太阳闪烁影响下的星际通信链路参数设计

Interplanetary Communication Parameters Design under Influence of Solar Scintillation

针对太阳闪烁作用于星际通信链路而产生的幅度闪烁、频谱扩展、相位闪烁、时延扩展问题,提出一种适用于星际通信链路的参数设计方法。该方法根据通信链路与太阳的几何关系,计算太阳风中等离子体作用于无线电波的幅度统计特性、时间谱特性,将计算结果作为通信链路的频率选择、传输信号带宽设计、调制方式选择、锁相环路带宽设计的约束条件,并以某空间探测任务为例进行了S、X、Ka三种频段下的信号传输性能仿真分析,结果表明,在太阳闪烁指数m <0. 3的情况下,采用Ka频段+8PSK调制相结合的方式,对于太阳闪烁的抵抗能力最强。该方法设计的参数能够降低太阳闪烁对通信链路的影响,可作为工程实际系统设计的参照。

In order to resist the solar scintillation influence of its magnitude blink,spectrum spread,phase blink,and delay time extension,a method of parameters design suitable for the interplanetary communication link is proposed.According to the geometrical relationship between the communication link and the sun,this method calculates the amplitude statistical properties and time spectrum characteristics when the solar scintillation acting on the radio waves. The calculated results are used as the constraints for the frequency of the communication link,the bandwidth design of the transmit signal,the selection of the modulation mode,and the design of phase-locked loop bandwidth. Take a space exploration mission as an example,the signal transmission performance at the three frequency bands of S,X and Ka are simulated. The results shows that when the scintillation index m 0. 3,the Ka-band frequency and 8 PSK modulation are the best selections to resist the solar scintillation in the designed communication parameters. This method can be used as a reference for actual engineering system design,to reduce the influence of the solar scintillation.