Low SNR (signal to noise ratio) speech noise reduction method

Abstract

The invention discloses a low SNR (signal to noise ratio) speech noise reduction method. The method comprises the following steps of: framing an input voice signal, multiplying each frame of the input voice signal into a Hamming window, carrying out time-frequency transformation and calculating spectral power distribution of the signal; according to a state of the received signal, judging to carry out gain oscillation detection on the received signal and updating bottom noise spectral power distribution; after calculating spectral distribution, inspecting an SNR and carrying out MMSE (Minimum Mean Square Error) noise suppression; calculating a frame SNR and storing and updating the frame SNR in a certain recent time; carrying out spectrum enveloped multistate transfer, and according to a state output of the state transfer, judging whether the input signal is speech or noise; carrying out frequency-time transformation and window overlapping on the signal subjected to noise reduction, carrying out speech head protection on the output signal, and according to a silence detection result, outputting the speech or silenced voice subjected to noise reduction. According to the invention, the short-wave communication noise can be effectively inhibited, quality of communication voice is improved, and effectiveness of speech noise reduction is technically ensured.

Description

technical field [0001] The invention relates to the field of speech signal processing of radio communication, in particular to a speech noise reduction method with low signal-to-noise ratio. Background technique [0002] Voice communication is the most basic service in wireless communication. At present, analog voice is still the mainstay in many fields, such as aircraft and ground communication, remote command communication, radio broadcasting and so on. In these applications, affected by various factors such as multipath, fading, and reflection of the wireless channel, the voice signal will be distorted and fading during transmission, and at the same time, the antenna will receive various noise signals on the wireless channel, resulting in the received Voice has a large noise interference. Especially when there is no voice signal transmission, the receiving device will play out various received wireless channel noise signals as voice signals, causing the communicator to s...

AI Technical Summary

Problems solved by technology

However, when the signal-to-noise ratio is low and the energy of the noise signal is greater than or much greater than the voice signal, the traditional method often cannot effectively detect the voice signal and reduce the noise, resulting in the loss of words and sentences in the voice communication, and the voice distortion output by the noise reduction is relatively large.

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