联合小波变换与残留干扰白化的测距仪脉冲干扰抑制方法  

DME Impulse Interference Mitigation Method Based on Joint Wavelet Transform and Whitening of Residual Interference

作　　者：李冬霞[1] 高贝贝[1] 刘海涛[1] 

机构地区：[1]中国民航大学天津市智能信号与图像处理重点实验室,天津300300

出　　处：《信号处理》2015年第6期710-719,共10页Journal of Signal Processing

基　　金：国家自然科学基金(U1233117;61271404)

摘　　要：针对测距仪(DME)脉冲信号对L频段数字航空通信系统1(L-DACS1)接收机产生干扰的问题,提出一种联合小波变换与残留干扰白化的测距仪脉冲干扰抑制方法。首先通过小波变换将正交频分复用(OFDM)接收机接收的信号转换到小波域;然后利用有用信号与干扰信号小波系数的差别提取DME信号小波系数,重构DME信号,并在时域进行脉冲干扰消除;最后,接收机通过信号解交织器与逆正交变换器将残留的脉冲干扰转换为白噪声,避免了残留干扰信号造成的突发性解调错误。仿真结果显示:所提出的联合干扰抑制方法可有效消除DME信号干扰,在相同误比特率(10^(-2))条件下,本文方法较常规脉冲熄灭方法可获得5 dB以上的性能改善,提高了L-DACS1系统链路传输的可靠性。To mitigate the deleterious influence of Distance Measure Equipment （DME） impulse signal on the receiver of L-band Digital Aeronautical Communications System 1 （L-DACS1）, a new DME interference suppression method based on joint Wavelet transform and whitening of residual interference was proposed in this paper. Firstly, the received time-domain signal was transformed into wavelet-domain via wavelet transform at the Orthogonal Frequency Division Multiplexing （OFDM） receiver. Secondly, the wavelet coefficients of DME impulse signal were extracted according to their differences with those of useful OFDM signal. Then, the DME impulse interference signal was reconstructed and eliminated from the received signal in time domain. Finally, to avoid the burst errors of demodulator, the residual impulse interference was con- verted into white Ganssian noise by using the de-interleaver and inverse orthogonal transformer. Simulation results showed that the system performance can be improved over 5 dB by using the proposed method in this paper than the conventional pulse blanking method under the condition of the same bit error rate（ 10^2 ）. Therefore, the link transmission reliability of the L-DACS1 system can be improved significantly with the proposed method.

关 键 词：L波段数字航空通信系统1 正交频分复用 测距仪脉冲干扰 小波变换 

分 类 号：TN929.5[电子电信—通信与信息系统]