Signal Bandwidth Estimation Based on the Wavelet Reconstruction

Abstract

At low SNRs, the analog signal will be swamped by noise. Aiming at the low estimation accuracy of the traditional signal bandwidth estimation algorithms, a signal bandwidth estimation method based on the Wavelet reconstruction is proposed in this paper. Firstly, the influence of noise is reduced by means of data segmentation cross-correlation. Secondly, the envelope of signal amplitude spectrum is extracted by the wavelet low-frequency reconstruction. Finally, according to its envelope, the boundary can be found of signal amplitude spectrum by the difference operation. The estimation is completed of the signal zero-crossing bandwidth. In this method, the wavelet reconstruction is applied to signal bandwidth estimation for the first time, which can reduce the negative impact of signal randomness on the spectrum envelop. In addition, the extreme point searching algorithm is designed to confirm the upper and lower frequency bands of the reconstructed spectrum envelope, which is easy to implement and can be directly applied in the engineering field. The experimental results show that the proposed method is robust and can achieve good results at low SNRs.