A backscattering communication method, device and equipment of a unique resolvable constellation pair

Abstract

The application discloses a method, device and equipment for backscatter communication of a uniquely decomposable constellation pair, which is applied to a multi-flow symbiotic backscatter communication system. The method comprises the following steps: reconstructing multiple user signals into to-be-transmitted signals which satisfy the unique decomposable constellation pair characteristics of the backscatter signals of an RIS array; transmitting the to-be-transmitted signals to the RIS array, fusing the to-be-transmitted signals with the backscatter signals to obtain a fused signal, and reflecting the fused signal to a receiving end; and decoding the receiving signal of the receiving end based on the SIC decoding rule and the unique decomposable constellation pair principle to obtain the to-be-transmitted signal. In the application, the multiple user signals are reconstructed into the to-be-transmitted signals which satisfy the unique decomposable constellation pair characteristics of the backscatter signals of the RIS array, the complexity of the receiving signal form is reduced, the decoding interference between the user signals and the backscatter signals is avoided, the effectiveness and reliability of signal transmission are improved, and a specific SIC decoding framework is constructed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and more particularly to a backscatter communication method, device and equipment of a uniquely decomposable constellation pair. BACKGROUND

[0002] With the rapid rise of the 5G era, the Internet of Things, as an important part of the new generation of communication technology, will connect billions of small devices to bring more convenience and intelligent experience to people's lives. However, spectrum scarcity and energy consumption problems have become two major challenges for current large-scale Internet of Things access.

[0003] The integration of intelligent metasurface (Reconfigurable Intelligent Surface, RIS) and backscatter communication technology is a very promising method to solve the above problems. RIS reconfigures the wireless propagation environment by software-controlled reflection. RIS is composed of a large number of low-cost passive reflection units, each of which can independently adjust the amplitude and / or phase change of the incident signal. By intelligently controlling the reflection of the signal, RIS can actively change the wireless channel, thereby providing new degrees of freedom for enhancing wireless communication performance and creating conditions for realizing an intelligent and programmable wireless environment. The advantage of RIS is that it can be densely deployed at a low cost and low energy consumption. RIS eliminates the traditional Radio Frequency (RF) link and baseband signal processing unit, so it does not need to use additional transmitting circuits, thereby reducing the cost and energy consumption of the device. In addition, the reflection elements of RIS can be densely arranged on a plane, so that more reflection channels can be realized in a given spatial range, further improving the performance of wireless communication.

[0004] However, in a multi-user signal scenario, there will be serious decoding interference between user signals and backscatter signals. At present, under the condition that the main system signal source transmits multi-user signals, when the intelligent metasurface is combined with the backscatter communication technology, in order to facilitate the modulation of the backscatter signal to the external radiation source main system signal at a specific frequency, the main system generally uses Non-Orthogonal Multiple Access (NOMA) signals, and the receiving end uses Successive Interference Cancellation (SIC) to decode each main system signal and backscatter signal. Although large-scale RIS can significantly improve the backscatter channel capacity, it will also introduce a lot of interference when decoding the main system signal; while small-scale RIS can reduce the interference of decoding the main system signal, but will limit the backscatter transmission rate, which will bring challenges to the improvement of transmission robustness and capacity. SUMMARY

[0005] In order to overcome at least one of the defects of the prior art or meet the needs of improvement, the present application provides a backscatter communication method, device and equipment of a uniquely decomposable constellation pair, which is used to solve the problem that in the prior art, in a multi-user signal scenario, there will be serious decoding interference between user signals and backscatter signals, which will affect the transmission robustness and capacity of information communication.

[0006] In order to achieve the above-mentioned purpose, according to a first aspect of the present application, a backscatter communication method of a uniquely decomposable constellation pair is provided, which is applied to a multi-stream coexisting backscatter communication system, and includes:

[0007] Respectively reconstructing a plurality of user signals into to-be-transmitted signals satisfying a uniquely decomposable constellation pair characteristic of backscatter signals of an RIS array;

[0008] Transmitting the to-be-transmitted signals to the RIS array, fusing the to-be-transmitted signals with the backscatter signals to obtain a fused signal, and reflecting the fused signal to a receiving end;

[0009] Decoding the receiving signal of the receiving end based on a SIC decoding rule and a uniquely decomposable constellation pair principle to obtain the to-be-transmitted signal.

[0010] In a possible implementation, the step of respectively reconstructing a plurality of user signals into to-be-transmitted signals satisfying a uniquely decomposable constellation pair characteristic of backscatter signals of an RIS array includes:

[0011] Constructing a phase shift keying constellation pair according to a uniquely decomposable constellation pair construction method;

[0012] Determining the backscatter signal and the to-be-transmitted signal from the phase shift keying constellation pair.

[0013] In a possible implementation, before the step of transmitting the to-be-transmitted signals to the RIS array and fusing the to-be-transmitted signals with the backscatter signals to obtain a fused signal, the method further includes:

[0014] Rescaling the maximum constellation point energy of the backscatter signal to a preset energy value;

[0015] Rescaling the constellation point energy of the to-be-transmitted signal based on the maximum constellation point energy of the backscatter signal.

[0016] In a possible implementation, the step of decoding the receiving signal of the receiving end based on a SIC decoding rule and a uniquely decomposable constellation pair principle to obtain the to-be-transmitted signal includes:

[0017] Decoding the fused signal with the maximum power coefficient from the receiving signal according to a maximum ratio combining linear detection method;

[0018] Canceling the decoded receiving signal and obtaining the to-be-transmitted signal one by one from the receiving signal based on a SIC decoding rule.

[0019] In a possible implementation, the method for decoding the fusion signal of the maximum power coefficient from the received signal according to the maximum ratio combining linear detection method comprises:

[0020] measuring the signal power of the received signal, and determining the received signal of the maximum power coefficient from all the received signals;

[0021] based on the maximum ratio combining linear detection method, using a decoding matrix to decode the received signal of the maximum power coefficient to obtain the fusion signal.

[0022] In a possible implementation, the method for obtaining the to-be-transmitted signal from the received signal one by one based on the SIC decoding rule after canceling the decoded received signal comprises:

[0023] canceling the decoded received signal from the received signal to obtain the undecoded received signal;

[0024] based on the maximum ratio combining linear detection method, setting a decoding coefficient to obtain the user decoding signal from the undecoded received signal;

[0025] calculating the to-be-transmitted signal from the user decoding signal one by one in a preset order.

[0026] In a possible implementation, the method for constructing the phase shift keying constellation pair according to the uniquely decomposable constellation pair construction method comprises:

[0027] based on the phase shift keying constellation pair construction formula, constructing the phase shift keying constellation pair satisfying the uniquely decomposable feature.

[0028] According to the second aspect of the present application, a uniquely decomposable constellation pair backscatter communication device is also provided, which is applied to a multi-stream coexistence backscatter communication system, and comprises:

[0029] a reconstruction module configured to reconstruct a plurality of user signals into to-be-transmitted signals respectively satisfying the uniquely decomposable constellation pair feature with the backscatter signals of the RIS array;

[0030] a fusion module configured to emit the to-be-transmitted signals to the RIS array and the backscatter signals to obtain a fusion signal, and reflect the fusion signal to a receiving end;

[0031] a decoding module configured to decode the received signals of the receiving end based on the SIC decoding rule and the uniquely decomposable constellation pair principle to obtain the to-be-transmitted signals.

[0032] According to a third aspect of the present application, there is further provided a backscatter communication device of a uniquely resolvable constellation pair, comprising at least one processing unit, and at least one storage unit, wherein the storage unit stores a computer program which, when executed by the processing unit, causes the processing unit to perform the steps of any of the above-mentioned methods of backscatter communication of a uniquely resolvable constellation pair.

[0033] According to a fourth aspect of the present application, there is further provided a storage medium storing a computer program executable by an access authentication device, which, when executed on the access authentication device, causes the access authentication device to perform the steps of any of the above-mentioned methods of backscatter communication of a uniquely resolvable constellation pair.

[0034] In general, the above technical solutions conceived by the present application can achieve the following beneficial effects compared to the prior art:

[0035] The method of backscatter communication of a uniquely resolvable constellation pair provided by the present application reconstructs multiple user signals into a to-be-transmitted signal satisfying the unique resolvable constellation pair characteristic of the backscatter signal of the RIS array surface, and due to the application of the unique resolvable constellation pair, the SIC decoding does not need to be realized in the form of a separate user signal in the received signal at the receiving end, which reduces the complexity of the received signal form, the to-be-transmitted signal is transmitted to the RIS array surface and fused with the backscatter signal to obtain a fused signal, which avoids decoding interference between the user signal and the backscatter signal, improves the effectiveness and reliability of user information transmission, and decodes the received signal at the receiving end based on the SIC decoding rule and the principle of the unique resolvable constellation pair to obtain the to-be-transmitted signal, which realizes the one-by-one decoding of the to-be-transmitted signal by using the characteristics of the unique resolvable constellation pair, and effectively reduces the symbol error rate of the RIS-enabled backscatter symbiotic system under multiple users. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort based on these drawings.

[0037] Figure 1 A flowchart of an embodiment of the method of backscatter communication of a uniquely resolvable constellation pair provided by the present application is shown in the figure.

[0038] Figure 2 A structural diagram of an embodiment of the multi-stream symbiotic backscatter communication system provided by the present application is shown in the figure.

[0039] Figure 3A flowchart of an embodiment of the SIC decoding rule-based method for decoding received signals one by one according to the present application is shown in the figure;

[0040] Figure 4 A comparison chart of the symbol error rate of the backscatter communication method and an embodiment of the RIS symbiotic system (benchmark system 1) considering the direct link;

[0041] Figure 5 A comparison chart of the symbol error rate of the backscatter communication method and an embodiment of the 'block' RIS symbiotic system (benchmark system 2);

[0042] Figure 6 A structural diagram of an embodiment of the backscatter communication device for the unique decomposable constellation pair according to the present application is shown in the figure;

[0043] Figure 7 A structural diagram of the backscatter communication device for the unique decomposable constellation pair according to the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0044] In order to make the objects, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0045] The terms "first", "second", "third" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish different objects and are not used to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed or can optionally include other steps or units inherent to the process, method, product or device.

[0046] The present application provides a backscatter communication method, device and equipment for a unique decomposable constellation pair, which are described below respectively.

[0047] Please refer to Figure 1 , Figure 1 A flowchart of an embodiment of the backscatter communication method for a unique decomposable constellation pair according to the present application is shown in the figure. In a specific embodiment of the present application, a backscatter communication method for a unique decomposable constellation pair is disclosed, which is applied to a multi-flow symbiotic backscatter communication system, including:

[0048] S100, reconstructing multiple user signals into backscattered signals that satisfy the unique decomposable constellation pair characteristics of the to-be-transmitted signals on the RIS array surface;

[0049] S200, transmitting the to-be-transmitted signals to the RIS array surface and fusing the backscattered signals to obtain a fused signal, and reflecting the fused signal to the receiving end;

[0050] S300, decoding the receiving signal of the receiving end based on the SIC decoding rule and the unique decomposable constellation pair principle to obtain the to-be-transmitted signal.

[0051] In the above embodiment, based on the UDCP principle, a specific constellation diagram is designed for user signals, which needs to satisfy the condition that the original signal can be uniquely and efficiently decomposed at the receiving end through a specific algorithm (such as serial interference cancellation, SIC). This requires the distance between constellation points, arrangement, and structure of signal space to be carefully designed to reduce the bit error rate and improve system capacity. Using the designed UDCP, the signal of each user is reconstructed into a to-be-transmitted signal that meets the specific constellation pair characteristics. This process may involve linear transformation, phase adjustment, or amplitude modulation of the signal to ensure efficient backscattering at the RIS (Reconfigurable Intelligent Surface, intelligent metasurface) array surface.

[0052] After the RIS array surface receives signals from different users, it uses a large number of programmable elements (such as diodes) on it to intelligently modulate these signals to form a fused signal. In this process, the RIS adjusts the on-off state of each element to achieve precise control of signal superposition and reflection direction. The fused signal is reflected by the RIS array surface to the receiving end, and at this time the signal contains not only the original information of each user, but also the modulation information introduced by the RIS.

[0053] Based on the unique decomposable constellation pair principle and the SIC decoding rule, the receiving end starts the decoding process. SIC is an iterative decoding method that gradually restores the original signals of each user by layer-by-layer eliminating the interference of the strongest signal. In this step, using the characteristics of UDCP, the receiving end can accurately distinguish and restore the signal of each user even if they overlap in the frequency spectrum. In order to further improve the system performance, the receiving end may also need to perform post-processing, such as channel estimation and equalization, error correction, etc., to further improve the decoding accuracy and the robustness of the system.

[0054] Please refer to Figure 2 , Figure 2This is a schematic diagram of an embodiment of the multi-stream co-occurring backscatter communication system provided by the present invention. The system includes a transmitter S, a reflective RIS array, and a receiver D located on one side of the RIS array. The direct transmission link of the system is ignored. The reflective RIS array as a whole serves as the backscatter signal modulation region (abbreviated as BD region), and the number of reflecting units within the region is N, which can be dynamically adjusted according to system performance requirements.

[0055] The user signal travels from the transmitter S to the RIS array and from the RIS array to the receiver D, following a two-hop channel model. In the first-hop channel model, the transmitter S constructs the m user signals to be transmitted as signals from the RIS array. Transmitted signal that satisfies the property of unique decomposable pair And it is sent to the RIS array, where it interacts with the backscattered signal of the RIS array. Perform fusion forwarding, and The values ​​are for specific zodiac signs. and constellation points, and It is a constellation pair that satisfies the unique decomposability property, i.e., a fused signal. Unique decomposition is possible. In the second-hop channel model, RIS uses reflection coefficients to represent the received user signals. With its own backscattered signal They were respectively merged into And it is reflected back to the receiving end.

[0056] Compared with existing technologies, this embodiment provides a backscatter communication method based on a uniquely decomposable constellation pair. Multiple user signals are reconstructed into a transmittable signal that satisfies the uniquely decomposable constellation pair characteristic of the backscattered signal from the RIS array. Due to the application of the uniquely decomposable constellation pair, the receiver signal does not require a separate user signal form for SIC decoding, reducing the complexity of the received signal form. The transmittable signal is transmitted to the RIS array and fused with the backscattered signal to obtain a fused signal, avoiding decoding interference between the user signal and the backscattered signal, thus improving the effectiveness and reliability of user information transmission. Based on the SIC decoding rules and the principle of the uniquely decomposable constellation pair, the received signal at the receiver is decoded to obtain the transmittable signal. The characteristic of the uniquely decomposable constellation pair is used to achieve one-by-one decoding of the transmittable signal, effectively reducing the symbol error rate of the RIS-enabled backscatter co-occurrence system under multi-user conditions.

[0057] In some embodiments of the present invention, multiple user signals are reconstructed into a transmittable signal that satisfies the unique decomposable constellation pair characteristic with the backscattered signal of the RIS array, including:

[0058] constructing a phase shift keying constellation pair according to a uniquely decomposable constellation pair construction method;

[0059] determining a backscattering signal and a to-be-transmitted signal from the phase shift keying constellation pair.

[0060] In the above embodiments, the design of the uniquely decomposable constellation pair is based on the mathematical orthogonality or good decomposability principle, aiming to enable the signals of different users or different data streams to be clearly distinguished on the constellation diagram and reduce mutual interference. In PSK modulation, each symbol represents different data by changing the phase of the carrier. In order to construct a constellation pair that satisfies the uniquely decomposable characteristic, multiple phase sets can be designed, each set representing the signal space of one user. These sets should be as dispersed as possible on the phase plane to reduce the overlap and interference between different user signals.

[0061] In some embodiments of the present application, before the to-be-transmitted signal is fused with the backscattering signal to obtain a fused signal, the method further comprises:

[0062] scaling the maximum constellation point energy of the backscattering signal to a preset energy value;

[0063] scaling the constellation point energy of the to-be-transmitted signal based on the maximum constellation point energy of the backscattering signal.

[0064] In the above embodiments, since the RIS is a passive device, in actual engineering, the backscattering efficiency η and the reflection coefficient β of the RIS array surface cannot reach 1, i.e. and This will make it difficult to fuse and into Therefore, in order to ensure that the fused signal has the unique decomposability, the maximum constellation point energy of the backscattering signal is scaled to 1, and the corresponding constellation point energy of is amplified in proportion, and then the fused signal still has the unique decomposability.

[0065] In some embodiments of the present application, the to-be-transmitted signal is decoded from the received signal at the receiving end based on the SIC decoding rule and the principle of the uniquely decomposable constellation pair, comprising:

[0066] decoding the fused signal with the maximum power coefficient from the received signal according to the maximum ratio combining linear detection method;

[0067] subtracting the decoded received signal and obtaining the to-be-transmitted signal one by one from the received signal based on the SIC decoding rule.

[0068] In the above embodiments, since the received signal can come from multiple paths (including the direct path and the RIS reflection path), the receiving end will use the Maximal Ratio Combining (MRC) linear detection method to weight and combine the signals from different paths according to the channel estimation results. This step aims to maximize the signal-to-noise ratio of the combined signal, thereby improving the decoding performance. In the combined signal, according to the size of the power coefficient, the fusion signal with the maximum power can be identified. This signal usually corresponds to the user or data stream with the strongest channel gain. Using the characteristics of the unique decomposable constellation pair, the receiving end can decode the fusion signal and extract the data to be transmitted.

[0069] Once the fusion signal with the maximum power is successfully decoded, the receiving end will decode the user signals and the backscatter signals to be transmitted based on this signal . The fusion signal with the maximum power is subtracted from the original received signal to eliminate the influence of this signal on other signals to be decoded. This step is the core of SIC decoding, which improves the decoding quality of subsequent signals by gradually eliminating the interference of decoded signals. After eliminating the interference of the signal with the maximum power, the receiving end will process the remaining received signals in order of decreasing signal power. For each signal to be decoded, the receiving end will repeat the decoding and interference cancellation process described above until all signals to be transmitted are successfully decoded.

[0070] In some embodiments of the present application, the fusion signal with the maximum power coefficient is decoded from the received signal according to the Maximal Ratio Combining linear detection method, comprising:

[0071] Measuring the signal power of the received signal, determining the received signal with the maximum power coefficient from all received signals;

[0072] Based on the Maximal Ratio Combining linear detection method, using a decoding matrix to decode the received signal with the maximum power coefficient to obtain the fusion signal.

[0073] In the above embodiments, the channel coefficients from the transmitting source S to the RIS array and from the RIS array to the receiving end D are respectively set as and . Considering that the transmitting source simultaneously transmits m user signals, the nth received signal at the receiving end can be represented as:

[0074] ;

[0075] wherein, , is and the signal formed by fusion and forwarding, PS is the total power transmitted by the base station S, These are the power allocation coefficients for the signals of each main system. It is the backscattering efficiency of the RIS array. It is the reflection coefficient of the RIS array. The power is Complex white Gaussian noise (AWGN), i.e. .

[0076] To simplify the representation, define First, consider the fused signal with the highest power. Decoding is performed using a decoding matrix under MRC algorithm detection. ,Right now

[0077] ;

[0078] in, Fusion signal with maximum power coefficient The detection can be performed based on the following expression:

[0079] ;

[0080] It should be noted that A represents the original value of the signal. This represents the actual value of the signal received by the receiver of signal A. This represents the estimated value of signal A. Further explanations of these symbols will not be provided below.

[0081] Please see Figure 3 , Figure 3 This is a flowchart illustrating an embodiment of the present invention for decoding a received signal one by one based on the SIC decoding rule. In some embodiments of the present invention, the decoded received signal is eliminated and the signal to be transmitted is obtained one by one from the received signal based on the SIC decoding rule, including:

[0082] S301. Remove the decoded received signal from the received signal to obtain the undecoded received signal;

[0083] S302. Based on the maximum ratio combining linear detection method, the decoding coefficients are set to obtain the user decoded signal from the undecoded received signal;

[0084] S303. Calculate the signal to be transmitted one by one from the user decoded signal according to the preset order.

[0085] In the above embodiments, based on the above decoding estimation The user signal can be uniquely decomposed. and backscattered signal From the received signal In, subtract The following expression is obtained:

[0086] ;

[0087] Next, the receiving end detects according to the MRC detector, that is, the decoding coefficient The following expression can be obtained:

[0088] ;

[0089] Therefore, the to-be-transmitted signal Can be estimated by the following expression:

[0090] ;

[0091] Next, the decoded signal , The remaining fusion signal is decoded according to the power size in turn, and the general expression can be obtained by analogy as follows:

[0092] ;

[0093] Wherein, , .

[0094] In some embodiments of the present application, the phase shift keying constellation pair is constructed according to the unique decomposable constellation construction method, comprising:

[0095] The phase shift keying constellation pair satisfying the unique decomposable characteristic is constructed based on the phase shift keying constellation pair construction formula.

[0096] In the above embodiment, if the PSK constellations X and Y respectively meet:

[0097] ;

[0098] ;

[0099] Wherein r=p+q, the constellations X and Y constitute a pair of UFCP constellation pairs.

[0100] Please refer to Figure 4 , Figure 4 The error symbol rate comparison chart of the backscattering communication method provided by the present application and an embodiment of the RIS symbiotic system (benchmark system 1) considering the direct transmission link, please refer to Figure 5 , Figure 5 The error symbol rate comparison chart of the backscattering communication method provided by the present application and an embodiment of the “block” RIS symbiotic system (benchmark system 2).

[0101] Benchmark system 1: traditional RIS coexistence backscatter system with direct link, the main system signal relies on the direct link for transmission, and the RIS only has a reflection function and is used as a backscatter device unit (BD) to modulate and enhance the backscatter signal transmission in the coexistence system. Similarly, the number of RIS array units is consistent with the invention system.

[0102] Benchmark system 2: divide the units on the RIS array into BD area and enhance primary (EP) area, where the BD area modulates the backscatter signal onto the main system signal, and the EP area is used to enhance the main system signal. In order to ensure fairness, the total number of units in the EP area and the BD area is consistent with the invention system.

[0103] The simulation parameters are set as follows: it is assumed that all channels are independent and identically distributed complex Gaussian fading, i.e. and . Considering the influence of path loss effect, the path loss exponent is represented by , and and are obtained. Without loss of generality, the average channel power gain is set to . For benchmark system 1, the average channel power gain of the main system direct link is set to , and for benchmark system 2, the average gain of each hop channel is 0.25.

[0104] The simulation program code idea is as follows: set the parameters, respectively , generate random samples that obey the exponential distribution. Assume that the transmitter of the "unique decomposable constellation pair" system performs NOMA power allocation on the two user signals to be transmitted, and construct the signal form that satisfies the unique decomposable constellation pair under the same BPSK form. After the fusion of the backscatter signal of the RIS array, unique decomposition can be achieved, i.e. , and , where the constellation . Then the constellation point set of the fusion signal can be determined as

[0105]

[0106]

[0107] The constellation , constitutes a unique decomposable constellation pair with constellation C, i.e. and All can realize unique decomposition. The simulation obtains the change curve of the error symbol rate of the RIS-enabled symbiotic environment backscattering system under Rayleigh channel conditions using the traditional method and the "unique decomposable constellation pair" system of the application, as shown in Figure 4 、 Figure 5 It can be seen that the "unique decomposable constellation pair" system proposed in the application can effectively reduce the error symbol rate of the receiving end of the system and improve the transmission reliability of the system.

[0108] In summary, the unique decomposable constellation pair backscattering communication method provided by the application reconstructs a plurality of user signals into a to-be-transmitted signal satisfying the unique decomposable constellation pair characteristic of the backscattering signal of the RIS array surface, and due to the application of the unique decomposable constellation pair, the SIC decoding does not need to be realized in the form of a separate user signal in the received signal at the receiving end, reducing the complexity of the received signal form, fusing the to-be-transmitted signal to the RIS array surface and the backscattering signal to obtain a fusion signal, avoiding decoding interference between the user signal and the backscattering signal, improving the effectiveness and reliability of user information transmission, decoding the received signal at the receiving end based on the SIC decoding rule and the principle of the unique decomposable constellation pair to obtain the to-be-transmitted signal, and using the characteristics of the unique decomposable constellation pair to realize the one-by-one decoding of the to-be-transmitted signal, effectively reducing the error symbol rate of the RIS-enabled backscattering symbiotic system under multiple users.

[0109] In order to better implement the unique decomposable constellation pair backscattering communication method in the embodiments of the application, on the basis of the unique decomposable constellation pair backscattering communication method, please refer to Figure 6 、 Figure 6 The structure diagram of an embodiment of the unique decomposable constellation pair backscattering communication device provided by the application, the embodiment of the application provides a unique decomposable constellation pair backscattering communication device 600, which comprises:

[0110] The reconstruction module 610 is configured to reconstruct a plurality of user signals into a to-be-transmitted signal satisfying the unique decomposable constellation pair characteristic of the backscattering signal of the RIS array surface;

[0111] The fusion module 620 is configured to fuse the to-be-transmitted signal to the RIS array surface and the backscattering signal to obtain a fusion signal, and reflect the fusion signal to the receiving end;

[0112] The decoding module 630 is configured to decode the received signal at the receiving end based on the SIC decoding rule and the principle of the unique decomposable constellation pair to obtain the to-be-transmitted signal.

[0113] It should be noted that the apparatus 600 provided in the above embodiments can implement the technical solutions described in the above method embodiments, and the principles of the implementation of the above modules or units can be referred to the corresponding content in the above method embodiments, which will not be described here.

[0114] Please refer to Figure 7 , Figure 7 The structure diagram of the unique decomposable constellation pair backscatter communication device provided by the embodiment of the application. Based on the unique decomposable constellation pair backscatter communication method, the application further provides a unique decomposable constellation pair backscatter communication device. The unique decomposable constellation pair backscatter communication device can be a mobile terminal, a desktop computer, a notebook computer, a palm computer, a server, and other computing devices. The unique decomposable constellation pair backscatter communication device 700 includes a processor 710, a memory 720, and a display 730. Figure 7 Only part of the components of the battery highly real-time measurement synchronous tracking flight welding device is shown, but it should be understood that all the components shown are not required to be implemented, and more or less components can be alternatively implemented.

[0115] The memory 720 can be an internal storage unit of the unique decomposable constellation pair backscatter communication device 700 in some embodiments, such as a hard disk or a memory of the unique decomposable constellation pair backscatter communication device 700. The memory 720 can also be an external storage device of the unique decomposable constellation pair backscatter communication device 700 in other embodiments, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, and the like. Further, the memory 720 can include both an internal storage unit and an external storage device of the unique decomposable constellation pair backscatter communication device 700. The memory 720 is used to store application software and various data installed in the unique decomposable constellation pair backscatter communication device 700, such as program codes installed in the unique decomposable constellation pair backscatter communication device 700. The memory 720 can also be used to temporarily store data that has been output or will be output. In an embodiment, the memory 720 stores a unique decomposable constellation pair backscatter communication program 740. The unique decomposable constellation pair backscatter communication program 740 can be executed by the processor 710, thereby implementing the unique decomposable constellation pair backscatter communication method of the embodiments of the application.

[0116] The processor 710 may, in some embodiments, be a central processing unit (CPU), a microprocessor, or other data processing chip for running program codes stored in the memory 720 or processing data, such as performing the method of backscatter communication of uniquely resolvable constellation pairs, etc.

[0117] The display 730 may, in some embodiments, be an LED display, a liquid crystal display, a touch liquid crystal display, an OLED (Organic Light-Emitting Diode) touch, etc. The display 730 is used to display information of the backscatter communication device 700 of uniquely resolvable constellation pairs and to display a visualized user interface. The components 710-730 of the backscatter communication device 700 of uniquely resolvable constellation pairs communicate with each other through a system bus.

[0118] In an embodiment, the steps in the method of backscatter communication of uniquely resolvable constellation pairs as above are implemented when the processor 710 executes the backscatter communication program 740 of uniquely resolvable constellation pairs in the memory 720.

[0119] The embodiment also provides a computer readable storage medium having stored thereon a backscatter communication program of uniquely resolvable constellation pairs, which, when executed by a processor, implements the following steps:

[0120] Resolving a plurality of user signals into a plurality of to-be-transmitted signals respectively, wherein the to-be-transmitted signals and the backscatter signals of the RIS array satisfy the characteristic of uniquely resolvable constellation pairs;

[0121] Transmitting the to-be-transmitted signals to the RIS array, fusing the to-be-transmitted signals and the backscatter signals to obtain a fused signal, and reflecting the fused signal to a receiving end;

[0122] Decoding the received signal of the receiving end based on the SIC decoding rule and the principle of uniquely resolvable constellation pairs to obtain the to-be-transmitted signal.

[0123] The application also provides a computer readable storage medium having stored thereon a computer program, which, when executed by a processor, implements the steps of the above method. The computer readable storage medium may, but not limited to, any type of disk, including floppy disks, optical disks, DVDs, CD-ROMs, micro-drives, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0124] It should be noted that, for the foregoing method embodiments, the sequences of the described actions are not necessarily required to achieve the objects of the application, and certain acts can be performed in other sequences, or even concurrently. Additionally, the described embodiments are merely provided as examples, and not all of the actions listed can be required in all embodiments.

[0125] In the above embodiments, the description of each embodiment is focused on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0126] In several embodiments provided in the present application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely schematic. For example, the division of the units is only a logical function division. In actual implementation, another division manner can be adopted. For example, a plurality of units or components can be combined or integrated into another system, or some features can be omitted or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some service interfaces, devices or units, and can be electrical or other forms.

[0127] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0128] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0129] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable memory. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a memory and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present application. The aforementioned memory includes: a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0130] A person of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer readable memory, which can include a flash disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0131] The above is only exemplary embodiments of the present disclosure, and cannot limit the scope of the present disclosure. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure are still within the scope of the present disclosure. Those skilled in the art will easily think of embodiments of the present disclosure after considering the specification and practicing the disclosure herein. The present application is intended to cover any variations, uses or adaptive changes of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or conventional technical means in the technical field not disclosed in the present disclosure. The specification and examples are only considered as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0132] The technical features of the above embodiments can be combined in any way. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, however, as long as the combinations of the technical features do not contradict, they should be considered within the scope of the present disclosure.

[0133] Those skilled in the art readily understand that the above only describes preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for backscatter communication of a uniquely resolvable constellation pair, applied to a multi-stream coexisting backscatter communication system, characterized in that, The method comprises the following steps: reconstructing a plurality of user signals into a backscattering signal meeting a unique decomposable constellation pair characteristic of a to-be-transmitted signal of a RIS array surface; fusing the to-be-transmitted signal and the backscattering signal to obtain a fusion signal, and reflecting the fusion signal to a receiving end; decoding the receiving signal of the receiving end based on a SIC decoding rule and a unique decomposable constellation pair principle to obtain the to-be-transmitted signal; wherein, before the step of fusing the to-be-transmitted signal and the backscattering signal to obtain a fusion signal, the method further comprises the steps of: scaling the maximum constellation point energy of the backscattering signal to a preset energy value; scaling the constellation point energy of the to-be-transmitted signal based on the maximum constellation point energy of the backscattering signal; wherein, the step of decoding the receiving signal of the receiving end based on a SIC decoding rule and a unique decomposable constellation pair principle to obtain the to-be-transmitted signal comprises the steps of: decoding a fusion signal with a maximum power coefficient from the receiving signal according to a maximum ratio combining linear detection method; subtracting the decoded receiving signal and obtaining the to-be-transmitted signal one by one from the receiving signal based on a SIC decoding rule; wherein, the step of decoding a fusion signal with a maximum power coefficient from the receiving signal according to a maximum ratio combining linear detection method comprises the steps of: measuring the signal power of the receiving signal, and determining the receiving signal with a maximum power coefficient from all the receiving signals; decoding the receiving signal with a maximum power coefficient by using a decoding matrix based on the maximum ratio combining linear detection method to obtain the fusion signal; Let the channel coefficients from the source S to the RIS array, and from the RIS array to the receiver D be denoted as and respectively. If the source transmits m user signals simultaneously, then the received nth signal at the receiver is given by ； wherein, , the fusion signal is the signal to be transmitted and the backscattered signal , the signal formed by fusion forwarding, S is the total power emitted by the base station S, is the power allocation coefficient of each main system signal, is the backscattering efficiency of the RIS array, is the reflection coefficient of the RIS array, is a complex Gaussian white noise (AWGN) with power , that is ; Definitions The fusion signal with the largest power is decoded first The decoding matrix is i.e. ； wherein ; Fused signal of maximum power coefficients Detection is performed according to the following expression: ； wherein A represents the original value of the signal, represents the actual value of the signal received by the receiving end of signal A, represents the estimated value of signal A.

2. The backscatter communication method of uniquely resolvable constellation pairs of claim 1, wherein, the step of reconstructing a plurality of user signals into a backscattering signal meeting a unique decomposable constellation pair characteristic of a to-be-transmitted signal of a RIS array surface comprises the steps of: constructing a phase shift keying constellation pair according to a unique decomposable constellation pair construction method; determining the backscattering signal and the to-be-transmitted signal from the phase shift keying constellation pair.

3. The backscatter communication method of uniquely resolvable constellation pairs of claim 1, wherein, the step of subtracting the decoded receiving signal and obtaining the to-be-transmitted signal one by one from the receiving signal based on a SIC decoding rule comprises the steps of: subtracting the decoded receiving signal from the receiving signal to obtain an undecoded receiving signal; setting a decoding coefficient from the undecoded receiving signal to obtain a user decoding signal based on the maximum ratio combining linear detection method; calculating the to-be-transmitted signal one by one from the user decoding signal in a preset order.

4. The backscatter communication method of uniquely resolvable constellation pairs of claim 2, wherein, the step of constructing a phase shift keying constellation pair according to a unique decomposable constellation pair construction method comprises the steps of: constructing a phase shift keying constellation pair meeting a unique decomposable characteristic based on a phase shift keying constellation pair construction formula.

5. A backscatter communication device for a unique resolvable constellation pair for use in a multi-stream coexisting backscatter communication system, the device comprising: a plurality of backscatter communication devices, each backscatter communication device having a unique resolvable constellation pair; and a backscatter communication system configured to communicate with the plurality of backscatter communication devices using the unique resolvable constellation pairs. The device comprises: a reconstruction module configured to reconstruct a plurality of user signals into a backscattering signal meeting a unique decomposable constellation pair characteristic of a to-be-transmitted signal of a RIS array surface; a fusion module configured to fuse the to-be-transmitted signal and the backscattering signal to obtain a fusion signal, and reflect the fusion signal to a receiving end; a decoding module configured to decode the receiving signal of the receiving end based on a SIC decoding rule and a unique decomposable constellation pair principle to obtain the to-be-transmitted signal; The method further comprises, before the step of emitting the to-be-transmitted signal to the RIS array and fusing the backscattering signal to obtain a fused signal, the steps of: scaling the maximum constellation point energy of the backscattering signal to a preset energy value; scaling the constellation point energy of the to-be-transmitted signal based on the maximum constellation point energy of the backscattering signal; The step of decoding the received signal at the receiving end based on the SIC decoding rule and the principle of the uniquely decomposable constellation pair to obtain the to-be-transmitted signal comprises the steps of: decoding a fused signal with the maximum power coefficient from the received signal according to the maximum ratio combining linear detection method; subtracting the decoded received signal and sequentially obtaining the to-be-transmitted signal from the received signal based on the SIC decoding rule; The step of decoding a fused signal with the maximum power coefficient from the received signal according to the maximum ratio combining linear detection method comprises the steps of: measuring the signal power of the received signal, and determining the received signal with the maximum power coefficient from all the received signals; decoding the received signal with the maximum power coefficient by using a decoding matrix based on the maximum ratio combining linear detection method to obtain the fused signal; Let the channel coefficients from the source S to the RIS array, and from the RIS array to the receiver D be denoted as and respectively. If the source transmits m user signals simultaneously, then the received nth signal at the receiver is given by: ； wherein, , the fusion signal is the signal to be transmitted and the backscattered signal , the signal formed by fusion forwarding, P S is the total power emitted by the base station S, is the power allocation coefficient of each main system signal, is the backscattering efficiency of the RIS array, is the reflection coefficient of the RIS array, is a complex Gaussian white noise (AWGN) with power , that is ; Definitions The fusion signal with the largest power is decoded first The decoding matrix is i.e. ； wherein ; Fused signal of maximum power coefficients Detection is performed according to the following expression: ； wherein A represents the original value of the signal, represents the actual value of the signal received by the receiving end of signal A, represents the estimated value of signal A.

6. A backscatter communication device for uniquely resolvable constellation pairs, characterized by, The computer program is stored in the storage unit and is executable by the processing unit, and when the computer program is executed by the processing unit, the processing unit is caused to execute the steps of the backscattering communication method of the uniquely decomposable constellation pair according to any one of claims 1-4.

7. A storage medium, characterized by The computer program is executable by the access authentication device, and when the computer program is executed on the access authentication device, the access authentication device is caused to execute the steps of the backscattering communication method of the uniquely decomposable constellation pair according to any one of claims 1-4.

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