memory devices, such as a local memory 54 and one or more mass storage devices 55. Local memory may refer to a random access memory or other (multiple) non-persistent memory device commonly used during the actual execution of the program code. The mass storage device may be implemented as a hard drive or other persistent data storage device. The processing system 50 may also include one or more cache memories (not shown) that provide temporary storage of at least some program codes to reduce the number of times that program codes must be retrieved from the mass storage device 55 during execution.

[0172] Input / output (I / O) devices, depicted as input device 56 and output device 57, may optionally be coupled to the processing system. Examples of input devices may include, but are not limited to, a keyboard, a pointing device such as a mouse, etc. Examples of output devices may include, but are not limited to, a monitor or display, speakers, etc. Input devices and / or output devices may be coupled to the processing system directly or through intervening I / O controllers.

[0173] In an embodiment, the input device and the output device may be implemented as a combined input / output device (in Figure 5 An example of such a combined device is a touch-sensitive display, sometimes referred to as a "touch screen display" or simply a "touch screen," that may be provided with a UE. In such an embodiment, input to the device may be provided by movement of a physical object (such as a stylus or a person's finger) on or near the touch screen display.

[0174] A network adapter 58 may also be coupled to the processing system to enable it to couple to other systems, computer systems, remote network devices, and / or remote storage devices through an intervening private or public network. The network adapter may include a data receiver for receiving data transmitted by the system, device, and / or network to the processing system 50, and a data transmitter for transmitting data from the processing system 50 to the system, device, and / or network. Modems, cable modems, and Ethernet cards are examples of different types of network adapters that may be used with the processing system 50.

[0175] like Figure 5 As depicted in FIG. 5 , the memory element 52 may store an application 59. In various embodiments, the application 59 may be stored in the local memory 54, one or more mass storage devices 55, or separate from the local memory and the mass storage device. It should be understood that the processing system 50 may further execute an operating system (OS) that may facilitate the execution of the application 59. Figure 5). The application 59 implemented in the form of executable program code may be executed by the processing system 50 (eg, by the processor 51). In response to executing the application, the processing system 50 may be configured to perform one or more operations or method steps described herein.

[0176] In one aspect of the invention, one or more components in an orchestration system as disclosed herein may represent processing system 60 as described herein.

[0177] Various embodiments of the present invention may be implemented as a program product for use with a computer system, wherein the (multiple) programs of the program product define the functions of the embodiments (including the methods described herein). In one embodiment, the (multiple) programs may be contained on various non-transitory computer-readable storage media, wherein, as used herein, the expression "non-transitory computer-readable storage medium" includes all computer-readable media, with the only exception of temporarily propagated signals. In another embodiment, the (multiple) programs may be contained on various transient computer-readable storage media. Illustrative computer-readable storage media include, but are not limited to: (i) non-writable storage media on which information is permanently stored (e.g., a read-only memory device within a computer, such as a CD-ROM disk, a ROM chip, or any type of solid-state non-volatile semiconductor memory readable by a CD-ROM drive); and (ii) writable storage media on which variable information is stored (e.g., a flash memory, a floppy disk within a floppy disk drive or a hard disk drive, or any type of solid-state random access semiconductor memory). The computer program may run on the processor 61 described herein.

[0178] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when the terms "comprise" and / or "comprising" are used in this specification, they specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0179] The corresponding structures, materials, operations, and equivalents of all means or step-plus-function elements in the claims are intended to include structures, materials, or operations that perform functions in combination with other declared elements that are explicitly claimed. The description of the embodiments of the present invention has been presented for the purpose of illustration, but the description is not intended to be exhaustive or limited to the disclosed forms of implementation. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the claims. The selection and description of the embodiments are intended to best explain the principles of the invention and some practical applications, and when suitable for the specific purpose contemplated, enable other persons of ordinary skill in the art to understand the invention for various embodiments with various modifications.

Claims

1. An excitation source system, configured to transmit a first signal to a first device and a second signal to a second device, wherein: The second signal is configured to excite the second device to generate a backscattered signal that can be received by the first device, wherein the excitation source system is configured to perform the following operations: receiving a feedback signal from the first device, the feedback signal enabling the excitation source system to determine feedback information based on the received first excitation signal and the backscattered signal, One or more adjustment parameters are applied or determined based on the feedback information to obtain an adjusted first signal for managing reception quality of another backscattered signal at the first device triggered by another second signal from the excitation source system.

2. The excitation source system according to claim 1, wherein: The feedback information is related to a phase difference between the first signal and the backscattered signal, and wherein at least one of the one or more adjustment parameters is related to a phase shift of the first signal to obtain constructive interference between the adjusted first signal and the further backscattered signal.

3. The excitation source system according to claim 1 or 2, wherein: The feedback information is related to at least one of the following: a signal-to-noise ratio (SNR) of the backscattered signal; and An error estimate of the backscattered signal.

4. The excitation source system according to one or more of the preceding claims, wherein: The first signal comprises a predetermined data sequence; and The second signal includes the predetermined data sequence or indication, and the indication is configured to: triggering the second device to include the predetermined data sequence in the backscattered signal, or The second device is instructed not to include the predetermined data sequence in the backscatter signal.

5. Excitation source system according to one or more of the preceding claims, wherein: The excitation source system is configured to perform at least one of the following: transmitting the first signal with a time delay relative to the second signal; and Beamforming of the first signal and the second signal is performed.

6. Excitation source system according to one or more of the preceding claims, wherein: The stimulus system is configured to receive a control capacity request from the first device and to provide a control capacity indication to the first device.

7. Excitation source system according to one or more of the preceding claims, wherein: The excitation source system is configured to perform the following operations: transmitting a first signal adjusted according to the one or more adjustment parameters to the first device; and The further second signal is transmitted to the second device, wherein the further second signal is configured to trigger the further backscatter signal.

8. Excitation source system according to one or more of the preceding claims, wherein: The excitation source system includes one or more excitation sources, and further includes or is connected to at least one of the following: at least one smart reflective surface RIS configured to obtain the adjusted first signal by adjusting the first signal according to the one or more adjustment parameters; A scheduling system is configured to schedule a plurality of excitation sources in the excitation source system with respect to transmission of at least one of the first signal, the second signal, the adjusted first signal, and the further second signal.

9. Excitation source system according to one or more of the preceding claims, wherein: The excitation source system is at least partially implemented in a telecommunication system, such as a 4G, 5G or 6G telecommunication system.

10. A first device configured to read data from a second device via backscatter communication, wherein: The backscatter communication is triggered by an external excitation source system, wherein the first device is configured to perform the following operations: receiving a first signal from the excitation source system; receiving a backscattered signal from the second device; A feedback signal is transmitted to the excitation source system, wherein the feedback signal enables the excitation source system to determine feedback information based on the received first excitation signal and the backscattered signal, wherein, optionally, the feedback information includes at least one of one or more adjustment parameters for adjusting the first signal determined based on the received first excitation signal and the backscattered signal.

11. The first device according to claim 10, wherein: The feedback information is related to the phases of the first signal and the backscattered signal, the phase difference between the first signal and the backscattered signal, and / or the phase shift of the first signal.

12. The first device according to claim 10 or 11, wherein: The feedback information is further related to at least one of the following: a signal-to-noise ratio (SNR) of the backscattered signal; and An error estimate of the backscattered signal.

13. A first device according to one or more of the preceding claims 10 to 12, wherein: The first device is configured to perform at least one of the following operations: receiving and processing a predetermined data sequence in the first signal and a predetermined data sequence in the backscattered signal to derive an error estimate for the backscattered signal, and transmitting the error estimate in the feedback signal; A predetermined data sequence is pre-stored in the first device and the predetermined data signal is received in the backscatter signal to obtain an error estimate of the backscatter signal, and the error estimate is transmitted in the feedback signal.

14. A first device according to one or more of the preceding claims 10 to 13, wherein: The first device is configured to transmit a control capacity request to the source system and to receive a control capacity indication from the source system.

15. The first device according to one or more of the preceding claims 10 to 14, wherein: The first device is configured to perform the following operations: receiving a conditioned first signal from the excitation source system; Another backscatter signal containing data of the second device is received, wherein the another backscatter signal is enhanced by the adjusted first signal.

16. A first device according to one or more of claims 10 to 15, wherein: The first device is a device compliant with 3GPP standards, such as a user equipment UE, which is configured to wirelessly communicate with a telecommunication network compliant with 3GPP standards, such as a 4G, 5G or 6G telecommunication network.

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