Research on denoising methods of linear CCD spectrum data using combined filter based on wavelet threshold

Due to the influence of various factors, such as the test environment, the instrument itself and the target's spectrum characteristics, the measured linear CCD spectrum data contains noise. If the noise can not be removed effectively, the results of spectrum detection will be affected. Since the noise contained in the linear CCD spectrum data is mainly Gauss white noise and impulsive noise, a combined filter method based on wavelet threshold and median filter is proposed to denoise the linear CCD spectrum data in this paper. The simulation spectrum data and the measured spectrum data captured by spectrum instrument are used to check the validity of this method. The simulation results show that using the combined filter method, the noise of the spectrum data can be effectively reduced, and the signal-to-noise ratio of the spectrum signal is improved.