应用于中继卫星通信系统的16QAM-TCM技术研究  

16QAM-TCM Technology Research Applied in Relay Satellite Communication System

作　　者：张秀宁 李正岱 张旭 ZHANG Xiuning;LI Zhengdai;ZHANG Xu(Beijing Research Institute of Telemetry,Beijing 100076,China)

机构地区：[1]北京遥测技术研究所,北京100076

出　　处：《遥测遥控》2024年第2期42-49,共8页Journal of Telemetry,Tracking and Command

基　　金：中国航天科技集团自主研发项目“卫星中继用户终端子系统”。

摘　　要：网格编码调制技术可以在不改变信息传输频谱带宽的条件下,改善信噪比,减少发射功率,降低误码率,其实现的方法是分割星座图形成子集,逐步增大星座图中信号点之间的最小欧氏距离。本论文在项目组自研的中继卫星通信系统仿真平台上,仿真了8PSK与16QAM-TCM两种调制技术的解调性能,仿真曲线反映了误比特率需求与所需信噪比之间的关系。仿真结果表明:(1)在理想信道条件、I/Q(Inphase/Quadrature,同相/正交)幅相不平衡、幅频特性、群时延、相位噪声、功率放大器饱和点条件下,假设误比特率需求为1E-7,16QAM-TCM技术的信噪比需求与8PSK调制技术的信噪比需求相比,分别可节省8.85 dB、9.04 dB、8.45 dB、10.2 dB、8.5 dB、14.6 dB的信噪比;(2)在非线性信道条件下,当信噪比增大时,8PSK调制技术的误比特率在1E-3数量级附近波动,不再变化;(3)假设需求的误比特率为1E-7,16QAMTCM调制技术非线性信道信噪比仿真值与理想信道信噪比仿真值相比,损失了4.8 dB。Trellis coding modulation technology can improve the signal-to-noise ratio,reduce the transmission power,and lower the bit error rate without changing the bandwidth of the information transmission spectrum.The realization method is to divide the constellation map to form a subset and gradually increase the minimum Euclidean distance between the signal points in the constellation map.In this paper,the demodulation performance of 8PSK and 16QAM-TCM modulation techniques is simulated on the simulation platform of a relay satellite communication system developed by the project team.The simulation curve shows the relationship between the required bit error rate and signal-to-noise ratio.The simulation results demonstrate:①under the channel conditions of an ideal channel,I/Q amplitude and phase imbalance,amplitude and frequency characteristics,group delay,phase noise,power amplifier saturation,if the required BER is 1E-7,compared to 8PSK modulation technology,the signal-to-noise ratio of 16QAM-TCM technology saves 8.85 dB,9.04 dB,8.45 dB,10.2 dB,8.5 dB,and 14.6 dB,respectively;②under the channel conditions of nonlinear,correspondingly along with increasing of the signal-to-noise ratio,the BER of 8PSK modulation technology fluctuates around the order of 1E-3;③if the required BER is 1E-7,compared with the ideal channel SNR simulation result,the non-linear channel SNR simulation result of 16QAM-TCM technology loses 4.8 dB.

关 键 词：网格编码调制 中继卫星通信系统仿真 16QAM-TCM 8PSK 非线性信道 

分 类 号：TN927.3[电子电信—通信与信息系统] V474.21[电子电信—信息与通信工程]