Broadband excitation signal synthesis method based on segmented expansion

Abstract

The invention provides a broadband excitation signal synthesis method based on segmented expansion. According to the method, two methods of narrow-band excitation spectrum translation and white noise excitation are combined, narrow-band excitation signals pass through a low-pass filter, first frequency-band excitation signals are outputted, after the translation of the first frequency-band excitation signal spectrum and high-pass filtering of the first frequency-band excitation signals are performed, second frequency-band excitation signals are obtained, white noise via energy adjustment is multiplexed by gain factors to obtain third frequency-band excitation signals, and finally, the first frequency-band excitation signals, the second frequency-band excitation signals, and the third frequency-band excitation signals are synthesized to form complete broadband excitation signals. According to the method, the harmonic structure of the excitation signals can be well reserved, too many artificial harmonic waves are not introduced, the operation complexity of the algorism is not high, the realization is easy, the performance of the conventional bandwidth expansion technology is improved, and the communication quality of narrow-band voice is improved.

Description

technical field [0001] The present invention relates to the technical field of speech signal processing, and more specifically, to a method for synthesizing broadband excitation signals based on segment expansion. Background technique [0002] Due to the limitation of its transmission bandwidth, the traditional telephone network can only communicate with narrowband voice. Although the narrowband voice can meet the basic communication requirements, the communication quality is greatly reduced. Due to economic reasons, it is impossible to realize real broadband transmission in a short period of time on the old telephone network. The emergence of artificial voice bandwidth expansion technology solves this problem. This technology does some processing at the receiving end of the telephone network, and artificially adds some missing frequency band components to the received narrowband voice signal, so that the receiving end outputs broadband with higher auditory quality. Speech ...

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Problems solved by technology

Although these three methods are relatively mature at present, their disadvantages lie in that the appropriate harmonic structure must be preserved in the synthesized excitation signal, and too many artificial harmonics must not be introduced, because too many artificial harmonics will affect the The original harmonic structure will cause damage; the computational complexity of the algorithm should not be too high, otherwise the algorithm will be difficult to implement

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