A New Narrowband Interference Mitigation Algorithm Based on Adaptive Wavelet Packet Decomposition

In order to suppress the non-stationary interference in GNSS signal, a new interference mitigation algorithm based on adaptive wavelet packet decomposition is proposed. The new algorithm combined wavelet packet decomposition (WPD) with the Convex-combined Least Mean Square (CLMS) adaptive filtering. Firstly, the energy compaction measurement (ECM) and the sub-band power ratio (SPR) are used to identify the interference sub-bands. Then the CLMS is used to process the sub-bands' wavelet packet coefficients. Finally, time domain data is obtained by the wavelet packet reconstruction. The simulation results show that the proposed method has better performance compared with fixed-step adaptive filtering algorithm under linear frequency modulation (LFM) interference.