Noise Reduction by Noise-Adaptive Spectral Magnitude Expansion

Noise-adaptive spectra magnitude expansion bridges the gap between compandors used to overcome the limited dynamic range of a transmission channel and noise suppression techniques such as spectral subtraction or spectral short-time wiener filtering. The underlying idea of noise-adaptive spectral magnitude expansion is to adapt the crossover point of the spectral magnitude expansion in e;ach frequency channel based on the noise level. When no restrictions are imposed or the expansion characteristic, many types of spectral short-time filtering, such as spectral subtraction and spectral short-time Wiener filtering, can be considered as special cases of noise-adaptive spectral magnitude expansion.