利用巴克码窗抑制OFDM水声通信系统信道内窄带干扰性能分析

Performance Analysis of Narrow-Band Interference Suppression in Underwater Acoustic Communication Based on Barker-Code Windowed OFDM

当水声信道中存在通信带宽范围内的干扰时,会严重影响OFDM(Orthogonal Frequency Division Multiplexing)水声通信系统的误码率,针对该问题提出一种加巴克码窗的正交频分复用方法(WOFDM)并进行了理论分析。WOFDM方法通过对子载波信号在时域加载巴克码窗将信号中的窄带干扰成分近似白化,减小了由其带来的子载波频偏和相位漂移。数值仿真证明,WOFDM水声通信系统能有效地对抗由窄带干扰引起的误码,得到了和理论分析的一致的结果。

BER(Bit Error Rate) of underwater acoustics communication system based on OFDM(Orthogonal Frequency Division Multiplexing) is increased when interference within the transmission band exists.To solve this problem,a new method named WOFDM(Windowed OFDM) is proposed and analyzed in the paper.The interference could be approximately whitened after the sub-carriers be windowed by barker code in the time-domain,so the frequency shift and phase offset of the sub-carriers are decreased in the WOFDM system.Computer simulation confirms that the underwater acoustics communication based on WOFDM can effectively decrease the BER which caused by the interference,and shows the same result with theoretical analysis.