大规模卫星星座组网的码分多址干扰分析  

Analysis of CDMA interference in large-scale satellite constellation

作　　者：徐可笛 徐兆斌[1,2] 郭晓旭 杨嘉 成恒飞 金仲和[1,2] XU Kedi;XU Zhaobin;GUO Xiaoxu;YANG Jia;CHENG Hengfei;JIN Zhonghe(Micro-Satellite Research Center,Zhejiang University,Hangzhou 310027,China;Key Laboratory of Micro-Nano Satellite Research,Zhejiang Province,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学微小卫星研究中心,杭州310027 [2]浙江大学浙江省微纳卫星研究重点实验室,杭州310027

出　　处：《北京航空航天大学学报》2024年第9期2885-2892,共8页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金面上项目(62073289);国家自然科学基金(U21A20443)。

摘　　要：码分多址(CDMA)的通信体制是大规模卫星星座组网的主要部分,针对星间多通道通信存在多址干扰的情况,对其接收链路建立模型,描述灵敏度与比特能量噪声密度比(BENR)、设备采样信噪比(SNR)的关系,并分析多址干扰和加性白噪声对SNR的影响。在MATLAB仿真不同接收、干扰功率时的BENR与灵敏度,仿真结果表明,信干比(SIR)大于0 dB时,干扰信号对灵敏度影响较小,而维持高灵敏度时可抵抗−6 dB干扰。建立3个发射器和1个接收器的实验平台,由Chipscope、MATLAB软件处理数据,得到符合实际应用需求的接收灵敏度,实验结果表明,SIR大于0 dB时,接收灵敏度可达−107 dBm,高灵敏度下可抵抗−9 dB干扰,误差影响因素为电路噪声。理论分析与实测相符,为实际低轨卫星星座组网的设计奠定了基础。Code division multiple access(CDMA)communication system is the main part of large-scale satellite constellation network.In the case of multiple access interference in multi-channel communication between satellites,the receiving link is modeled.This study elucidates the correlation between bit energy to noise density ratio(BENR)and device received signal-to-noise ratio(SNR),while also investigating the impacts of additive white noise and multiple access interference on SNR.The BENR and sensitivity are simulated in MATLAB with different receiving and interference power.The simulation demonstrates that the interference signal exerts a diminished impact on the sensitivity when the signal-to-interference ratio(SIR)exceeds 0 dB.The receiver can withstand−6 dB interference while maintaining high sensitivity.An experimental platform for three transmitters and one receiver is established.Data is processed by Chipscope and MATLAB software to obtain the received sensitivity that meets the actual application requirements.Experiments show that when SIR is greater than 0 dB,the received sensitivity can reach−107 dBm.The receiver can resist−9 dB interference at high sensitivity.Error is affected by circuit noise.The congruence between the measured data and the theoretical analysis provides a fundamental basis for the development of the real low-orbit satellite constellation network.

关 键 词：星座 卫星通信 码分多址 多址干扰 灵敏度 

分 类 号：V11[航空宇航科学与技术—人机与环境工程]