79results about How to "Improve voice call quality" patented technology

The invention relates to a network voice device which comprises a time division multiplex bus, a plurality of digital signal processors and a plurality of subscriber line interface circuits. In the network voice device, the time division multiplex bus is divided into multiple time slots including multiple call time slots and at least one special time slot, each subscriber line interface circuit is allocated with one call time slot for call, one special digital signal processor is selected from the digital signal processors and is controlled to generate high and low interval electrical signalsto the special time slot, and the multiple subscriber line interface circuits are controlled to receive the high and low interval electrical signals from the special digital signal processor through the special time slot. The invention also provides a method for preventing the network voice device from producing noises. The network voice device and the method thereof for preventing producing the noises can effectively prevent noises generated by locking the time division multiplex bus at high level, thereby improving the network voice call quality.

The invention discloses a method and a device for conducting noise reduction on speech signals. The method comprises the steps of obtaining speech signals generated by a mobile terminal in a specified time period when the mobile terminal conducts speech communication; judging whether obtained speech signals only contain background noises or not; if obtained speech signals only contain background noises, updating a background noise library according to obtained speech signals; and if obtained speech signals do not only contain background noises, selecting background noises to be subjected to noise reduction from all background noises stored in the background noise library, and conducting noise reduction on obtained speech signals according to selected background noises. By the aid of the technical scheme, the problems that the speech communication quality of users is affected due to the fact that the good noise reduction effect can not be achieved when the mobile terminal in the prior art conducts noise reduction on speech signals according to background noises stored in advance can be solved.

The present invention provides a method for compensating lost voice service data frames, the method mainly includes: when the receiving end does not correctly receive the current voice service data frame, judging the received current voice service data frame Whether the previous voice service data frame and the next voice service data frame are active voice signals, perform corresponding operations according to the judgment result to generate voice data respectively; The voice data is synthesized to generate a compensated voice service data frame of the current voice service data frame. The invention can improve the voice call quality in the frame loss environment, and has stronger robustness to background music signals and the like.

A compensation method for frame loss after a voiced initial frame, comprising: if a first frame following a voiced initial frame is lost after the voiced initial frame is correctly received (101), choosing a fundamental tone delay inference method according to a stability condition of the voiced initial frame to infer a fundamental tone delay of the first lost frame (102); inferring an adaptive codebook gain of the first lost frame according to an adaptive codebook gain of one or more subframes received before the first lost frame, or inferring an adaptive codebook gain of the first lost frame according to an energy change of a time domain voice signal of the voiced initial frame (103); and compensating the first lost frame according to the inferred fundamental tone delay and adaptive codebook gain (104).