基于FFT和FRFT的非平稳干扰估计和抑制  

Estimation and Suppression of Broadband Non-stationary Interference Based on FFT and FRFT

作　　者：邵高平[1,2] 安建平[1] 

机构地区：[1]北京理工大学信息与电子学院,北京100081 [2]解放军信息工程大学信息工程学院,郑州450002

出　　处：《数据采集与处理》2010年第2期160-164,共5页Journal of Data Acquisition and Processing

摘　　要：提出了一个基于快速傅里叶变换(FFT)和分数阶傅里叶变换(FRFT)的线性频率调制(LFM)干扰参数的估计和抑制方法。通过FFT粗略估计和FRFT精确估计,确定LFM干扰在分数阶傅里叶域所处的旋转角度,估计出LFM的相关参数,利用最小二乘法综合出LFM干扰信号;然后从接收的信号中减去,有效地抑制LFM干扰。性能仿真分析表明,该方法较好地改善了误码率性能,降低了计算的复杂度,提高了系统处理的实时性。A fast Fourier transform（FFT） and fractional Fourier transform（FRFT）-based interference suppression scheme for wideband nonstationary interference is proposed in direct sequence spread spectrum communication. The interference parameters are coarsely estimated by FFT and are accurately estimated by FRFT. The nonstationary interference can be synthesized from received signals by least-squares methods. The synthesized interference is subtracted from the received signals in the time domain and the signal-to-interference ratio is increased on the input of the correlator. Compared with the masking interference excision method, the scheme is more stable on bit error rate （BER） performance and simple on the computational complexity.

关 键 词：直接序列扩频 干扰抑制 线性频率调制 傅里叶变换 分数阶傅里叶变换 

分 类 号：TN911.7[电子电信—通信与信息系统]