面向多类用户的卫星前向链路复合波形设计

User-oriented Composite Waveform Design for Satellite Forward Link

针对卫星前向链路用户需求种类多样的情况,提出了一种复合波形的设计方法;将接收端为特殊类型用户的小功率信号进行一次扩频的基础上,采用二次扩频的方式使小功率信号与常规的大功率信号复合;尽可能减小波形复合对各信号传输性能的影响,并且保证复合波形中信号的兼容性;进行了复合波形生成与接收方法的设计,并通过建立仿真系统分析了复合波形的传输性能;在复合波形的功率分配比为6dB以上时,对大功率信号带来的性能损失在2dB以内,且复合波形中各信号传输性能在可接受范围内。

In view of the diversity of satellite forward link users’ needs,a design method of composite waveform is proposed.On the basis of the first spread spectrum of the low power signal for special type of users at the receiving end,the second spread spectrum method is adopted to make the low power signal compounded with the conventional high power signal.The effect of waveform recombination on the transmission performance of each signal is minimized,and the compatibility of signals in the composite waveform is ensured.The method of generating and receiving composite waveform is designed,and the transmission performance of composite waveform is analyzed by establishing simulation system.When the power distribution ratio of the composite waveform is more than 6 dB,the performance loss of the high-power signal is less than 2 dB,and the transmission performance of each signal in the composite waveform is acceptable.