单音及部分频带干扰下DSSS系统性能分析

Performance analysis of DSSS system under Mono and partial band interference

直接序列扩频技术(DSSS)是将原本信号的带宽扩展到一个更宽的频带范围内。但是卫星的带宽是非常宝贵的资源,在使用卫星通信时一般来说只能分配到1~2 MHz的带宽,因此,对于某些突发干扰环境导致通信中断的情况,可以采用降低传输速率的方法,以实现在分配带宽内的扩频。不同干扰样式对于DSSS系统来说干扰效果是不一样的,因此,主要分析降低通信速率到2.4 kHz情况下单音和部分频带干扰样式对DS-QPSK系统的干扰效果。实验结果表明,在保留使用2 MHz带宽的前提下,降低通信速率可以有效地实现最低限度通信,同时系统的抗干扰效果与干扰信号的相位和频差都具有一定的关系。

Direct sequence spread spectrum technology extends the bandwidth of the original signal to a wider frequency range. Satellite bandwidth is a valuable resource and can usually be allocated to 1~2 MHz of bandwidth in satellite communications. Therefore, for some interference environments, it is necessary to reduce the transmission rate to achieve spread spectrum within the allocated bandwidth. However, different interference patterns are not the same for DSSS systems. Therefore, to understand the anti-interference performance of DS spread spectrum systems, it is necessary to analyze the impact of different interference patterns on the system. The influence of monophonic and partial band interference patterns on the DS system is analyzed mainly. The experimental results show that under the premise of retaining the 2 MHz bandwidth, the minimum communication can be realized effectively by reducing the communication rate. At the same time, the anti-interference effect of the system has a certain relationship with the phase and frequency difference of the interference signal.