Communication method and apparatus, and communication device, readable storage medium and program product

Abstract

The present application relates to a communication method and apparatus, and a communication device, a readable storage medium and a program product. The method comprises: receiving a first mixed signal, a first channel signal and a second mixed signal, wherein the first channel signal is a signal obtained by means of transmitting, to a receiving device and via a first channel, a first radio frequency signal that is sent by a radio frequency device, the second mixed signal is a signal obtained by means of transmitting, to the receiving device and via a second channel, second radio frequency signals that are sent by a tag device by means of a plurality of transmitting antennas, and the first mixed signal comprises the first channel signal and the second mixed signal; and on the basis of the first channel signal, demodulating the first mixed signal to obtain the second radio frequency signals in the second mixed signal that are sent by means of the transmitting antennas, wherein the second radio frequency signals carry position information of the corresponding transmitting antennas.

Description

Communication methods, apparatus, communication devices, readable storage media and program products

[0001] Related applications

[0002] This application claims priority to Chinese patent application filed on July 26, 2024, application number 202411013040X, entitled "Communication Method, Apparatus, Communication Device, Readable Storage Medium and Program Product", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of communication technology, and in particular to a communication method, apparatus, communication device, readable storage medium, and program product. Background Technology

[0004] With the development of communication technology, environmental backscatter communication systems have emerged. An environmental backscatter communication system includes an environmental radio frequency source, a backscatter transmitter, and a backscatter receiver. The backscatter transmitter can alternately communicate with the backscatter receiver between two states: reflection and non-reflection (i.e., absorption), thereby modulating and transmitting environmental radio frequency signals.

[0005] However, when multiple antennas are deployed on a backscatter transmitter, there is a problem of multi-antenna coupling. Summary of the Invention

[0006] In a first aspect, this application provides a communication method applied to a receiving device, the method comprising:

[0007] The receiver receives a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a first radio frequency signal transmitted by a radio frequency device and transmitted to the receiving device via a first channel; the second mixed signal is a second radio frequency signal transmitted by a tag device through multiple transmitting antennas and transmitted to the receiving device via a second channel; the first mixed signal includes the first channel signal and the second mixed signal.

[0008] The first mixed signal is demodulated based on the first channel signal to obtain the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0009] In one embodiment, the step of demodulating the first mixed signal based on the first channel signal to demodulate the second radio frequency signals transmitted by each of the transmitting antennas in the second mixed signal includes:

[0010] The first channel signal in the first mixed signal is eliminated to obtain the second mixed signal;

[0011] The second mixed signal is demodulated to obtain the second radio frequency signal transmitted by each of the transmitting antennas.

[0012] In one embodiment, demodulating the second mixed signal to obtain the second radio frequency signal transmitted by each of the transmitting antennas includes:

[0013] The first energy signal of the receiving antenna on the receiving device and the second energy signal received through the preset channel are determined based on the second mixed signal.

[0014] Based on the first energy signal and the second energy signal, the second radio frequency signal transmitted by each of the transmitting antennas is obtained.

[0015] In one embodiment, obtaining the second radio frequency signal transmitted by each of the transmitting antennas based on the first energy signal and the second energy signal includes:

[0016] The energy distribution of the first energy signal is determined based on the second energy signal;

[0017] Based on the energy distribution of the first energy signal, the maximum energy signal received on each of the receiving antennas is determined;

[0018] The maximum energy signal received by each of the receiving antennas is demodulated to obtain the second radio frequency signal transmitted by each of the transmitting antennas.

[0019] In one embodiment, determining the energy distribution of the first energy signal based on the second energy signal includes:

[0020] Using the second energy signal as a condition, determine the probability density distribution function of the energy signal received by each of the receiving antennas in the first energy signal;

[0021] The energy distribution of the first energy signal is obtained by multiplying the probability density distribution functions of the energy signals received by all the receiving antennas.

[0022] In one embodiment, the method further includes:

[0023] The second radio frequency signal transmitted by each of the transmitting antennas is demodulated to obtain the first radio frequency signal transmitted by the radio frequency device.

[0024] Secondly, this application provides a communication method applied to a tag device, the method comprising:

[0025] Receive the first radio frequency signal sent by the radio frequency device;

[0026] The first radio frequency signal is modulated based on the location information of multiple transmitting antennas to generate a second radio frequency signal;

[0027] The second radio frequency signal is transmitted to the receiving device through the plurality of transmitting antennas.

[0028] In one embodiment, the step of modulating the first radio frequency signal based on the location information of multiple transmitting antennas to generate a second radio frequency signal includes:

[0029] The first radio frequency signal is encoded according to the location information of each of the transmitting antennas to generate a second radio frequency signal carrying the location information of each of the antennas.

[0030] Thirdly, this application provides a communication device for use in a receiving device, the device comprising:

[0031] A first receiving module is configured to receive a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted to the receiving device via a first channel from a first radio frequency (RF) signal sent by an RF device; the second mixed signal is a signal transmitted to the receiving device via a second channel from a tag device through multiple transmitting antennas; the first mixed signal includes the first channel signal and the second mixed signal.

[0032] The demodulation module is used to demodulate the first mixed signal according to the first channel signal, and demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0033] Fourthly, this application provides a communication device for use in tag devices, the device comprising:

[0034] The second receiving module is used to receive the first radio frequency signal sent by the radio frequency device;

[0035] The modulation module is used to modulate the first radio frequency signal according to the position information of multiple transmitting antennas to generate a second radio frequency signal;

[0036] The transmitting module is used to transmit the second radio frequency signal to the receiving device through the plurality of transmitting antennas.

[0037] Fifthly, this application provides a communication device, which includes a receiving device and a processor;

[0038] The receiving device is configured to receive a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted to the receiving device via a first channel from a first radio frequency signal transmitted by a radio frequency device; the second mixed signal is a signal transmitted to the receiving device via a second channel from a second radio frequency signal transmitted by a tag device through multiple transmitting antennas; the first mixed signal includes the first channel signal and the second mixed signal.

[0039] The processor is configured to demodulate the first mixed signal according to the first channel signal, and demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0040] Sixthly, this application provides a communication device, which includes a receiving device, a processor, and a transmitter;

[0041] The receiving device is used to receive the first radio frequency signal sent by the radio frequency device;

[0042] The processor is configured to modulate the first radio frequency signal based on the position information of multiple transmitting antennas to generate a second radio frequency signal;

[0043] The transmitter is used to transmit the second radio frequency signal to the receiving device through the plurality of transmitting antennas.

[0044] In a seventh aspect, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the steps of the methods in any of the embodiments of the first to third aspects described above.

[0045] Eighthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the steps of the methods in any of the embodiments of the first to third aspects described above.

[0046] Details of one or more embodiments of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 is an application environment diagram of a communication method in one embodiment;

[0049] Figure 2 is a flowchart illustrating a communication method in one embodiment;

[0050] Figure 3 is a flowchart illustrating the demodulation step of the second mixed signal in one embodiment;

[0051] Figure 4 is a flowchart illustrating the second radio frequency signal determination step in one embodiment;

[0052] Figure 5 is a flowchart illustrating the demodulation step based on the maximum energy signal in one embodiment;

[0053] Figure 6 is a comparison chart of the bit error rates between the communication method in this embodiment of the application and the communication method in related technologies in one embodiment;

[0054] Figure 7 is a flowchart illustrating the demodulation step of the second radio frequency signal in one embodiment;

[0055] Figure 8 is a flowchart illustrating the communication method in another embodiment;

[0056] Figure 9 is a schematic diagram illustrating the principle of encoding the first radio frequency signal in one embodiment;

[0057] Figure 10 is a flowchart illustrating the communication method in one optional embodiment;

[0058] Figure 11 is a structural block diagram of a communication device in one embodiment;

[0059] Figure 12 is a structural block diagram of the communication device in another embodiment. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0062] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0063] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0064] With the development of communication technology, environmental backscatter communication systems have emerged. An environmental backscatter communication system includes an environmental radio frequency (RF) source, a backscatter transmitter (tag), and a backscatter receiver (reader). When both the backscatter transmitter and the backscatter receiver receive the environmental RF source signal, the backscatter transmitter can send data to the backscatter receiver based on that signal. The backscatter transmitter can alternate between a reflection state and a non-reflection (i.e., absorption) state to communicate with the backscatter receiver, thereby modulating and transmitting the environmental RF signal.

[0065] Traditional single-antenna backscatter transmitters suffer from low communication rates. Therefore, multiple antennas can be deployed on a backscatter transmitter to increase antenna gain and reduce the impact of multipath fading. However, deploying multiple antennas on a backscatter transmitter introduces multi-antenna coupling issues, causing information from different antennas to conflict during transmission, thus limiting the communication rate. Furthermore, in traditional multi-antenna backscatter communication systems, the transmitting antennas need high synchronization to achieve simultaneous data transmission. Simultaneous data transmission from multiple antennas generates high inter-channel interference, increasing decoding difficulty and system complexity.

[0066] The communication method provided in this application embodiment can be applied to the communication system shown in Figure 1. The communication system refers to an environmental backscatter communication system, which includes radio frequency (RF) devices, tag devices, and receiving devices that can communicate with each other. The RF devices may include, but are not limited to, environmental RF sources; the tag devices may include, but are not limited to, backscatter tags, and N transmitting antennas may be deployed on the tag devices; the receiving devices may include, but are not limited to, readers, and M receiving antennas may be deployed on the receiving devices. Referring to Figure 1, the RF device can transmit a first RF signal x to the receiving device through a first channel d.s (n), the radio frequency device can send the first radio frequency signal x to the tag device through the third channel f. s (n), thus, the tag device can send a signal based on the first radio frequency signal x to the receiving device through the second channel b. s (n) The second radio frequency signal x generated t (n)x s (n), and thus, the receiving device can receive data based on the first radio frequency signal x. s (n) and the second radio frequency signal x t (n)x s The first mixed signal y(n) is generated by (n). Where, This represents the first channel coefficient between the radio frequency device and the receiving device. This represents the second channel coefficient between the tag device and the receiving device. This represents the third channel coefficient between the radio frequency device and the tag device.

[0067] Those skilled in the art will understand that the structure shown in Figure 1 is merely a block diagram of a portion of the structure related to the solution of this application, and does not constitute a limitation on the network architecture to which the solution of this application is applied. The specific network architecture may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0068] In one embodiment, as shown in FIG2, a communication method is provided. Taking the application of this method to a receiving device in the communication system of FIG1 as an example, the method includes the following steps:

[0069] S201, receiving a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted from a first radio frequency signal sent by a radio frequency device to a receiving device via a first channel; the second mixed signal is a signal transmitted from a second radio frequency signal sent by a tag device through multiple transmitting antennas to a receiving device via a second channel; the first mixed signal includes the first channel signal and the second mixed signal.

[0070] The first channel signal is the first radio frequency signal transmitted by the radio frequency device and transmitted to the receiving device through the first channel d. For example, the first radio frequency signal can be an independently identically distributed (IID) circularly symmetric complex zero-mean white Gaussian noise (CSCG) random signal. The second mixed signal is the second radio frequency signal transmitted by the tag device through multiple transmitting antennas and transmitted to the receiving device through the second channel b. The second mixed signal is a backscattered signal modulated by the second channel. The transmitting antennas refer to the multiple antennas deployed on the tag device. The first mixed signal includes the first channel signal and the second mixed signal.

[0071] In this embodiment of the application, the radio frequency device can transmit a first radio frequency signal x to the receiving device through the first channel d. s (n), and the radio frequency device can also send the first radio frequency signal x to the tag device through the third channel f. s (n), thus, the tag device can collect the first radio frequency signal x emitted from the radio frequency device. s The energy of (n) is transmitted to the receiving device via the second channel b based on the first radio frequency signal x. s (n) The second radio frequency signal x generated t (n)x s (n), and thus, the receiving device can receive data based on the first radio frequency signal x. s (n) and the second radio frequency signal x t (n)x s The first mixed signal y(n) generated by (n), and the first radio frequency signal x received s (n) The first channel signal transmitted to the receiving device via the first channel d, and the second radio frequency signal x received. t (n)x s (n) The second mixed signal is transmitted to the receiving device via the second channel b. Optionally, the radio frequency device may send the first radio frequency signal to both the tag device and the receiving device simultaneously, or the radio frequency device may not send the first radio frequency signal to both the tag device and the receiving device simultaneously. Of course, the embodiments of this application do not limit the time for sending the first radio frequency signal.

[0072] S202, the first mixed signal is demodulated according to the first channel signal to obtain the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0073] The second radio frequency signal carries the location information of the corresponding transmitting antenna. For example, the location information may include, but is not limited to, the tag information or index information of the transmitting antenna. That is, it can be understood that each second radio frequency signal received by each receiving antenna deployed on the receiving device corresponds to each transmitting antenna.

[0074] In this embodiment, optionally, the receiving device can directly demodulate the first mixed signal based on the first channel signal to demodulate the second radio frequency (RF) signals transmitted by each transmitting antenna in the second mixed signal; alternatively, the receiving device can first demodulate the first mixed signal based on the first channel signal to demodulate the second mixed signal, and then demodulate the second mixed signal to demodulate the second RF signals transmitted by each transmitting antenna in the second mixed signal. Of course, this embodiment does not limit the specific implementation method for demodulating the second RF signals transmitted by each transmitting antenna.

[0075] In the above communication method, a first mixed signal, a first channel signal, and a second mixed signal are received. The first channel signal is a first radio frequency signal transmitted by a radio frequency device and transmitted to a receiving device via a first channel. The second mixed signal is a second radio frequency signal transmitted by a tag device through multiple transmitting antennas and transmitted to a receiving device via a second channel. The first mixed signal includes the first channel signal and the second mixed signal. The first mixed signal is demodulated based on the first channel signal to obtain the second radio frequency signals transmitted by each transmitting antenna in the second mixed signal. The second radio frequency signals carry the location information of the corresponding transmitting antennas. Because the second radio frequency signals carry the location information of the corresponding transmitting antennas, each receiving antenna deployed on the receiving device can accurately determine the corresponding transmitting antenna for each received second radio frequency signal. Therefore, the first mixed signal can be demodulated based on the corresponding transmitting antenna and the first channel signal, and the second radio frequency signals transmitted by each transmitting antenna in the second mixed signal can be accurately demodulated, thus avoiding the problem of multi-antenna coupling.

[0076] In one embodiment, a demodulation implementation is provided, as shown in Figure 3. The demodulation of the first mixed signal based on the first channel signal in S202 above, and the demodulation of the second radio frequency signals transmitted by each transmitting antenna in the second mixed signal, includes the following steps:

[0077] S301, the first channel signal in the first mixed signal is eliminated to obtain the second mixed signal.

[0078] In this embodiment, the receiving device can first determine the first mixed signal and the first channel signal, and then eliminate the first channel signal from the first mixed signal to determine the second mixed signal. The specific principle is as follows:

[0079] For example, the second radio frequency signal transmitted by the tag device through multiple transmitting antennas and transmitted to the receiving device via the second channel b can be expressed as the following equation (1):

[0080] Where Ps represents the average transmit power of the first radio frequency signal, x s This refers to the first radio frequency signal transmitted by the radio frequency device. The first radio frequency signal can be a random complex Gaussian vector.

[0081] Therefore, the signal received by the m-th receiving antenna on the receiving device, m = 1, 2, ..., M, can be expressed as the following equation (2):

[0082] Among them, y d，m (n) represents direct link interference from the radio frequency equipment, i.e., the first channel signal; w m (n) is the power of σ 2's baseband additive white Gaussian noise, i.e. Assuming the above noise w m (n) independent of signal y b,m (n) and y d，m (n), can be adopted This represents the received signal-to-noise ratio (SNR) of the direct link (i.e., the link corresponding to the first channel), and the signal-to-noise ratio (SNR) using... This represents the received signal-to-noise ratio (SNR) of the backscatter link (i.e., the link corresponding to the second channel). Therefore, the relative SNR between the backscatter link and the direct link can be expressed as Δγ = γ d / γ b Without loss of generality, assume Then equation (2) can be equivalent to y = HX + w. For X, the equivalent signal model of X(n) can be expressed as equation (3):

[0083] H can be expressed as the following formula (4):

[0084] Among them, H bsc =H b H f , This represents the second channel coefficient between the tag device and the receiving device. This represents the third channel coefficient between the radio frequency device and the tag device.

[0085] The following describes the steps for eliminating the first channel signal in the first mixed signal at the receiving device:

[0086] Since the equivalent complete channel matrix of the above communication system is non-invertible, the first channel signal of the radio frequency device can be obtained by using a zero-forcing (ZF) detector. The pseudo-inverse of the equivalent complete channel matrix is ​​shown in equation (5):

[0087] Therefore, the estimated equivalent first channel signal can be expressed as equations (6) and (7):

[0088] Based on this, the first channel signal in the first mixed signal can be removed to obtain the second mixed signal as shown in equation (8):

[0089] S302, demodulate the second mixed signal to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0090] In this embodiment, optionally, the receiving device can directly demodulate the second mixed signal according to the respective transmitting antennas corresponding to each second radio frequency signal to obtain the second radio frequency signal transmitted by each transmitting antenna; alternatively, the receiving device can first determine the energy signal corresponding to the receiving antenna on the receiving device, and then demodulate the second mixed signal according to the energy signal and the respective transmitting antennas corresponding to each second radio frequency signal to obtain the second radio frequency signal transmitted by each transmitting antenna. Of course, this embodiment does not limit the specific implementation method of demodulating the second mixed signal.

[0091] In this embodiment, the first channel signal in the first mixed signal can be eliminated to obtain the second mixed signal, and then the second mixed signal can be demodulated to accurately obtain the second radio frequency signal transmitted by each transmitting antenna.

[0092] In one embodiment, a method for demodulating the second mixed signal is provided, as shown in FIG4. The demodulation of the second mixed signal in S302 above to obtain the second radio frequency signal transmitted by each transmitting antenna includes the following steps:

[0093] S401, determine the first energy signal of the receiving antenna on the receiving device and the second energy signal received through the preset channel based on the second mixed signal.

[0094] In this embodiment, the receiving antenna refers to multiple antennas deployed on the receiving device; the first energy signal refers to the output signal of the energy detector at the receiving antenna; and the second energy signal refers to the energy signal received through a defined preset channel, where the preset channel is the channel corresponding to any one of the antennas in the second channel. b (n), determine the first energy signal on the m-th receiving antenna of the receiving device as r.m =|y bm | 2 Furthermore, the receiving device can also determine, based on the second mixed signal, the second energy signal received through the preset channel as...

[0095] S402, based on the first energy signal and the second energy signal, obtain the second radio frequency signal transmitted by each transmitting antenna.

[0096] In this embodiment, optionally, the receiving device can directly demodulate the first mixed signal based on the first energy signal and the second energy signal to obtain the second radio frequency signal transmitted by each transmitting antenna; alternatively, the receiving device can first determine the energy distribution of the first energy signal based on the first energy signal and the second energy signal, and then demodulate the first mixed signal based on the energy distribution of the first energy signal to obtain the second radio frequency signal transmitted by each transmitting antenna. Of course, this embodiment does not limit the specific implementation method for obtaining the second radio frequency signal transmitted by each transmitting antenna based on the first energy signal and the second energy signal.

[0097] In this embodiment, the first energy signal of the receiving antenna on the receiving device and the second energy signal received through a preset channel are determined based on the second mixed signal. Thus, the first mixed signal can be accurately demodulated based on the first energy signal and the second energy signal to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0098] In one embodiment, an implementation method for obtaining the second radio frequency signal transmitted by each transmitting antenna is provided, as shown in FIG5. The step S402 above, which obtains the second radio frequency signal transmitted by each transmitting antenna based on the first energy signal and the second energy signal, includes the following steps:

[0099] S501, determine the energy distribution of the first energy signal based on the second energy signal.

[0100] In this embodiment of the application, the receiving device can determine the energy distribution of the first energy signal based on the second energy signal. In one embodiment, S501 includes the following steps:

[0101] Using the second energy signal as a condition, determine the probability density distribution function of the energy signal received by each receiving antenna in the first energy signal;

[0102] The energy distribution of the first energy signal is obtained by multiplying the probability density distribution functions of the energy signals received by all receiving antennas.

[0103] In this embodiment of the application, the receiving device can use a second energy signal β m,n Given the condition, determine the first energy signal r on the m-th receiving antenna.m The conditional probability density function (PDF) can be expressed as follows (9):

[0104] Where I0(·) is the zeroth-order modified Bessel function of the first kind.

[0105] Therefore, since the receiving device is equipped with multiple antennas and the M branch is independent, the joint PDF of each first energy signal is calculated as follows: the probability density distribution function (i.e., the edge PDF) of the energy signals received by all receiving antennas is multiplied to obtain the energy distribution of the first energy signal.

[0106] S502, based on the energy distribution of the first energy signal, determine the maximum energy signal received on each receiving antenna.

[0107] In this embodiment of the application, the receiving device can determine the maximum energy signal received on each receiving antenna based on the energy distribution of the first energy signal. For example, the maximum energy signal is determined as follows:

[0108] To derive the detection metric, the receiving device follows the optimal maximum likelihood decision rule, which searches for β... n To maximize the natural logarithm of the likelihood function in the energy distribution of the first energy signal in the above equation, the maximum energy signal received on each receiving antenna is obtained, which can be specifically expressed as the following equation (10):

[0109] in, The estimated position information of the transmitting antenna is given. In order to apply incoherent detection to low-complexity receiving devices, the optimal decision rule in equation (10) needs to be simplified. The simplification method can be based on the asymptotic expansion of the logarithm of the Bessel function I0(·), for example, l n After the expansion is performed, the formula (10) corresponding to the suboptimal maximum likelihood decision rule becomes the following formula (11):

[0110] S503 demodulates the maximum energy signal received on each receiving antenna to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0111] In this embodiment of the application, the receiving device can set up an energy-based maximum likelihood detector based on the above formulas (9), (10), and (11). Thus, the maximum energy signal received on each receiving antenna can be demodulated according to the energy-based maximum likelihood detector to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0112] For example, as shown in Figure 6, Figure 6 is a comparison of the bit error rate (BER) between the communication method in this embodiment and the communication method in related technologies. For example, assuming the channel is an independent Rayleigh fading channel, i.e., the channel coefficient of each path is a CSCG random variable, and setting the number of receiving antennas M=8 for the receiving device, the number of transmitting antennas N=4 for the tag device, and the number of active antennas n=2, simulation results can verify the performance of the energy-based maximum likelihood detector designed in this embodiment. Combined with Figure 6, when using the detector proposed in this application, as the SNR (signal-to-noise ratio) increases from 0dB to 30dB, the BER can be reduced from 4.4*10^6 dB. -1 Reduced to 5.5*10 -3 In contrast, the bit error rate decreases more slowly when using the energy detector in related technologies; that is, the bit error rate of the energy detector in related technologies is very high, remaining at 10%. -1 The above suggests that using a maximum likelihood detector would require extremely high computational complexity and information about the radio frequency device, making it impractical for real-world applications.

[0113] In this embodiment, demodulation can be performed using a designed energy-based maximum likelihood detector, thereby accurately demodulating the second radio frequency signals transmitted by each transmitting antenna. The energy-based maximum likelihood detector in the multi-antenna environment backscattering system proposed in this application embodiment not only obtains the location information of the transmitting antennas without needing to acquire detailed information about the radio frequency equipment, but also has extremely low complexity, low hardware performance requirements, and excellent bit error rate performance. Therefore, it has lower usage costs and a wider range of application scenarios.

[0114] In one embodiment, a method for demodulating a second radio frequency signal is provided, as shown in Figure 7. The communication method further includes:

[0115] S203, demodulate the second radio frequency signal transmitted by each transmitting antenna to obtain the first radio frequency signal transmitted by the radio frequency device.

[0116] In this embodiment of the application, the receiving device can be based on each second radio frequency signal x t (n)x s (n) For each corresponding transmitting antenna, determine each second radio frequency signal x. t (n)x s (n) corresponds to the location information of the transmitting antenna x t (n), thereby enabling the transmission of the second radio frequency signal x to each transmitting antenna. t (n)x s(n) Demodulates the signal to obtain the first radio frequency signal x transmitted by the radio frequency device. s (n).

[0117] In this embodiment, the second radio frequency signals transmitted by each transmitting antenna can be demodulated to obtain the accurate first radio frequency signal transmitted by the radio frequency device.

[0118] The embodiments corresponding to Figures 2-7 above describe the communication method on the receiving device side. The following embodiments will specifically describe the communication method on the tag device side.

[0119] In one embodiment, as shown in FIG8, a communication method is provided. Taking the application of this method to the tag device in FIG1 as an example, the method includes the following steps:

[0120] S801 receives the first radio frequency signal sent by the radio frequency device.

[0121] In this embodiment of the application, the radio frequency device can send a first radio frequency signal x to the tag device through the third channel f. s (n), thus, the tag device can receive the first radio frequency signal x sent by the radio frequency device. s (n). Optionally, the tag device may receive the first radio frequency signal sent by the radio frequency device in real time; or, the tag device may also receive the first radio frequency signal sent by the radio frequency device at regular intervals. Of course, the embodiments of this application do not limit the specific implementation of receiving the first radio frequency signal.

[0122] S802 modulates the first radio frequency signal based on the position information of multiple transmitting antennas to generate a second radio frequency signal.

[0123] The second radio frequency signal refers to the signal based on the first radio frequency signal x. s (n) The second radio frequency signal x generated by modulation t (n)x s (n). The modulation method in this application embodiment can be a generalized space shift keying modulation method. In this application embodiment, the tag device can modulate the first radio frequency signal according to the position information of multiple transmitting antennas to generate a second radio frequency signal carrying the position information of each transmitting antenna.

[0124] S803 transmits a second radio frequency signal to a receiving device through multiple transmitting antennas.

[0125] In this embodiment, optionally, the tag device can transmit a second radio frequency signal to the receiving device in real time via the second channel b; or, the tag device can also periodically transmit a second radio frequency signal to the receiving device via the second channel b. Of course, this embodiment does not limit the specific implementation of transmitting the second radio frequency signal. Furthermore, the receiving device can receive signals based on the first radio frequency signal x.s (n) and the second radio frequency signal x t (n)x s The first mixed signal y(n) generated by (n), and the first radio frequency signal x received s (n) The first channel signal transmitted to the receiving device via the first channel d, and the second radio frequency signal x received. t (n)x s (n) The second mixed signal is transmitted to the receiving device via the second channel b.

[0126] In the above communication method, a first radio frequency (RF) signal is received from an RF device; the first RF signal is modulated according to the position information of multiple transmitting antennas to generate a second RF signal; and the second RF signal is transmitted to a receiving device through multiple transmitting antennas. Since the second RF signal carries the position information of the corresponding transmitting antenna, the tag device can transmit the second RF signal carrying the position information of each transmitting antenna to the receiving device through multiple transmitting antennas. Therefore, each receiving antenna deployed on the receiving device can accurately determine the corresponding transmitting antenna for each received second RF signal and demodulate the first mixed signal. Furthermore, it can accurately demodulate the second RF signal transmitted by each transmitting antenna in the second mixed signal, thus avoiding the problem of multi-antenna coupling.

[0127] In one embodiment, a modulation implementation is provided, wherein the "modulation of the first radio frequency signal based on the position information of multiple transmitting antennas to generate a second radio frequency signal" in S802 above includes the following steps:

[0128] The first radio frequency signal is encoded based on the position information of each transmitting antenna to generate a second radio frequency signal carrying the position information of each transmitting antenna.

[0129] In this embodiment, the tag device can determine the location information of each transmitting antenna and encode the first radio frequency signal using the location information of each transmitting antenna to generate a second radio frequency signal carrying the location information of each transmitting antenna. For example, as shown in Figure 9, which is a schematic diagram of the principle of encoding the first radio frequency signal in one embodiment, assuming the tag device has 4 transmitting antennas, and 2 antennas need to be activated when transmitting the second radio frequency signal (i.e., the gray transmitting antennas 1 and 2 in Figure 9), then the transmission... Spatial symbols or location information, for example, can be transmitted by mapping the indices of transmitting antennas to different first radio frequency signals, so that the indices of each transmitting antenna are carried in the second radio frequency signal, thereby transmitting the location information of each transmitting antenna. This avoids problems of synchronization and coupling between antennas. For example, the location information can be represented as a generalized space shift keying (SSK) coded vector. The N×1 SSK coded vector transmitted from the tag can be represented as: x t = [1 0·0·…·1·…·0], where there exists an n (number of active antennas) term that is not 0 and is equal to 1. Furthermore, for example, 00 can be used to represent the index when the active antenna is the first and second antenna, 01 can be used to represent the index when the active antenna is the first and third antenna, 10 can be used to represent the index when the active antenna is the first and fourth antenna, and 11 can be used to represent the index when the active antenna is the second and third antenna.

[0130] In this embodiment, the first radio frequency signal can be encoded based on the position information of each transmitting antenna to accurately generate a second radio frequency signal carrying the position information of each transmitting antenna. Thus, by mapping the transmitted second radio frequency signal to the antenna position information, coupling and synchronization problems between antennas can be avoided, thereby improving the communication rate.

[0131] Specifically, in this embodiment, the first radio frequency signal can be modulated by generalized space shift keying modulation, and the position information of each transmitting antenna can be parsed from the modulated second radio frequency signal. This allows for the differentiation of information transmitted by each transmitting antenna, effectively addressing the problem of mutual conflict that occurs during information transmission through multiple channels via different antennas.

[0132] In an optional embodiment, as shown in FIG10, a communication method is provided. Taking the application of this method to a receiving device in the communication system of FIG1 as an example, the communication method includes:

[0133] S21, receive a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted from a first radio frequency (RF) device to a receiving device via a first channel; the second mixed signal is a signal transmitted from a tag device via multiple transmitting antennas to a receiving device via a second channel; the first mixed signal includes the first channel signal and the second mixed signal; the second RF signal carries the location information of the corresponding transmitting antenna.

[0134] S22, the first channel signal in the first mixed signal is eliminated to obtain the second mixed signal;

[0135] S23, determine the first energy signal of the receiving antenna on the receiving device and the second energy signal received through the preset channel based on the second mixed signal;

[0136] S24, using the second energy signal as a condition, determine the probability density distribution function of the energy signal received by each receiving antenna in the first energy signal;

[0137] S25, perform a product operation on the probability density distribution functions of the energy signals received by all receiving antennas to obtain the energy distribution of the first energy signal;

[0138] S26, Based on the energy distribution of the first energy signal, determine the maximum energy signal received on each receiving antenna;

[0139] S27, Demodulate the maximum energy signal received on each receiving antenna to obtain the second radio frequency signal transmitted by each transmitting antenna;

[0140] S28, demodulate the second radio frequency signal transmitted by each transmitting antenna to obtain the first radio frequency signal transmitted by the radio frequency device.

[0141] In the above communication method, since the second radio frequency signal carries the location information of the corresponding transmitting antenna, each receiving antenna deployed on the receiving device can accurately determine the corresponding transmitting antenna of each received second radio frequency signal. Thus, the first mixed signal can be demodulated according to the corresponding transmitting antenna and the first channel signal of each second radio frequency signal. In turn, the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal can be accurately demodulated, thereby avoiding the problem of multi-antenna coupling.

[0142] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0143] Based on the same inventive concept, this application also provides a communication device for implementing the communication method described above. The solution provided by this device is similar to the solution described in the above method; therefore, specific limitations in one or more communication device embodiments provided below can be found in the limitations of the communication method described above, and will not be repeated here.

[0144] In one embodiment, as shown in FIG11, a communication device is provided for use with a receiving device, wherein:

[0145] The first receiving module 31 is used to receive a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted from a first radio frequency device to the receiving device via a first channel; the second mixed signal is a signal transmitted from a tag device via multiple transmitting antennas to the receiving device via a second channel; the first mixed signal includes the first channel signal and the second mixed signal.

[0146] The demodulation module 32 is used to demodulate the first mixed signal according to the first channel signal to demodulate the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0147] In one embodiment, the demodulation module includes:

[0148] The elimination unit is used to eliminate the first channel signal in the first mixed signal to obtain the second mixed signal;

[0149] The demodulation unit is used to demodulate the second mixed signal to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0150] In one embodiment, the demodulation unit includes:

[0151] The first determining subunit is used to determine, based on the second mixed signal, the first energy signal of the receiving antenna on the receiving device and the second energy signal received through a preset channel;

[0152] The second determining subunit is used to obtain the second radio frequency signal transmitted by each transmitting antenna based on the first energy signal and the second energy signal.

[0153] In one embodiment, the second determining subunit is specifically used for:

[0154] The energy distribution of the first energy signal is determined based on the second energy signal;

[0155] Based on the energy distribution of the first energy signal, the maximum energy signal received on each receiving antenna is determined;

[0156] The maximum energy signal received by each receiving antenna is demodulated to obtain the second radio frequency signal transmitted by each transmitting antenna.

[0157] In one embodiment, the "determining the energy distribution of the first energy signal based on the second energy signal" in the second determining subunit is specifically used for:

[0158] Using the second energy signal as a condition, determine the probability density distribution function of the energy signal received by each receiving antenna in the first energy signal;

[0159] The energy distribution of the first energy signal is obtained by multiplying the probability density distribution functions of the energy signals received by all receiving antennas.

[0160] In one embodiment, the communication device further includes:

[0161] The second radio frequency signal demodulation module is used to demodulate the second radio frequency signals transmitted by each transmitting antenna to obtain the first radio frequency signal transmitted by the radio frequency device.

[0162] In one embodiment, as shown in FIG12, a communication device is provided for use in a tag device, wherein:

[0163] The second receiving module 41 is used to receive the first radio frequency signal sent by the radio frequency device.

[0164] The modulation module 42 is used to modulate the first radio frequency signal according to the position information of multiple transmitting antennas to generate a second radio frequency signal.

[0165] The transmitting module 43 is used to transmit the second radio frequency signal to the receiving device through multiple transmitting antennas.

[0166] In one embodiment, the modulation module includes:

[0167] The encoding unit is used to encode the first radio frequency signal according to the position information of each transmitting antenna to generate a second radio frequency signal carrying the position information of each transmitting antenna.

[0168] Each module in the aforementioned communication device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the operations corresponding to each module.

[0169] In one embodiment, a communication device is provided, the communication device including a receiving device and a processor;

[0170] A receiving device is used to receive a first mixed signal, a first channel signal, and a second mixed signal; the first channel signal is a signal transmitted to the receiving device via a first radio frequency signal sent by a radio frequency device and transmitted through a first channel; the second mixed signal is a signal transmitted to the receiving device via a second channel by a tag device through multiple transmitting antennas; the first mixed signal includes the first channel signal and the second mixed signal.

[0171] The processor is used to demodulate the first mixed signal according to the first channel signal, and demodulate the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0172] In one embodiment, a communication device is provided, which includes a receiving device, a processor, and a transmitter;

[0173] A receiving device, used to receive a first radio frequency signal transmitted by a radio frequency device;

[0174] The processor is used to modulate the first radio frequency signal based on the position information of multiple transmitting antennas to generate a second radio frequency signal;

[0175] A transmitter is used to send a second radio frequency signal to a receiving device via multiple transmitting antennas.

[0176] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0177] The device receives a first mixed signal, a first channel signal, and a second mixed signal. The first channel signal is a first radio frequency signal transmitted by the radio frequency device and transmitted to the receiving device via the first channel. The second mixed signal is a second radio frequency signal transmitted by the tag device through multiple transmitting antennas and transmitted to the receiving device via the second channel. The first mixed signal includes the first channel signal and the second mixed signal.

[0178] The first mixed signal is demodulated based on the first channel signal to obtain the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0179] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0180] Receive the first radio frequency signal sent by the radio frequency device;

[0181] The first radio frequency signal is modulated based on the position information of multiple transmitting antennas to generate a second radio frequency signal;

[0182] The second radio frequency signal is transmitted to the receiving device through multiple transmitting antennas.

[0183] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0184] The device receives a first mixed signal, a first channel signal, and a second mixed signal. The first channel signal is a first radio frequency signal transmitted by the radio frequency device and transmitted to the receiving device via the first channel. The second mixed signal is a second radio frequency signal transmitted by the tag device through multiple transmitting antennas and transmitted to the receiving device via the second channel. The first mixed signal includes the first channel signal and the second mixed signal.

[0185] The first mixed signal is demodulated based on the first channel signal to obtain the second radio frequency signal transmitted by each transmitting antenna in the second mixed signal; the second radio frequency signal carries the position information of the corresponding transmitting antenna.

[0186] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0187] Receive the first radio frequency signal sent by the radio frequency device;

[0188] The first radio frequency signal is modulated based on the position information of multiple transmitting antennas to generate a second radio frequency signal;

[0189] The second radio frequency signal is transmitted to the receiving device through multiple transmitting antennas.

[0190] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetically resistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0191] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0192] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A communication method applied to a receiving device, the method comprising: receiving a first mixed signal, a first channel signal and a second mixed signal; the first channel signal being a signal of a first radio frequency signal transmitted by a radio frequency device and transmitted to the receiving device through a first channel; the second mixed signal being a signal of a second radio frequency signal transmitted by a tag device through a plurality of transmitting antennas and transmitted to the receiving device through a second channel; the first mixed signal comprising the first channel signal and the second mixed signal; demodulating the first mixed signal according to the first channel signal to demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carrying position information of a corresponding transmitting antenna. 2.The method of claim 1, wherein the demodulating the first mixed signal according to the first channel signal to demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal comprises: canceling the first channel signal in the first mixed signal to obtain the second mixed signal; demodulating the second mixed signal to obtain the second radio frequency signal transmitted by each of the transmitting antennas. 3.The method of claim 2, wherein the demodulating the second mixed signal to obtain the second radio frequency signal transmitted by each of the transmitting antennas comprises: determining a first energy signal of a receiving antenna on the receiving device according to the second mixed signal, and a second energy signal received through a preset channel; obtaining the second radio frequency signal transmitted by each of the transmitting antennas according to the first energy signal and the second energy signal. 4.The method of claim 3, wherein the obtaining the second radio frequency signal transmitted by each of the transmitting antennas according to the first energy signal and the second energy signal comprises: determining an energy distribution of the first energy signal according to the second energy signal; determining a maximum energy signal received by each of the receiving antennas according to the energy distribution of the first energy signal; demodulating the maximum energy signal received by each of the receiving antennas to obtain the second radio frequency signal transmitted by each of the transmitting antennas. 5.The method of claim 4, wherein the determining the energy distribution of the first energy signal according to the second energy signal comprises: determining a probability density distribution function of an energy signal received by each of the receiving antennas in the first energy signal based on the second energy signal; and multiplying the probability density distribution functions of the energy signals received by all the receiving antennas to obtain the energy distribution of the first energy signal. 6.The method of any one of claims 1-5, further comprising: demodulating the second radio frequency signal transmitted by each of the transmitting antennas to obtain the first radio frequency signal transmitted by the radio frequency device. 7.A communication method applied to a tag device, the method comprising: receiving a first radio frequency signal transmitted by a radio frequency device; modulating the first radio frequency signal according to position information of a plurality of transmitting antennas to generate a second radio frequency signal. transmitting the second radio frequency signals to a receiving device through the multiple transmitting antennas.

8. The method of claim 7, wherein the modulating the first radio frequency signal according to the position information of the multiple transmitting antennas to generate the second radio frequency signal comprises: encoding the first radio frequency signal according to the position information of each of the transmitting antennas to generate the second radio frequency signal carrying the position information of each of the antennas.

9. A communication apparatus applied to a receiving device, the apparatus comprising: a first receiving module configured to receive a first mixed signal, a first channel signal and a second mixed signal; the first channel signal being a signal of a first radio frequency signal transmitted by a radio frequency device and transmitted to the receiving device through a first channel; the second mixed signal being a signal of a second radio frequency signal transmitted by a tag device through multiple transmitting antennas and transmitted to the receiving device through a second channel; the first mixed signal comprising the first channel signal and the second mixed signal; a demodulating module configured to demodulate the first mixed signal according to the first channel signal to demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carrying the position information of the corresponding transmitting antenna.

10. A communication apparatus applied to a tag device, the apparatus comprising: a second receiving module configured to receive a first radio frequency signal transmitted by a radio frequency device; a modulating module configured to modulate the first radio frequency signal according to the position information of the multiple transmitting antennas to generate the second radio frequency signal; a transmitting module configured to transmit the second radio frequency signal to a receiving device through the multiple transmitting antennas.

11. A communication device comprising a receiving device and a processor; the receiving device configured to receive a first mixed signal, a first channel signal and a second mixed signal; the first channel signal being a signal of a first radio frequency signal transmitted by a radio frequency device and transmitted to the receiving device through a first channel; the second mixed signal being a signal of a second radio frequency signal transmitted by a tag device through multiple transmitting antennas and transmitted to the receiving device through a second channel; the first mixed signal comprising the first channel signal and the second mixed signal; the processor configured to demodulate the first mixed signal according to the first channel signal to demodulate the second radio frequency signal transmitted by each of the transmitting antennas in the second mixed signal; the second radio frequency signal carrying the position information of the corresponding transmitting antenna.

12. A communication device comprising a receiving device, a processor and a transmitter; the receiving device configured to receive a first radio frequency signal transmitted by a radio frequency device; the processor configured to modulate the first radio frequency signal according to the position information of the multiple transmitting antennas to generate the second radio frequency signal; the transmitter configured to transmit the second radio frequency signal to a receiving device through the multiple transmitting antennas.

13. A computer readable storage medium having stored thereon a computer program, wherein the computer program, when executed by a processor, implements the steps of the method of any one of claims 1 to 8.

14. A computer program product comprising a computer program which, when executed by a processor, implements the steps of the method according to any one of claims 1 to 8.

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