一种中频抗窄带干扰自适应滤波方法

An Adaptive Filtering Algorithm for Narrowband Interference Suppression at Intermediate Frequency

根据实际的技术需求,针对信号传输带内可能存在领近频率的干扰,采用自适应滤波技术,抑制带内的窄带干扰。该方法是一种数字滤波方法,对中频时域信号进行A/D采样,通过FFT(快速傅里叶变换),变换为相应的离散频域信号,应用抗窄带干扰的自适应滤波算法,消除其频带内的窄带干扰,而同时基本保留有效信号,通过IFFT(反变换)将滤波后的频域信号转换为时域信号,并D/A输出。

According to practical technical requirements, aiming at possibly existing nearby - frequency interference from nearby satellites in signal transmission, the paper provides a method of adaptive filtering to minimize the narrowband interference. The method is a digital filtering algorithm, first it uses the A/D to sample the incoming intermediate frequency continuous signal in time domain, then uses FFT （Fast Fourier Transform） to transform the signal to the corresponding discrete signal in frequency domain, then applies the adaptive filtering algorithm to eliminate the unwanted narrowband interference within the band, while keeping the wanted signal almost untouched. And finally, through IFFT, transforms the processed signal back to the time- domain signal for D/A output.