Noise decrease and the comfort noise gain control which use with the barque zone waina filter and linear attenuation

摘要

It improves the removal of the noise in the telephone the barque zone correction waina filter (121) noise control and the linear noise decrease which are used (122) with combination. The detector which detects long silent section is connected by the output of the noise restrictive measure, controls noise control or the selection of noise decrease. The gain smoothing filter, when noise decrease is used, has big time constant, offers the progressive change to another level from a certain level. Comfort noise is inserted, it was detected just between the long silent sections where generates comfort noise renewing the data which by smoothly.