Modeling And Efficient Hardware Simulation Of Satellite Internet Satellite-ground Link For Satellite-borne Phased Array Antennas

With the development of modern communication technology,the theory of satellite channel modeling has been expanded from the narrow sense of satellite channel to the broad sense of satellite channel.The broad sense of satellite channel modeling refers to the channel modeling considering the influence of satellite antenna,satellite power amplifier,satellite multiplexing filter and other modules on the propagation characteristics of wireless channel.In the actual satelli.te communication scene,the satellite-borne phased array is the source of the signal,and the wireless channel is the carrier of the signal.The amplitude and phase of the space-borne phased array will affect the rank of the channel matrix and thus change the channel capacity.The polarization mode will affect the freedom of the channel,and then affect the throughput of the channel.The coupling effect will lead to power leakage between array signals and affect the signal-to-noise ratio,signal-to-dry noise ratio and channel capacity.The channel propagation characteristics of low-orbit satellite will affect the performance of satellite multi-beam jamming and link budget.Based on the above problems,a low-orbit satellite channel model integrating spaceborne phased array radiation characteristics will be established in this paper,and multi-beam interference modeling and suppression technology will be studied based on the established channel model.Finally,hardware and software joint architecture will be used to realize hardware simulation of satellite channels.The main work and innovation of this paper include:1)The coordinate transformation model between trajectory of loworbit satellite and local Cartesian coordinates is established,as well as the three-dimensional geometric model of low-orbit satellite and terminal.A three-dimensional Cartesian system model is constructed,which includes the radiation characteristics of spaceborne phased array,low orbit satellite,terminal position and beam region division,which provides a theoretical basis for subsequent channel modeling and multi-beam jamming and suppression modeling.2)This paper establishes the GBSM theoretical channel model suitable for the low-orbit satellite scene,and reconstructs it based on the radiation characteristics of spaceborne phased array through the mapping of the Angle power spectrum,analyzes the characteristics of the reconstructed channel in the time-frequency domain and Doppler domain,and simulates its space-time correlation function.The channel model is more suitable for the space-time nonstationary characteristics of low-orbit satellites and realizes the initial integration of antenna theory and wireless channel propagation theory.3)In this paper,the interference suppression technology based on Chebyshev window is studied,and the multi-beam interference model of low-orbit satellite based on reconstructed channel is constructed,and the receiving signal-to-noise ratio and multi-beam coverage of terminals at different locations are simulated.It provides theoretical basis and guidance for communication system verification and system level simulation.4)This paper establishes a low-orbit satellite multi-beam channel simulator based on hardware and software joint architecture,which improves the innovation of the channel simulator while preserving the realtime performance of the channel simulator,optimizes the resource occupation of the channel simulator and reduces the difficulty of implementation.Compared with the existing simulators,the influence of spaceborne phased array multibeam on the channel is considered.