| 摘要 |
PURPOSE: A call quality improving apparatus of a variable transmission voice codec which applies a hysteresis timer for improving call quality is provided to prevent the change of variable voice codec transmission rate by varying the transmission rate. CONSTITUTION: In case a transmission rate is allocated, an SNR(Signal to Noise Raito) change sensing unit(110) senses the change of the signal-to-interference ratio. The signal-to-interference ratio change sensing unit compares the threshold and the change of the sensed SNR. If the threshold is greater than the change of the signal-to-interference ratio, a timer driving unit(120) drives a hysteresis timer. A transmission rate sustaining unit(130) maintains the transmission rate of the variable transmission voice codec until the hysteresis timer is terminated. |
