A power and polarity joint coding method and system for air-space-ground networks

Abstract

This invention belongs to the field of wireless communication technology and discloses a method and system for power and polarity joint coding in space-air-ground networks, mainly applicable to satellite-to-ground communication scenarios. The satellite, as the signal transmitter, forms a basic communication pair with a ground station; their communication is basic communication. The satellite also forms supplementary communication pairs with other ground stations or near-ground stations, utilizing the basic communication to achieve supplementary communication. The basic and supplementary communication pairs share channel state information; the basic communication transmitter designs a transmit precoding matrix, a power coding vector, and a polarity coding vector; the basic communication user designs a receive filter matrix to recover the basic communication data vector from the observed basic communication signal; the supplementary communication user designs a receive filter matrix to recover the supplementary communication data vector from the observed signal. This invention requires no additional communication resource consumption and can effectively improve spectrum utilization efficiency and the number of concurrent communications supported by the system.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication technology and mainly relates to a method and system for power and polarity joint coding for air-space-ground networks. It aims to increase additional communication without increasing the consumption of additional communication resources, thereby improving spectrum utilization efficiency and the number of concurrent communications supported by the system. Background Technology

[0002] In integrated air-space-ground network communication, spectrum resources are particularly scarce. Waveform design needs to achieve efficient spectrum utilization to ensure improved data transmission rates and system capacity under limited spectrum conditions. Satellite communication networks are an important component of integrated air-space-ground networks. Satellite-to-ground communication can provide coverage to remote areas and enable global data services. However, satellites are limited in terms of communication capabilities, computing power, and power. Therefore, exploring new multiplexing methods to improve spectrum resource utilization and provide data services to more users without increasing additional communication resources and hardware costs is of great significance.

[0003] Multiple access technologies are important methods for enabling multiple users to reuse communication resources. Typical examples include Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), Space Division Multiple Access (SDMA), Orthogonal Frequency Division Multiple Access (OFDMA), and Non-Orthogonal Multiple Access (NOMA). Among these, FDMA, TDMA, CDMA, SDMA, and OFDMA are all based on the principle of "orthogonality," effectively avoiding mutual interference between concurrent user communications by allocating different frequency bands, time slots, codewords, and spatial or time-frequency resource blocks to different users. However, while these orthogonal multiple access methods ensure conflict-free resource allocation, they also limit the number of concurrent users the network can support to some extent. In contrast, NOMA allows multiple users to communicate in parallel on the same time and frequency resources, thus significantly improving spectral efficiency (SE). In Power-Domain NOMA (PD-NOMA), the transmitter allocates different transmit powers to different users based on their channel gain differences. The user end uses signal detection algorithms to separate and decode their respective information from the superimposed signals. In Code-Domain NOMA (CD-NOMA), a typical example is Sparse Code Multiple Access (SCMA). This technology maps user data to sparse codewords constructed based on a multi-dimensional constellation, allowing multiple users' codewords to be superimposed and transmitted non-orthogonally on the same time-frequency resources. The receiver uses a Message Passing Algorithm (MPA) for signal detection, thereby effectively improving system spectrum utilization and user access capabilities.

[0004] Furthermore, interference management among multi-user communications is a key technical issue when reusing communication resources. Effective interference management can further improve the performance of communication systems. In related research, utilizing interference to improve communication is a novel approach. Interference Recycling (IRC) utilizes the interaction between wireless signals to construct a regenerated interference signal, transforming harmful interference into a useful signal carrying desired data information, thereby enhancing the transmission of desired data through interference.

[0005] However, traditional orthogonal multiple access (OMA) technologies have significant limitations in spectrum resource utilization efficiency, making it difficult to support the access needs of a large number of concurrent users. Non-orthogonal multiple access (NOA) technologies face problems such as error propagation, user privacy leakage risks, and high signal processing complexity of receiving equipment. In addition, interference management methods based on signal-to-signal interactions require additional configuration of transmitting equipment to generate and transmit regenerated signals, resulting in additional transmit power overhead.

[0006] In summary, existing multiplexing methods suffer from the following problems: First, traditional orthogonal multiple access methods (such as FDMA, TDMA, CDMA, SDMA, and OFDMA) limit the number of concurrent users supported by the system due to resource exclusivity. Second, non-orthogonal multiple access technologies (such as PD-NOMA and CD-NOMA), while improving spectral efficiency, suffer from problems such as error propagation, privacy leakage risks, and high computational complexity. Third, interference-based methods (such as IRC) require additional communication equipment and transmit power, leading to a significant increase in system hardware overhead. Therefore, exploring new multiplexing methods to improve spectral efficiency has significant research significance and practical value. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a power and polarity joint coding method and system for air-space-ground networks, aiming to solve the problems of limited number of concurrent communication users supported by existing multiplexing methods, error propagation, privacy leakage, high complexity, and the need for additional equipment and power resources.

[0008] This invention discloses a power and polarity joint coding method for space-air-ground networks, applicable to satellite-to-ground communication scenarios. In this integrated space-air-ground network, the satellite acts as a signal transmitter, forming a basic communication pair with a ground station. Their communication is basic communication, with the satellite as the basic communication transmitter and the ground station as the basic communication user. Furthermore, the satellite can simultaneously establish auxiliary communication with other ground or near-ground stations, which is based on the basic communication. The communication pair formed by the satellite and other ground or near-ground stations is called an additional communication pair, and the other ground or near-ground stations are called additional communication users. The power and polarity joint coding method for space-air-ground networks includes: the basic communication transmitter designing a transmission precoding matrix based on the channel between itself and the basic communication users; subsequently, the basic communication transmitter designing a power coding vector and a polarity coding vector based on the channel between itself and the additional communication users, the transmission precoding matrix, the basic communication data vector, and the additional communication data vector; and finally, the additional communication user designing a receive filtering matrix based on the channel between itself and the basic communication transmitter, receiving a mixed signal composed of the basic communication signal, and then demodulating the additional communication data sent to it by the basic communication transmitter from the mixed signal.

[0009] Furthermore, the specific steps of the power and polarity joint coding method for space-air-ground networks are as follows: Step 1: The basic communication user directly detects the signal transmitted by the basic communication transmitter to obtain the data information sent to them by the basic communication transmitter. The basic communication user estimates the channel state information between themselves and the basic communication transmitter. Basic communication users according to The signal transmitted by the basic communication transmitter is detected. Additional communication users estimate the channel state information between themselves and the basic communication transmitter. and the estimated Feedback is sent to the basic communication transmitter; Step 2, the basic communication transmitter determines the channel state information. Design the transmission precoding matrix It is used to send basic communication signals to basic communication users. The basic communication transmitter transmits signals according to the transmission precode. Channel state information between it and additional communication users Basic communication data and additional communication data Design power encoding vector and polarity encoding vector The basic communication transmitter comprehensively utilizes the transmission precoding matrix. Power encoding vector and polarity encoding vector Basic communication data Preprocessing is performed, and then the data is fed to the transmit antenna of the basic communication transmitter for transmission. This is followed by power-coded vector processing. and polarity encoding vector The basic communication signal can be superimposed at the additional communication user to carry additional communication data. The expected signal; Step 3, basic communication users, based on channel state information Design the receiver filtering matrix. Used to detect the basic communication data carried in the basic communication signals transmitted by the basic communication transmitter. Considering that polarity coding vectors may alter the polarity of the underlying communication signal, affecting the accuracy of the underlying communication user's detection of the underlying communication signal, this invention can employ out-of-band or in-band signaling to transmit polarity coding information to the underlying communication user, ensuring that the underlying communication user can accurately recover the underlying communication data from the underlying communication signal after power and polarity coding. ; Step 4, the additional communication user adds information based on channel state information. Design the receiver filtering matrix. It is used to recover additional communication data from the signal obtained by superimposing the basic communication signals transmitted by the basic communication transmitter, which it observes. .

[0010] The core design concept of this invention lies in enabling the superposition of a mixed signal carrying additional communication data at the additional communication user by jointly encoding the power and polarity of the basic communication signal. This invention achieves data transmission between the basic communication transmitter and the additional communication user without introducing additional equipment or consuming power resources, effectively improving spectrum utilization and the system's ability to provide multi-user data transmission.

[0011] Compared with the prior art, the present invention has the following advantages: 1. Compared with traditional orthogonal multiple access technology, this invention can generate additional communication using basic communication signals, significantly improving the utilization efficiency of spectrum resources, while increasing the number of concurrent communications that the system can support, meeting the needs of high-density access scenarios.

[0012] 2. Compared to non-orthogonal multiple access (NOA) technologies, this invention only requires calculating the power coding vector and polarity coding vector of the basic communication signal and making simple adjustments to the basic communication signal to achieve communication between the basic communication transmitter and the auxiliary communication user. This invention has low computational complexity, and because the characteristics of the basic communication signal are adjusted through joint coding, the auxiliary communication user cannot know the data information carried by the basic communication signal, thus avoiding the risk of user privacy leakage.

[0013] 3. Compared with interference exploitation methods, this invention does not require additional communication resources such as transmitters and power. It can synthesize signals carrying additional communication data at additional communication users simply by adjusting the power and polarity of existing basic communication signals, thereby reducing system deployment and operation costs.

[0014] 4. This invention is applicable not only to simple communication scenarios with only one basic communication pair and one additional communication pair, but also to complex network environments where multiple basic communication pairs and multiple additional communication pairs coexist. In such cases, this invention can generate multiple additional communications, thereby further improving network spectrum utilization efficiency and the number of concurrent communication users supported. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating a power and polarity joint coding method for air-space-ground networks provided by the present invention. Figure 2 This is a schematic diagram of a wireless communication system model for a power and polarity joint coding method for air-space-ground networks provided by the present invention. Figure 3 This invention provides a power and polarity coding method for space-air-ground networks (P...). 2 C-MUX) and Zero-Forcing Beamforming (ZFBF) and Non-Power and Polarity Coding (non-P) 2 Simulation comparison of the average spectral efficiency of the system at time C). Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the present invention clearer, the following detailed description of the present invention is provided in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0017] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0018] Example 1 With the deployment of fifth-generation (5G) mobile networks, the development of sixth-generation (6G) wireless technology has ushered in a significant transformation. 6G promises to revolutionize wireless communication by providing seamless connectivity, global broadband coverage, and extensive computing services. To achieve these goals, a comprehensive three-dimensional network integrating space, air, and ground components, including satellites, airborne platforms, and ground nodes, is widely considered a fundamental component of the upcoming 6G infrastructure. However, current satellite systems are limited by factors such as the weight, size, and transmission power of individual satellites. Therefore, exploring novel multiplexing methods to improve spectrum resource utilization and provide data services to more users without adding extra communication resources and physical components has significant research implications and practical value.

[0019] To address this problem, this invention proposes a power and polarity joint coding method for space-air-ground networks, applicable to satellite and terrestrial communication scenarios. See also... Figure 2 In this integrated air-space-ground network, the satellite acts as a signal transmitter, forming a basic communication pair with the ground station. Their communication is basic communication, with the satellite serving as the basic communication transmitter, referred to as Alice, and the ground station as the basic communication user, referred to as Bob. Furthermore, the satellite can simultaneously establish auxiliary communication with other ground stations or near-ground stations, which utilizes the basic communication. The communication pair formed by the satellite and other ground stations or near-ground stations is called an additional communication pair, and the other ground stations or near-ground stations are called additional communication users, referred to as Carol. The channel matrix between Alice and Bob is as follows: The channel matrix between Alice and Carol is Alice expects to send a basic communication data vector to Bob. The expectation is to send additional communication data vectors to Carol. This invention performs joint encoding of the power and polarity of the basic communication signal, enabling the basic communication signal to be superimposed at the Carol position with a signal carrying... Mixed signals, see Figure 1 It includes the following steps: (1) The basic communication pair and the supplementary communication pair share channel state information: (1a) The basic communication user estimates the channel state information between itself and the basic communication transmitter. The estimated channel state information is then fed back to the basic communication transmitter.

[0020] (1b) Additional communication users estimate channel state information between themselves and the underlying communication transmitter. The estimated channel state information is then fed back to the basic communication transmitter.

[0021] (2) Design of basic communication transmitter: transmission precoding matrix, power coding vector and polarity coding vector; (3) The basic communication user designs the receiving filter matrix to recover the basic communication data vector from the basic communication signal it observes: (3a) Basic communication users based on channel Design the receiver filtering matrix. ,use The observed signals are processed.

[0022] (3b) Basic communication user use After filtering, the estimated signal is ,in , , , , , The number of basic communication signals.

[0023] (3c) Basic communication users eliminate the polarity coding vector based on the polarity coding information. After the impact, the basic communication data vector can be recovered. .

[0024] (4) Additional communication users design a receiving filter matrix to recover the additional communication data vector from the signals they observe.

[0025] (4a) Additional communication users based on channel Design a receiver matrix and use The observed signals are processed.

[0026] (4b) Additional communication user use After processing the observed signal, the estimated signal is: .

[0027] (4c) Under the influence of the power coding vector and the polarity coding vector, the additional communication user estimates are obtained as follows: Additional communication signals for the road must meet the following requirements. ,in , , , This represents the number of additional communication signals. The additional communication user can then recover the additional communication data vector from the observed signals. .

[0028] Example 2 A power and polarity joint coding method for air-space-ground networks is the same as in Embodiment 1. In step (2), the basic communication transmitter designs the power coding vector and polarity coding vector based on the transmission precoding matrix, the channel state information between the transmitter and the additional communication users, the basic communication data vector, and the additional communication data vector. The method includes the following steps: (2a) The signal received by the additional communication user from the basic communication transmitter can be represented as follows: ,in This indicates the transmit power of the basic communication transmitter. , , , , Indicates the number of basic communication signals. This represents additive white Gaussian noise.

[0029] (2b) Additional communication users use a filtering matrix right Processing is performed to recover the signal from the superposition of the basic communication signals. Additional communication users use a receive filtering matrix to observe the signal obtained by superimposing the basic communication signals. Processing can yield ,in , , , Indicates the number of additional communication signals.

[0030] (2c) For by Equations Solving the system of equations yields the power encoding vector. and polarity encoding vector The value of .

[0031] The basic communication transmitter of this invention is based on the transmission precoding matrix. Channel state information between it and additional communication users Basic communication data vector and additional communication data vectors Design power encoding vector and polarity encoding vector After power encoding vector and polarity encoding vector The basic communication signal can be superimposed at the additional communication user to generate a vector carrying additional communication data. The expected signal.

[0032] When both the basic communication pair and the supplementary communication pair are a pair, steps (1) to (4) can be followed directly to enable the supplementary communication user to recover its desired supplementary communication data vector from the observed signal. When there are multiple basic communication pairs and / or additional communication pairs, each basic communication transmitter needs to cooperate with each other to design its own power coding vector according to steps (1) to (4). and polarity encoding vector This allows each additional communication user to still recover the desired additional communication data vector from the mixed signal they observe. .

[0033] Example 3 A power and polarity joint coding method for air-space-ground networks is the same as in Examples 1-2. (Refer to...) Figure 2 This invention uses an integrated air-space-ground network as a system model. The system includes three wireless communication devices: a satellite as the signal transmitter, forming a basic communication pair with a ground station; the satellite as the basic communication transmitter; and the ground station as the basic communication user. Furthermore, the satellite can simultaneously establish auxiliary communications with other ground stations or near-ground stations, which are implemented using the basic communication. The communication pair formed by the satellite and other ground stations or near-ground stations is called an additional communication pair, and the other ground stations or near-ground stations are called additional communication users.

[0034] Reference Figure 1 The implementation steps of this invention are as follows: Step 1: The basic communication pair and the supplementary communication pair share channel state information.

[0035] (1a) The basic communication user estimates the channel state information between itself and the basic communication transmitter. The estimated channel state information is then fed back to the basic communication transmitter.

[0036] (1b) Additional communication users estimate channel state information between themselves and the underlying communication transmitter. The estimated channel state information is then fed back to the basic communication transmitter.

[0037] Step 2: Design the basic communication transmitter, including the transmission precoding matrix, power coding vector, and polarity coding vector.

[0038] (2a) The signal received by the additional communication user from the basic communication transmitter can be represented as follows: ,in This indicates the transmit power of the basic communication transmitter. , , , , Indicates the number of basic communication signals. This represents additive white Gaussian noise.

[0039] (2b) Additional communication users use a filtering matrix right Processing is performed to recover the signal from the superposition of the basic communication signals. Additional communication users use a receive filtering matrix to observe the signal obtained by superimposing the basic communication signals. Processing can yield ,in , , , Indicates the number of additional communication signals.

[0040] (2c) For by Equations , Solving the system of equations yields the power encoding vector. and polarity encoding vector The value of .

[0041] Step 3: The basic communication user designs the receiving filter matrix to recover the basic communication data vector from the basic communication signal it observes.

[0042] (3a) Basic communication users based on channel Design the receiver filtering matrix. ,use The observed signals are processed.

[0043] (3b) Basic communication user use After filtering, the estimated signal is ,in , , , , , The number of basic communication signals.

[0044] (3c) Basic communication users eliminate the polarity coding vector based on the polarity coding information. After the impact, the basic communication data vector can be recovered. .

[0045] Step 4: The additional communication user designs the receive filter matrix to recover the additional communication data vector from the signal it observes.

[0046] (4a) Additional communication users based on channel Design a receiver matrix ,use The observed signals are processed.

[0047] (4b) Additional communication user use After filtering, the estimated signal is: .

[0048] (4c) Under the influence of the power coding vector and the polarity coding vector, the additional communication user estimates are obtained as follows: Road signal satisfies ,in ,in , , This represents the number of additional communication signals. The additional communication user can then recover the additional communication data vector from the observed signals. .

[0049] This invention, through the design of power coding factors and polarity coding factors, enables data transmission between the basic communication transmitter and additional communication users without introducing additional communication resources, effectively improving the network's spectrum utilization and ability to serve multiple users.

[0050] The application effects of this invention are further illustrated by the following simulation experiments.

[0051] Example 4 A power and polarity joint coding method for air-space-ground networks is the same as in Examples 1-3.

[0052] I. Simulation Conditions Alice and Bob are each equipped with two antennas, while Carol is equipped with one antenna. Alice's transmission power is... ,definition The normalized value for noise power is dB, and set dB. For simplicity, both the basic communication pair and the additional communication pair involved in the simulation use QPSK modulation.

[0053] II. Simulation Content Forced beamforming (ZFBF) and non-power and polarity co-coding (nonP) will be implemented. 2 C) and the present invention (P) 2 C-MUX) is used for performance simulation and comparison in the above communication scenarios. For ZFBF, Alice transmits data to Bob and Carol respectively via one channel. For nonP 2 C. Alice sends two data streams to Bob using spatial multiplexing, but this fails to provide additional communication for Carol; therefore, nonP is not supported in the simulation. 2The system spectral efficiency (SE) of C is Bob's SE. Using ZFBF and nonP... 2 At time C, Alice allocates the same transmit power to both data transmission paths. The result is as follows: Figure 3 As shown.

[0054] from Figure 3 As can be seen from this, the proposed solution P of this invention 2 System C has the best SE performance, nonP 2 C is next, ZFBF and nonP 2 C's performance is similar. This is because P's performance is similar. 2 C-MUX can provide Carol with an additional data communication service using two basic communication signals. Meanwhile, nonP... 2 C can only provide Bob with two basic communication data services, while ZFBF provides Bob and Carol with one basic communication data service and one additional communication data service respectively. Both methods only support two concurrent communication channels. Therefore, P 2 C-MUX can achieve a higher system SE.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A power and polarity joint coding method for air-space-ground networks, applicable to satellite-to-ground communication scenarios. In the integrated air-space-ground network, the satellite acts as a signal transmitter, forming a basic communication pair with a ground station. The communication between the satellite and the ground station is basic communication, wherein the satellite is the basic communication transmitter and the ground station is the basic communication user. The satellite can simultaneously establish auxiliary communication with other ground stations or near-ground stations. The communication pair formed by the satellite and other ground stations or near-ground stations is called an additional communication pair, and the other ground stations or near-ground stations are called additional communication users. The method is characterized in that... Includes the following steps: (1) Basic communication users estimate the channel state information between themselves and the basic communication transmitter. Basic communication users according to Detects the basic communication signals transmitted by the basic communication transmitter; additional communication users estimate the channel state information between themselves and the basic communication transmitter. and the estimated Feedback is sent to the basic communication transmitter; (2) The basic communication transmitter transmits according to the precoding matrix. Channel state information Basic communication data vector and additional communication data vectors Confirm its own power encoding vector and polarity encoding vector The basic communication transmitter uses a transmission precoding matrix. Power encoding vector and polarity encoding vector The basic communication data vector carried in the basic communication signal Preprocessing is performed, and the preprocessed basic communication signal is fed to the transmitting antenna of the basic communication transmitter for transmission; the preprocessed basic communication signal is superimposed with an additional communication data vector at the additional communication user. The desired signal; the transmit precoding matrix The basic communication transmitter uses channel state information A precoding matrix designed for transmitting basic communication signals to basic communication users, the basic communication data vector It is a vector of basic communication data carried by the basic communication signal; (3) Basic communication users, based on channel state information Determine the receive filter matrix It is used to detect the basic communication data vector carried in the preprocessed basic communication signal transmitted by the basic communication transmitter. The basic communication transmitter uses out-of-band or in-band signaling to transmit the polarity-coded vector to the basic communication user, ensuring that the user can recover the basic communication data vector from the preprocessed basic communication signal. ; (4) Additional communication users based on channel state information Determine the receive filter matrix It is used to recover the additional communication data vector from the desired signal obtained by superimposing the preprocessed basic communication signals transmitted by the basic communication transmitter. .

2. The power and polarity joint coding method for space-air-ground networks according to claim 1, characterized in that, Step (2) also includes: (2a) The additional communication user receives a preprocessed basic communication signal from the basic communication transmitter, the basic communication signal being represented as follows: ,in, This represents the transmit power of the basic communication transmitter and the transmit precoding matrix. Basic communication data vector Power encoding vector Polarity encoding vector , Indicates the number of basic communication signals. This represents additive white Gaussian noise. Indicates the first N Road infrastructure communication data; (2b) Additional communication users use a filtering matrix right Processing is performed to obtain ,in, , , , The filter matrix represents the number of additional communication signals. The filter matrix The conjugate transpose of . For the first Additional communication data; (2c) Basic communication transmitter to the Equations , Solving the system of equations yields the power encoding vector. and polarity encoding vector The value of , where Indicates the first Additional communication data.

3. A communication system that applies the power and polarity joint coding method for air-space-ground networks as described in any one of claims 1 to 2.

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