提出了一種基于自適應時變小波包變換實現直接序列擴頻通信系統時變窄帶干擾抑制的方法。該方法在自適應時域分解的基礎上，利用小波包變換多分辨分析能力和良好的時頻特性進行頻率分解，將有用信號和干擾分離，然后將受擾頻帶置零后進行小波包合成，達到濾除時變窄帶干擾的目的。計算機仿真結果表明，該方法與非時變自適應小波包抑制技術相比較，以計算復雜度為代價，能更靈活有效地跟蹤和定位時變干擾，提供較好的誤碼率性能。
關 鍵 詞 時域分解; 自適應小波包變換; 時變干擾; 擴頻通信

Abstract In this paper, an adaptive time-varying wavelet packet transform (WPT) excision algorithm is proposed for time-varying narrowband interference (TVNBI) in DSSS communication. Based on time decomposition, this method takes advantage of multi-resolution capability and favorable time-frequency character of WPT to perform frequency decomposition, separate desirable signal from jamming signal, the DS signal is recovered by wavelet reconstruction after setting zeros to polluted frequency sub-band. Computer simulation results show that compared with the non-time-varying WPT technique, this method could efficiently search and locate the TVNBI, provide satisfied bit error rate (BER) performance at the cost of increasing computation.
Key words time decomposition; adaptive wavelet packet transform; time-varying interference; spread spectrum