Special Issue: 6G-Oriented Space-Integrated-Ground Information Network

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For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Space-Integrated-Ground Information Networks    2021, 2 (4): 1-1.   DOI: 10.11959/j.issn.2096-8930.2021037-1 Abstract （159）   HTML （35）    PDF（pc） （509KB）（247）       Knowledge map    Save Reference | Related Articles | Metrics Select Research on Network Architecture for the Space-Integrated-Ground Information Network in 6G Hui XU, Shaohui SUN Space-Integrated-Ground Information Networks    2021, 2 (4): 2-9.   DOI: 10.11959/j.issn.2096-8930.2021037 Abstract （665）   HTML （184）    PDF（pc） （1097KB）（682）       Knowledge map    Save The requirements and the fl exible and reconfi gurable network architecture for the space-integrated-ground information network was proposed based on analyzed the 6G network vision and challenges faced by the space-integrated-ground information network.Based on the proposed network architecture, the intelligent network management and control architecture and the virtualization technology of the space-integrated-ground information network were proposed to realized the dynamic confi gurability of the network. Table and Figures | Reference | Related Articles | Metrics Select Research on Architecture of LEO Satellite Internet of Things and Key Technologies Xiaojin DING, Tao HONG, Rui LIU, Wentao PENG, Gengxin ZHANG Space-Integrated-Ground Information Networks    2021, 2 (4): 10-18.   DOI: 10.11959/j.issn.2096-8930.2021038 Abstract （488）   HTML （92）    PDF（pc） （2290KB）（640）       Knowledge map    Save First, we analyzed the composition and demand characteristics of LEO satellite IoTs, and designed an architecture of LEO satellite IoTs.Second, to extracted characteristics of electromagnetic environment and channel, we studied electromagnetic environment and channel sensing methods through constructing neural network model.Then, we investigated an active terminal-identifi cation method for detecting active terminals.Finally, considered multiple-input multiple-output as the main approach to improved the capacity of terrestrial mobile communication systems, we explored a pair of algorithms of mining satellite spatial resources for realizing the collision mitigation and capacity improvement of LEO IoT terminals.Simulation results showed that the designed method sofmining spatial-domain resources could mitigated eff ectively signal collisions among IoT terminals, and improved signifi cantly the concurrent accessing number of LEO satellite IoT terminals. Table and Figures | Reference | Related Articles | Metrics Select Research Status of Space-air-ground Integrated Network and Application Prospects of New Technologies Xiaokai ZHANG, Daoxing GUO, Bangning ZHANG Space-Integrated-Ground Information Networks    2021, 2 (4): 19-26.   DOI: 10.11959/j.issn.2096-8930.2021039 Abstract （1222）   HTML （214）    PDF（pc） （963KB）（1217）       Knowledge map    Save To achieve the demand of all-time all-area coverage of wireless communications, space-air-ground integrated network (SAGIN) is important systematic development direction with global coverage, optional reception, and proportional demand service, which deeply integrate the satellite-based network, aerial-based network, and terrestrial-based network to break down the systematic barriers of each network and give full play to the functions of diff erent network dimensions.The development process of the SAGIN from the aspects of policy orientation, academic innovation, standards and norms were discussed.At the same time, the applications of the new emerged technology in the SAGIN were prospected, and the possible development direction of the SAGIN in the future was discussed. Table and Figures | Reference | Related Articles | Metrics Select Research on Random Access Technology of Inter-Frame Interference Cancellation for 6G Satellite Internet of Things Yu XU, Qing GUO Space-Integrated-Ground Information Networks    2021, 2 (4): 27-33.   DOI: 10.11959/j.issn.2096-8930.2021040 Abstract （184）   HTML （25）    PDF（pc） （1952KB）（350）       Knowledge map    Save In 6G, one of the important application scenarios is ultra-massive machinetype communications, which is mainly oriented to the application scenarios of concurrent access of massive terminals such as the satellite Internet of Things.How to design an access mechanism that can meet the concurrent access service requirements of large-scale users in machine communication scenarios for the future 6G satellite communication network is an important problem to be solved.A random access protocol based on intra-frame interference cancellation was proposed.In this protocol, each access user who needs to transmit data sends multiple packet copies in one frame, and the receiver can successfully receive packets from multiple users in confl icting time slots by using interference cancellation algorithms in the frame.Compared with the traditional random access mechanism, this mechanism can greatly improve the throughput performance in the scenario of multi-user concurrent access. Table and Figures | Reference | Related Articles | Metrics Select Research on the NB-IoT Random Access in LEO Satellite IoT Haodong LIU, Zhong ZHENG, Wenjin WANG, Li YOU, Xiqi GAO Space-Integrated-Ground Information Networks    2021, 2 (4): 34-42.   DOI: 10.11959/j.issn.2096-8930.2021041 Abstract （441）   HTML （57）    PDF（pc） （1230KB）（560）       Knowledge map    Save Narrowband internet of things (NB-IoT) technology is widely used in data communications for a large number of low-speed and low-power devices, but it is diff cult to provide services for remote areas that cannot be covered by terrestrial networks.With its global coverage and low cost, the LEO satellite constellation can supplement and expand the terrestrial NB-IoT infrastructure, providing an eff ective solution for the space-based internet of things.Facing the application requirements of space-based internet of things, on the basis of reviewing the NB-IoT system architecture, the challenges of channel environment high dynamic delay and frequency off set faced by the application of NB-IoT technology in the LEO satellite constellation scenario were analyzed.For the uplink random access process, an eff ective user detection and timing synchronization method was designed, which had the advantages of high performance and low complexity, and provided an eff cient receiving method for the LEO satellite NB-IoT uplink random access synchronization. Table and Figures | Reference | Related Articles | Metrics Select Sensing-Based Spectrum Sharing Method in Satellite-Terrestrial Network Jing HU, Dongming BIAN, Xiang TIAN, Yinxia ZHU, Jian ZHANG Space-Integrated-Ground Information Networks    2021, 2 (4): 43-52.   DOI: 10.11959/j.issn.2096-8930.2021042 Abstract （189）   HTML （23）    PDF（pc） （2348KB）（406）       Knowledge map    Save Considering the spatial possibility of opportunistic spectrum sharing, sensing-based spectrum sharing method ws applied in the satellite-terrestrial network.The sensing-throughput tradeoff problem was studied, and the throughput is a concave function of the sensing duration was proved.In order to further improved the satellite uplink throughput, the multi-slots sensing method and the cooperative sensing method were proposed.Computer simulations showed that the optimal sensing duration could maximized the uplink throughput, and the multi-slot sensing method or the cooperative sensing method could further improved the throughput of satellite network. Table and Figures | Reference | Related Articles | Metrics Select Robust Beamforming Algorithm for Multibeam Satellite Communication Based on Downlink NOMA Pengcheng KAN, Zining WANG, Huaicong KONG, Jian OUYANG, Min LIN Space-Integrated-Ground Information Networks    2021, 2 (4): 53-59.   DOI: 10.11959/j.issn.2096-8930.2021043 Abstract （209）   HTML （17）    PDF（pc） （1670KB）（247）       Knowledge map    Save To improved the spectrum efficiency of multibeam satellite system and meet the requirement of multi-access, a robust beamforming and power allocation scheme based on non-orthogonal multiple access (NOMA) was proposed.Under the condition that the imperfect channel state information was known, fi rstly, a power minimization problem subject to probability constraints of users’ quality of service requirement and earth stations’ interference-to-noise ratio was formulated.In order to address the non-convex problem, we then adopted Bernstein inequality to converted the probability constraints into deterministic forms and decomposed the original problem into beamforming sub-problem and power allocation sub-problem, and the robust design was conducted by alternating optimization.Simulation results showed that the proposed scheme has better robustness and eff ectiveness compared with other existing schemes. Table and Figures | Reference | Related Articles | Metrics Select On-board Multi-User Detection Algorithm Based on Conditional Neural Process Yilun LIU, Liang JIN, Jiali LI, Lidong ZHU Space-Integrated-Ground Information Networks    2021, 2 (4): 60-65.   DOI: 10.11959/j.issn.2096-8930.2021044 Abstract （121）   HTML （14）    PDF（pc） （1452KB）（125）       Knowledge map    Save With the characteristics of all-terrain, all-weather and seamless coverage, satellite communications have become a potentially important part of 6G.An important prerequisite for achieving satellite intelligence is that the satellite have on-board processing capabilities.Multi-user detection (MUD) is a classic method of suppressing multiple access interference (MAI) in wireless communication, such as MMSE, Gaussian processregression (GPR) and other algorithms.Due to the inverse matrix required in the detection process, the algorithm complexity is usually cubic, and it is diff cult to directly apply to satellite platforms because of its limited processing capabilities.The conditional neural process combined the characteristics of the low complexity of the neural network and the data-eff cient of the Gaussian process.The neural network was used to parameterized the Gaussian process to avoided the inversion of the matrix, thereby reduced the computational complexity.The application of conditional neural process in MUD was studied.The simulation results showed that, while reduced complexity, conditional neural process also greatly improved the performance of bit error rate (BER). 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