Research on the suppression of narrow-band interferences based on cascade open-loop IIR notch filters in satellite navigation receiver

An expression of notch bandwidth parameter α with notch bandwidth and notch depth is derived in this paper for full suppression of narrow-band interferences with certain bandwidth. Then a novel method is proposed, on the basis of cascade the open-loop IIR lattice notch filters under overall consideration of notch frequency, notch bandwidth, notch depth and real-time property. Each notch filter is responsible for full suppression of the narrow-band interference in one sub-band. Thus the single notch filter can have better notch property under the condition of enough notch depth. Analysis and results of the experiment show that the proposed method minimizes the distortion of the signal in the full suppression of narrow-band interferences.