对水声直扩通信系统的干扰效果分析

Effect analysis of underwater acoustic DSSS communication system under jamming

直接序列扩频(DSSS)技术以其良好的抗干扰性、抗衰落性在水声通信领域得到了广泛应用。因此,从通信干扰的角度来看,对直接序列扩频通信系统的干扰效果分析很有必要。首先利用Matlab对水声直接扩频通信系统进行仿真。随后用4种典型的干扰方法(宽带噪声干扰、部分频带噪声干扰、音调干扰和脉冲干扰)对此系统进行干扰。通过对4种典型干扰下系统的误比特率曲线进行对比分析。结果表明:在通信机制不明确的情况下宜使用部分频带噪声干扰;当通信机制明确时,使用音调干扰,并且证明了干扰频率的最佳位置;在一定条件下,脉冲干扰能够对直接扩频系统产生有效干扰。以上分析对特定环境下的干扰样式选取具有一定的指导意义。

Direct sequence spread spectrum（DSSS） technique is widely used in underwater acoustic communication due to its good performance on anti-interference and anti-fading. Therefore, from the point of view of communication interference, it is necessary to make an effect evaluation on DSSS communication under jamming. Firstly we simulate the underwater acoustic DSSS communication system by using matlab software. Then the system is disturbed by four typical methods（wideband noise interference, partial band noise interference, tone interference and pulse interference）. By comparing the BER curves of the system under four typical jamming, the results show that it is better to use partial band noise interference in the case of communication mechanism is not clear; when the communication mechanism is clear, we can use tone interference to interfere with the system. And the optimal frequency position of tone interference is also demonstrated; under certain conditions, pulse jamming can effectively interfere with the DSSS system. The above analysis play a guiding role for the interference pattern selection under specific circumstance.