Satellite-ground integration network communication method and satellite-ground integration network
By dividing user services into ultra-public information, satellite public information, and satellite private information in the satellite-ground converged network, and transmitting them through shared and dedicated frequency bands, combined with beamforming parameter optimization, the problems of cross-network interference and user fairness under spectrum sharing conditions are solved, thereby improving the robustness and throughput of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING UNIV OF POSTS & TELECOMM
- Filing Date
- 2026-03-11
- Publication Date
- 2026-07-24
AI Technical Summary
In satellite-ground converged networks, there are serious problems of cross-network interference and insufficient user fairness under spectrum sharing conditions. In particular, when channel state information is inaccurate, existing technologies are difficult to effectively coordinate interference and ensure system throughput and user fairness.
Multi-beam satellites are used to decompose user services into ultra-public information, satellite public information, and satellite private information, which are transmitted through shared and dedicated frequency bands. Ground base stations decompose services into cellular public information and cellular private information, which are transmitted through shared frequency bands. Auxiliary variables are introduced to transform the joint optimization problem into a non-convex optimization problem. Beamforming parameters are obtained through iterative solutions, achieving interference coordination and resource optimization.
Without increasing additional spectrum overhead, it significantly enhances the robustness, throughput, and user experience consistency of the space-ground converged network under non-ideal channel conditions, and improves spectrum efficiency and communication quality for edge users.
Smart Images
Figure CN122458031A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of wireless communication technology, and in particular to a satellite-ground converged network communication method and a satellite-ground converged network. Background Technology
[0002] With the continuous growth of global communication demands and the expansion of application scenarios, the 6th Generation Mobile Communication Technology (6G) is evolving towards full coverage, high reliability and low latency, and intelligent convergence. As a key enabling architecture for 6G, the space-ground converged network effectively overcomes geographical limitations by deeply integrating high-Earth orbit, medium-Earth orbit, or low-Earth orbit satellite communication systems with terrestrial cellular networks. This enables seamless coverage in remote areas such as oceans, deserts, and mountains, and supports diverse services such as emergency communication, wide-area IoT access, and aerial platform interconnection. This integrated space-ground communication paradigm not only expands the service boundaries of traditional terrestrial networks but also provides the technological foundation for building a globally unified communication infrastructure, thus becoming an indispensable and important component of the future communication system.
[0003] Currently, satellite-terrestrial converged networks primarily employ spectrum sharing or hybrid spectrum access mechanisms to alleviate the increasingly strained spectrum resources. In these schemes, satellite systems and terrestrial cellular systems operate collaboratively in the same or adjacent frequency bands, improving overall spectrum efficiency through dynamic spectrum allocation, power control, or interference coordination strategies. However, due to the wide coverage of satellite beams, sparse user distribution, and complex channel environment, coupled with the concurrent transmission of multiple users resulting from the dense deployment of terrestrial base stations, the system faces severe cross-network co-channel interference, such as downlink interference from satellites to terrestrial users, uplink interference from terrestrial terminals to satellite reception, and co-channel interference between multiple beams within the satellite. More critically, in actual deployments, Channel State Information (CSI) is often difficult to obtain accurately, leading to a decline in the performance of interference suppression algorithms, which in turn causes problems such as system throughput fluctuations, deterioration of service quality for edge users, and imbalances in fairness among users.
[0004] In summary, how to effectively coordinate cross-network and intra-system interference in a space-ground integrated network under spectrum sharing conditions, and how to ensure user fairness and system throughput in scenarios with inaccurate channel state information, have become urgent technical problems to be solved. Summary of the Invention
[0005] This application provides a satellite-ground converged network communication method and a satellite-ground converged network to solve the defects of existing satellite-ground converged networks in spectrum sharing environments, such as difficulty in interference management, low resource utilization efficiency, and insufficient user fairness.
[0006] This application provides a satellite-ground integrated network communication method, including the following steps: Multi-beam satellites break down all user services into super-public information, satellite public information, and satellite private information. The super-public information is globally shared data generated by jointly processing multicast service information carried by all beams, used to coordinate cross-network interference. The satellite public information is the common portion of user information in each beam, used to coordinate multi-user interference within the satellite system. The satellite private information is the private portion of user information in each beam, used to carry personalized user service data. The multi-beam satellite transmits the super-public information through a shared frequency band, and transmits the satellite public information and the satellite private information through a dedicated frequency band; wherein, the shared frequency band is a spectrum resource shared by the satellite system and the ground cellular system, and the dedicated frequency band is a spectrum resource used independently by the satellite system; The terrestrial base station divides local user services into cellular public information and cellular private information; wherein, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user; The ground base station transmits the cellular public information and the cellular private information through the shared frequency band.
[0007] According to the satellite-ground integrated network communication method provided in this application, the satellite-ground integrated network communication method further includes: The satellite terminal receives and decodes the super-public information via the shared frequency band. After receiving satellite signals through the dedicated frequency band, the satellite terminal decodes the satellite signals in the order of satellite public information and satellite private information.
[0008] According to the satellite-ground integrated network communication method provided in this application, the satellite-ground integrated network communication method further includes: After receiving cellular signals through the shared frequency band, the cellular terminal decodes the cellular signals in the order of super public information, cellular public information, and cellular private information.
[0009] According to the satellite-ground integrated network communication method provided in this application, the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station are determined based on the following steps: A joint optimization problem is constructed with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal. Solving the joint optimization problem yields the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0010] According to the satellite-ground integrated network communication method provided in this application, solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0011] This application provides a space-ground integrated network, including: The satellite system includes multiple multi-beam satellites. Each multi-beam satellite is used to decompose all user services into super-public information, satellite public information, and satellite private information. The super-public information is transmitted through a shared frequency band, while the satellite public information and the satellite private information are transmitted through a dedicated frequency band. The super-public information is globally shared data generated by jointly processing multicast service information carried by all beams, used to coordinate cross-network interference. The satellite public information is the common part of user information in each beam, used to coordinate multi-user interference within the satellite system. The satellite private information is the private part of user information in each beam, used to carry personalized user service data. The shared frequency band is a spectrum resource shared by the satellite system and the terrestrial cellular system, while the dedicated frequency band is a spectrum resource used independently by the satellite system. A terrestrial cellular system includes multiple terrestrial base stations, each of which is used to split local user services into cellular public information and cellular private information, and transmit the cellular public information and the cellular private information through the shared frequency band; wherein, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user.
[0012] According to the satellite-ground integrated network provided in this application, the satellite system further includes a satellite terminal, which is used to receive and decode the super-public information through the shared frequency band, and to receive the satellite public information and the satellite private information through the dedicated frequency band, and then decode them in the order of satellite public information and satellite private information.
[0013] According to a satellite-ground integrated network provided in this application, the ground cellular system further includes a cellular terminal, which is used to receive the super-public information, the cellular public information and the cellular private information through the shared frequency band, and then decode them in the order of super-public information, cellular public information and cellular private information.
[0014] According to the satellite-to-ground fusion network provided in this application, the satellite-to-ground fusion network further includes: A gateway is used to construct a joint optimization problem with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal; the joint optimization problem is solved to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0015] According to a satellite-ground integrated network provided in this application, solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0016] The satellite-ground integrated network communication method and network provided in this application divide user services into three layers: super-public information, satellite public information, and satellite private information. Super-public information, as a global coordination signal, carries the joint processing results of multicast services from all beams and is broadcast via a shared frequency band, allowing the ground system to detect and cancel cross-network interference from the satellite system in advance. Satellite public information is used to coordinate interference among multiple users within the same beam, while satellite private information carries personalized data. Both are transmitted via dedicated frequency bands to avoid additional conflicts with the ground system. Simultaneously, the ground base station also divides its services into cellular public information and cellular private information, transmitting them uniformly on a shared frequency band. Cellular public information can be jointly decoded by some users, helping to improve multi-user diversity gain and assisting in interference cancellation. This design approach offers several advantages. First, the explicit transmission of public information in the shared frequency band provides a priori interference structure for the ground receiver. Even under conditions of inaccurate CSI, cross-network interference between satellite and ground can be effectively suppressed through interference decoding or Successive Interference Cancellation (SIC) techniques. Second, moving sensitive private information to a dedicated frequency band fundamentally avoids uncontrollable interference caused by spectrum reuse, ensuring the reliability and privacy of user data. Furthermore, the separation of public and private information allows the system to dynamically adjust power and coding strategies based on service priorities and user distribution, significantly improving communication quality and system fairness for edge users while enhancing overall spectrum efficiency. In summary, this application significantly enhances the robustness, throughput, and user experience consistency of the satellite-ground converged network under non-ideal channel conditions without increasing additional spectrum overhead. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a flowchart illustrating the satellite-ground integrated network communication method provided in this application; Figure 2 This is a comparative diagram of the maximum and minimum fairness rates at different heights provided in this application; Figure 3 This is a comparative diagram of the maximum and minimum fairness rates under different transmit powers provided in this application; Figure 4This is a comparative diagram of the maximum and minimum fairness rates under different numbers of cellular terminals provided in this application; Figure 5 This is a comparative diagram of the maximum and minimum fairness rates under different numbers of satellite beams provided in this application; Figure 6 This is a schematic diagram of the structure of the satellite-ground fusion network provided in this application. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0020] It should be noted that in the description of the embodiments of this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. The terms "upper," "lower," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, they can be fixed connections, detachable connections, or integral connections; they can be mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; and they can be internal connections between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0021] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, without limiting the number of objects; for example, a first object can be one or more. Furthermore, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects have an "or" relationship.
[0022] The following is combined with Figures 1-6 This application describes the satellite-ground fusion network communication method and satellite-ground fusion network provided in the embodiments of this application.
[0023] Figure 1 This is a flowchart illustrating the satellite-ground integrated network communication method provided in this application, as shown below. Figure 1 As shown, the method includes the following: S110, a multi-beam satellite, divides all user services into ultra-public information, satellite public information, and satellite private information; S120, the multi-beam satellite transmits the super-public information through a shared frequency band, and transmits the satellite public information and the satellite private information through a dedicated frequency band; S210, the ground base station splits local user services into cellular public information and cellular private information; S220, the ground base station transmits the cellular public information and the cellular private information through the shared frequency band.
[0024] In this application embodiment, the satellite-ground converged network refers to a heterogeneous communication architecture that deeply integrates satellite communication systems and terrestrial cellular mobile communication systems, aiming to achieve seamless global coverage, highly reliable connectivity, and diversified service support.
[0025] In this embodiment of the application, S110 and S120 are multi-beam satellite-side processes, and the executing entity is the multi-beam satellite; S210 and S220 are ground base station-side processes, and the executing entity is the ground base station.
[0026] In S110, a multi-beam satellite refers to a communication satellite with multiple independent or partially overlapping coverage areas (beams). Each beam can serve a group of ground users, and system capacity is improved through frequency reuse and beamforming. The super-public information is globally shared data generated by jointly processing the multicast service information carried by all beams, used to coordinate cross-network interference; the satellite public information is the common part of user information in each beam, used to coordinate multi-user interference within the satellite system; the satellite private information is the private part of user information in each beam, used to carry personalized user service data.
[0027] Here, multi-beam satellites decompose all user services they serve into three layers: Super-public information: Multicast services (such as system broadcast and multicast video) across all beams are jointly encoded or aggregated to generate a globally consistent coordination signal; Satellite public information: For each beam, information common to users within that beam is extracted, merged by beam or across the entire network, and jointly encoded into a satellite public data stream, such as the public control channel or the public layer in Non-Orthogonal Multiple Access (NOMA); Satellite private information: The satellite private information corresponding to each beam is encoded into independent private data streams.
[0028] In S120, the shared frequency band is the spectrum resource used jointly by the satellite system and the ground cellular system, while the dedicated frequency band is the spectrum resource used independently by the satellite system.
[0029] Here, public information is broadcast via a shared frequency band, meaning all beams transmit synchronously or quasi-synchronously for decoding by all satellite and cellular terminals. Public and private satellite information is transmitted via dedicated frequency bands for decoding by the corresponding satellite terminals. In practice, beam isolation and time-frequency resource allocation can be used to differentiate between different users.
[0030] Preferably, the broadcast of extra-public information employs highly robust modulation and coding to ensure reliable decoding at the ground receiver even under low signal-to-noise ratio conditions.
[0031] In S210, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user.
[0032] Here, the ground base station breaks down the cellular user services it serves into two parts: cellular public information, where all public content for multiple users, such as system broadcast messages and multicast video clips, is uniformly aggregated and jointly encoded into a single cellular public data stream. This data stream uses a highly robust modulation and coding scheme to ensure that all target users within the coverage area can successfully decode it; and cellular private information, where each user's exclusive service data, such as personal voice messages and private files, is independently encoded into a corresponding cellular private data stream, which can adopt an adaptive modulation and coding strategy adapted to the channel conditions of each user.
[0033] In S220, the aforementioned public data stream and multiple private data streams are combined into a composite signal within the same time-frequency resource block through non-orthogonal superposition in the power domain, and then transmitted via a shared frequency band. Specifically, the cellular public data stream is transmitted at a higher transmit power, while each cellular private data stream is transmitted at a relatively lower and differentiated power, typically allocated according to the user channel gain, with lower power for near-end users. The receiver utilizes serial interference cancellation technology to first decode the strong signal (public stream or near-end private stream), and then eliminates interference step by step to recover the weak signal. Understandably, the structure and content of cellular public data streams transmitted by the ground side in shared frequency bands are transparent or predictable to the satellite system. This allows the satellite to attempt to decode the public stream during uplink reception or interference monitoring to suppress cross-network interference from the ground. Simultaneously, the extra-public information broadcast by the satellite in shared frequency bands provides ground users with prior knowledge of external interference, enabling them to not only eliminate intracellular interference during SIC (Self-Installation Interference) but also partially offset co-channel interference from satellite downlink signals.
[0034] It should be noted that the satellite-side process and the ground base station-side process are two different processes, and there is no strict time limit between them.
[0035] The satellite-ground integrated network communication method provided in this application divides user services into three layers: super-public information, satellite public information, and satellite private information. Super-public information serves as a global coordination signal, carrying the joint processing results of multicast services from all beams. It is broadcast through a shared frequency band, allowing the ground system to detect and cancel cross-network interference from the satellite system in advance. Satellite public information coordinates interference among multiple users within the same beam, while satellite private information carries personalized data. Both are transmitted through dedicated frequency bands to avoid additional conflicts with the ground system. Simultaneously, the ground base station also splits its services into cellular public information and cellular private information, transmitting them uniformly on a shared frequency band. Cellular public information can be jointly decoded by some users, helping to improve multi-user diversity gain and assist in interference cancellation. This design approach offers several advantages. First, the explicit transmission of public information in the shared frequency band provides a priori interference structure for the ground receiver. Even under conditions of inaccurate CSI, cross-network interference between satellite and ground can be effectively suppressed through interference decoding or serial interference cancellation techniques. Second, moving sensitive private information to a dedicated frequency band fundamentally avoids uncontrollable interference caused by spectrum reuse, ensuring the reliability and privacy of user data. Furthermore, the separation of public and private information allows the system to dynamically adjust power and coding strategies based on service priorities and user distribution, significantly improving communication quality and system fairness for edge users while enhancing overall spectrum efficiency. In summary, this application significantly enhances the robustness, throughput, and user experience consistency of the satellite-ground converged network under non-ideal channel conditions without increasing additional spectrum overhead.
[0036] In an optional embodiment, the satellite-ground fusion network communication method further includes: The satellite terminal receives and decodes the super-public information via the shared frequency band. After receiving satellite signals through the dedicated frequency band, the satellite terminal decodes the satellite signals in the order of satellite public information and satellite private information.
[0037] Here, a satellite terminal refers to user equipment deployed on the ground, in the air, or at sea for accessing a satellite communication system, such as portable satellite phones, vehicle / airborne communication terminals, and IoT sensor nodes. In this embodiment, it specifically refers to a downlink user terminal served by a multi-beam satellite. Decoding order refers to the logical order in which the receiver decodes each information component according to a specific priority when processing superimposed or multi-layered signals.
[0038] In practice, satellite terminals receive superpublic information broadcast from multi-beam satellites on a shared frequency band via their radio frequency front-end. This signal may be superimposed with downlink signals from terrestrial cellular systems, i.e., cellular public information and cellular private information, creating a complex interference environment. Because the superpublic information is a globally broadcast, highly robustly coded, and high-power signal, even with terrestrial interference, the terminal can still successfully decode it using a strong signal-to-interference-plus-noise ratio (SNR). The decoded superpublic information contains cross-network interference coordination parameters, such as the scheduling sequence of each satellite beam, transmission power profile, and multicast content identifiers, which are used to assist in interference coordination.
[0039] Here, the satellite terminal receives a composite signal from its assigned satellite beam on a dedicated frequency band. This signal contains satellite public information, i.e., shared data for multiple users within the beam, and satellite private information, i.e., personalized data specific to the satellite terminal. The satellite terminal first decodes the satellite public information. If decoding is successful, it reconstructs the satellite public signal from the received satellite signal and subtracts the satellite public signal component to achieve interference cancellation. After removing the satellite public information, the remaining signal mainly contains satellite private information and noise. The satellite terminal uses a demodulation method adapted to its channel conditions to recover the private service data.
[0040] It is understandable that shared and dedicated frequency bands use different frequency bands, and hardware can process them in parallel through dual radio frequency links, so the reception of shared and dedicated frequency bands can be carried out asynchronously; however, the decoding within the dedicated frequency band must be strictly in sequence, that is, the decoding and cancellation of satellite public information must be completed first before satellite private information can be reliably decoded. If the order is reversed, satellite private information will be severely interfered with by satellite public information, resulting in a surge in the bit error rate.
[0041] The satellite-ground integrated network communication method provided in this application embodiment has super-public information in the shared frequency band, undertaking cross-system coordination, while only internal interference of the satellite system exists in the dedicated frequency band, making the interference source controllable and the structure known; furthermore, for the signals of the dedicated channel, the interference of the public layer is eliminated by first decoding the public information and then decoding the private information, so that the private information is decoded in a clean channel, which significantly improves the bit error rate performance of private services.
[0042] In an optional embodiment, the satellite-ground fusion network communication method further includes: After receiving cellular signals through the shared frequency band, the cellular terminal decodes the cellular signals in the order of super public information, cellular public information, and cellular private information.
[0043] Here, a cellular terminal refers to a user device accessing a terrestrial cellular network, such as a smartphone, vehicle communication module, or industrial IoT terminal. In this embodiment, it specifically refers to a terrestrial user located within the satellite beam coverage area and sharing the spectrum with the satellite system. The cellular signal is a composite downlink signal received by the cellular terminal on a shared frequency band, containing three superimposed components: super-public information, broadcast by multi-beam satellites for cross-network interference coordination; cellular public information, sent by the local base station for multiple cellular users to decode together; and cellular private information, sent by the local base station and exclusive data only for that terminal. These three components completely overlap in the time and frequency domains, forming a heterogeneous non-orthogonal superimposed signal.
[0044] In practice, the cellular signals received by the cellular terminal on the shared frequency band include super-public information transmitted by the satellite, cellular public information transmitted by the ground base station, cellular private information transmitted by the ground base station, the equivalent channel gain from the satellite and base station to the terminal, and noise.
[0045] The cellular terminal first treats the cellular public information and cellular private information as interference noise and attempts to decode the super-public information. If decoding is successful, the super-public information is reconstructed and subtracted from the received cellular signal to obtain the first intermediate signal, thereby eliminating the main external interference source from the satellite system and creating a cleaner environment for subsequent cellular signal decoding. Further, the cellular terminal treats the cellular private signal as noise in the first intermediate signal and decodes the cellular public signal. If decoding is successful, the cellular public signal is reconstructed and subtracted from the first intermediate signal to obtain the second intermediate signal, at which point the signal-to-noise ratio is significantly improved. Finally, the cellular private signal is directly decoded in the second intermediate signal.
[0046] The satellite-ground integrated network communication method provided in this application converts harmful interference into an eliminable signal. Super-common information (CSI) is a structurally known and decodeable coordinated signal, not random noise, which is eliminated through serial interference cancellation, improving the signal-to-noise ratio. Furthermore, since CSI is crucial for all users, mandatory decoding of cellular CSI ensures that critical services remain available even if cellular private services fail, guaranteeing the reliability of cellular CSI services. Finally, by eliminating both CSI and cellular CSI interference sources before decoding private CSI, the throughput of private services is improved. Therefore, there is no need to reserve a protection band or reduce cellular transmission power to avoid satellite interference, allowing the satellite-ground system to operate at full capacity in the same frequency band, improving overall spectrum efficiency. Moreover, even if the base station is unaware of the satellite interference channel, the terminal can still achieve interference cancellation through blind decoding of CSI. Compared to CSI-based precoding or beam avoidance schemes, this method is less sensitive to channel estimation errors and significantly enhances system robustness in non-ideal CSI scenarios.
[0047] In an optional embodiment, the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station are determined based on the following steps: A joint optimization problem is constructed with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal. Solving the joint optimization problem yields the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0048] Here, beamforming is a technique that uses antenna arrays to spatially filter signals. By adjusting the complex weighting coefficients of each antenna element, i.e., the beamforming vector, the signal energy is concentrated towards the target user while suppressing interference to other users. Satellite beamforming is achieved by phased array antennas of multi-beam satellites to form multiple independent or partially overlapping downlink beams. Base station beamforming is achieved by large terrestrial 5G / 6G multiple-input multiple-output base stations to serve multiple users within a cell. The achievable rate is the maximum error-free transmission rate that a user can achieve under given channel conditions, interference environment, and reception strategy. The minimum achievable rate is the lowest achievable rate among all active users and serves as a core indicator for measuring system fairness.
[0049] The satellite-ground integrated network communication method provided in this application constructs a joint optimization problem with the goal of maximizing the minimum reachable rate of all satellite terminals and cellular terminals. It jointly designs the beamforming parameters of satellites and ground base stations as well as the rate allocation of various public information, realizes proactive collaborative management of cross-domain interference, and ensures the fairness of the satellite-ground integrated network.
[0050] In an optional embodiment, solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0051] Non-convex optimization problems are mathematical programming problems in which the objective function or constraints contain non-convex functions. In this application, the rate maximization problem is naturally non-convex because it contains a logarithmic function and a fractional structure of signal-to-noise ratio.
[0052] Here, auxiliary variables are introduced to simplify the original problem structure, transforming complex nonlinear terms into a more manageable form. Specific implementations may include, but are not limited to, rate-error transformation, parameterized variables in fractional programming, and matrix boosting variables in semidefinite relaxation.
[0053] The satellite-ground fusion network communication method provided in this application transforms the high-dimensional non-convex fairness beamforming problem in the satellite-ground fusion network into a series of efficiently solvable convex subproblems by introducing auxiliary variables and iterative convex approximation. This not only theoretically guarantees the convergence of the algorithm and the quality of the solution, but also achieves a unity of high fairness, low complexity, and strong robustness in engineering.
[0054] In summary, the satellite-ground integrated network communication method provided in this application effectively reduces the interference coupling between different networks by dividing the available spectrum into shared and dedicated frequency bands and performing frequency domain mapping of service data according to different information levels, thus overcoming the lack of flexibility in existing full-band superposition transmission methods. It introduces a super-common information mechanism, enabling some service information transmitted by the satellite to be jointly decoded by both satellite and ground terminals, thereby achieving early decoding and elimination of strong cross-network interference at the receiving end. This differs from existing schemes that only decode common information within the same network, significantly enhancing cross-network interference suppression capabilities. Furthermore, under imperfect channel state information conditions, a fair communication optimization framework for satellite and cellular terminals is constructed, jointly designing the beamforming parameters and various common information rates at the transmitting end. This achieves fair communication among multiple users under limited power and imperfect channel state information conditions, improving system stability and robustness.
[0055] The effectiveness of the satellite-ground fusion network communication method provided in this application will be explained below with reference to simulation experiments.
[0056] In the simulation, the satellite transmit power was set to 50W, the number of base station antennas was set to 16, the number of satellite terminals within the coverage of each satellite beam was 2, the carrier frequency was 28GHz, and the bandwidth was 500MHz. The experiments under each parameter setting are the average of 100 independent simulation results. The baseline schemes compared include: (1) Rate Split Multiple Access Method Based on Hybrid Spectrum Access and Supercommon Information (hRSMA): In a satellite-ground fusion system, hybrid spectrum access and supercommon information are combined, and rate split multiple access is used to transmit and receive information. This scheme allocates 300MHz bandwidth for the shared frequency band and 200MHz bandwidth for the satellite-dedicated bandwidth.
[0057] (2) Rate Split Multiple Access with Supercommon Information (sRSMA): In a satellite-ground fusion system, a rate split multiple access method with supercommon information is used for transmitting and receiving information. Satellites and base stations reuse the same spectrum.
[0058] (3) Rate Split Multiple Access (RSMA): In satellite-ground fusion systems, the rate split multiple access method is directly used for transmitting and receiving information. Satellites and base stations reuse the same spectrum.
[0059] (4) Spatial Division Multiple Access (SDMA): In satellite-ground fusion systems, spatial division multiple access is directly used to transmit and receive information. Satellites and base stations reuse the same spectrum.
[0060] The first experiment compared the maximum minimum fairness (MMF) rates of four schemes at different satellite altitudes. Simulations were performed on all four schemes with identical parameter configurations and zero channel error, and the MMF rates were calculated.
[0061] Figure 2 This is a comparative diagram of the maximum and minimum fairness rates provided in this application, such as... Figure 2 As shown, the performance of all schemes decreases with increasing satellite altitude. At altitudes below 10,000 km, the hRSMA scheme performs significantly better than the other schemes, indicating that the use of hybrid spectrum access improves system performance.
[0062] The second experiment compared the MMF rates of the four schemes under different base station transmit powers. Simulations were performed on all four schemes with identical parameter configurations, and the MMF rates under different channel errors were calculated.
[0063] Figure 3 This is a comparative diagram of the maximum and minimum fairness rates under different transmit powers provided in this application, as shown in the figure. Figure 3 As shown, system performance gradually improves with increasing base station transmit power, but eventually plateaus. This is because the constant satellite power limits the data rate of satellite users, ultimately restricting the overall system performance. Meanwhile, despite increased channel error, the hRSMA scheme still outperforms other schemes, and the performance difference under different channel errors is the smallest among all schemes.
[0064] The third experiment compared the MMF rates of the four schemes under different numbers of satellite beams and different numbers of cellular terminals. The four schemes were simulated under the same parameter configuration, and the MMF rates under different channel errors were calculated.
[0065] like Figure 4 and Figure 5As shown, the system performance of all four schemes declines with the increase in the number of cellular terminals or satellite beams. However, it can be seen that the increase in the number of satellite beams has a greater impact on performance degradation. This is because satellite beams cover all terminals, while base stations only cover cellular terminals. This results in cellular terminals being affected by satellite interference, while satellite terminals are not affected by base station interference. Therefore, increasing the number of satellite beams will cause interference to more terminals, thus having a more adverse impact on system performance. The hRSMA scheme, on the other hand, maintains superior system performance in this situation and exhibits a smaller performance gap for different channel errors.
[0066] In summary, this application addresses the challenges of cross-network interference, multi-user interference, and imperfect channel state information in space-ground integrated networks under spectrum sharing conditions. It proposes a rate-split multiple access (RMA) communication method based on hybrid spectrum access and super-common information. By introducing a hybrid spectrum access mechanism combining shared and dedicated frequency bands in the frequency domain, and a hierarchical rate-split structure of super-common, common, and private information at the information level, different networks and users can collaboratively suppress interference at the physical layer. Prioritizing the decoding of super-common information by all terminals enables early elimination of strong cross-network interference. Combined with the flexible interference management capabilities of RMA, stable communication performance is maintained even under imperfect channel state information. Furthermore, joint optimization of satellite and ground base station transmission parameters and rate allocation achieves fair communication between satellite and ground terminals. This application improves the spectrum utilization efficiency and system robustness of space-ground integrated networks without increasing additional spectrum resources. It is suitable for communication scenarios where multi-beam satellites and terrestrial cellular networks coexist, and has significant application value for the engineering implementation of future 6G integrated space-ground communication systems.
[0067] The satellite-ground fusion network provided in the embodiments of this application is described below. The satellite-ground fusion network described below and the satellite-ground fusion network communication method described above can be referred to in correspondence.
[0068] Figure 6 This is a schematic diagram of the structure of the satellite-ground fusion network provided in this application, as shown below. Figure 6 As shown, this space-ground integrated network may include, but is not limited to: The satellite system includes multiple multi-beam satellites. Each multi-beam satellite is used to decompose all user services into super-public information, satellite public information, and satellite private information. The super-public information is transmitted through a shared frequency band, while the satellite public information and the satellite private information are transmitted through a dedicated frequency band. The super-public information is globally shared data generated by jointly processing multicast service information carried by all beams, used to coordinate cross-network interference. The satellite public information is the common part of user information in each beam, used to coordinate multi-user interference within the satellite system. The satellite private information is the private part of user information in each beam, used to carry personalized user service data. The shared frequency band is a spectrum resource shared by the satellite system and the terrestrial cellular system, while the dedicated frequency band is a spectrum resource used independently by the satellite system. A terrestrial cellular system includes multiple terrestrial base stations, each of which is used to split local user services into cellular public information and cellular private information, and transmit the cellular public information and the cellular private information through the shared frequency band; wherein, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user.
[0069] like Figure 6 As shown, the satellite-ground converged network also includes a gateway for acquiring channel state information between the satellite and each satellite terminal, and between the ground base station and each cellular terminal, and for jointly optimizing the transmission parameters of the satellite and the ground base station based on the channel state information.
[0070] In an optional embodiment, the satellite system further includes a satellite terminal, configured to receive and decode the ultra-public information via the shared frequency band, and to receive and decode the satellite public information and the satellite private information via the dedicated frequency band in the order of satellite public information and satellite private information.
[0071] In an optional embodiment, the terrestrial cellular system further includes a cellular terminal, which is used to receive the super-public information, the cellular public information and the cellular private information through the shared frequency band, and then decode them in the order of super-public information, cellular public information and cellular private information.
[0072] In an optional embodiment, the space-to-ground fusion network further includes: A gateway is used to construct a joint optimization problem with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal; the joint optimization problem is solved to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0073] In an optional embodiment, solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
[0074] It should be noted that the satellite-ground fusion network provided in this application embodiment can execute the satellite-ground fusion network communication method described in any of the above embodiments during actual operation, which will not be elaborated in this embodiment.
[0075] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.
[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A satellite-ground integrated network communication method, characterized in that, include: Multi-beam satellites break down all user services into super-public information, satellite public information, and satellite private information. The super-public information is globally shared data generated by jointly processing multicast service information carried by all beams, used to coordinate cross-network interference. The satellite public information is the common portion of user information in each beam, used to coordinate multi-user interference within the satellite system. The satellite private information is the private portion of user information in each beam, used to carry personalized user service data. The multi-beam satellite transmits the super-public information through a shared frequency band, and transmits the satellite public information and the satellite private information through a dedicated frequency band; wherein, the shared frequency band is a spectrum resource shared by the satellite system and the ground cellular system, and the dedicated frequency band is a spectrum resource used independently by the satellite system; The terrestrial base station divides local user services into cellular public information and cellular private information; wherein, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user; The ground base station transmits the cellular public information and the cellular private information through the shared frequency band.
2. The satellite-ground integrated network communication method according to claim 1, characterized in that, The satellite-ground fusion network communication method also includes: The satellite terminal receives and decodes the super-public information via the shared frequency band. After receiving satellite signals through the dedicated frequency band, the satellite terminal decodes the satellite signals in the order of satellite public information and satellite private information.
3. The satellite-ground integrated network communication method according to claim 2, characterized in that, The satellite-ground fusion network communication method also includes: After receiving cellular signals through the shared frequency band, the cellular terminal decodes the cellular signals in the order of super public information, cellular public information, and cellular private information.
4. The satellite-ground integrated network communication method according to claim 3, characterized in that, The beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station are determined based on the following steps: A joint optimization problem is constructed with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal. Solving the joint optimization problem yields the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
5. The satellite-ground integrated network communication method according to claim 4, characterized in that, Solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
6. A space-ground integrated network, characterized in that, include: The satellite system includes multiple multi-beam satellites. Each multi-beam satellite is used to decompose all user services into super-public information, satellite public information, and satellite private information. The super-public information is transmitted through a shared frequency band, while the satellite public information and the satellite private information are transmitted through a dedicated frequency band. The super-public information is globally shared data generated by jointly processing multicast service information carried by all beams, used to coordinate cross-network interference. The satellite public information is the common part of user information in each beam, used to coordinate multi-user interference within the satellite system. The satellite private information is the private part of user information in each beam, used to carry personalized user service data. The shared frequency band is a spectrum resource shared by the satellite system and the terrestrial cellular system, while the dedicated frequency band is a spectrum resource used independently by the satellite system. A terrestrial cellular system includes multiple terrestrial base stations, each of which is used to split local user services into cellular public information and cellular private information, and transmit the cellular public information and the cellular private information through the shared frequency band; wherein, the cellular public information is data in the messages of cellular users that can be jointly decoded by some users; the cellular private information is private data exclusive to each cellular user.
7. The satellite-ground fusion network according to claim 6, characterized in that, The satellite system also includes a satellite terminal, which is used to receive and decode the super-public information through the shared frequency band, and to receive the satellite public information and the satellite private information through the dedicated frequency band, and then decode them in the order of satellite public information and satellite private information.
8. The satellite-ground fusion network according to claim 7, characterized in that, The terrestrial cellular system also includes a cellular terminal, which is used to receive the super-public information, the cellular public information and the cellular private information through the shared frequency band, and then decode them in the order of super-public information, cellular public information and cellular private information.
9. The satellite-ground fusion network according to claim 8, characterized in that, The space-ground fusion network also includes: A gateway is used to construct a joint optimization problem with the objective of maximizing the minimum reachable rate of the satellite terminal and the cellular terminal; the joint optimization problem is solved to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.
10. The space-ground fusion network according to claim 9, characterized in that, Solving the joint optimization problem to obtain the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station includes: By introducing auxiliary variables, the joint optimization problem is equivalently transformed into a non-convex optimization problem; In each iteration, the non-convex optimization problem is transformed into a series of convex optimization subproblems and solved until the auxiliary variables, the beamforming parameters of the multi-beam satellite, and the beamforming parameters of the ground base station converge, thus obtaining the beamforming parameters of the multi-beam satellite and the beamforming parameters of the ground base station.