摘要
当深空通信路径距太阳较近时,受太阳闪烁等电磁活动的影响,无线电波会受到严重干扰,导致传输误码率增高甚至通信中断.为了保持飞行器与地面或飞行器之间的正常通信,对深空信道传输特性进行研究.包括信号的幅度统计特性、信道的相干时间和相干带宽、太阳闪烁相对于地面多径及电离层闪烁的主要区别等,并建立了太阳闪烁下的深空信道模型,提出了一种选择进入非频率选择性慢衰落信道时间最久的信号带宽选择方法.仿真结果表明:在不同日张角特别是较小日张角下,使用该方法选出的信号带宽比使用其他信号带宽拥有更低的误码率.
Abstract For deep space communication paths close to the sun causing solar scintillation of radio waves and increasing bit error rate(BER),the approach of choosing the signal bandwidth in the non-frequency selective and slow fading channel with maximum time was proposed.The deep space communication channel model was built based on Rician fading channel model.The statistical characteristics of the amplitude,the coherence time and the coherence bandwidth of the channel were used.The difference among solar scintillation,mobile multipath and ionosphere scintillation was compared.Based on the change of the coherence time and coherence bandwidth with solar elongation angle,the time-selective and frequency-selective characters were determined.Simulation results show that at different little solar elongation angle,especially the small one,the BER of the signal bandwidth chosen by the proposed approach is better than the BER of other signal bandwidth.
出处
《电波科学学报》
EI
CSCD
北大核心
2015年第3期417-422,共6页
Chinese Journal of Radio Science
基金
CEMEE国家实验室开放课题基金项目(CEMEE2014K0105B)
关键词
相干带宽
相干时间
衰落信道
信号带宽
太阳闪烁
coherence bandwidth
coherence time
fading channel
signal bandwidth
solar scintillation
