DSSS系統(tǒng)中自適應(yīng)時變小波包干擾抑制

提出了一種基于自適應(yīng)時變小波包變換實現(xiàn)直接序列擴頻通信系統(tǒng)時變窄帶干擾抑制的方法。該方法在自適應(yīng)時域分解的基礎(chǔ)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(jié)果表明，該方法與非時變自適應(yīng)小波包抑制技術(shù)相比較，以計算復(fù)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(guān) 鍵 詞 時域分解; 自適應(yīng)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