| 摘要 |
PURPOSE: A method for detecting a DTMF(Dual Tone Multi Frequency) signal in a mobile communication system is provided to solve a delay problem due to a DTMF detection algorithm in case that a detection function is implemented in the vocoder of a base station controller. CONSTITUTION: A vocoder in a base station controller executes a DTMF detection algorithm for the first frame, 160 samples, once and stores non-processed 64 samples in a buffer(S101,S102). The vocoder adds the non-processed 64 samples to the second frame and executes the DTMF detection algorithm twice consecutively(S103,S104). Then the vocoder stores non-processed 32 samples in the buffer(S105). The vocoder adds the non-processed 32 samples to the third frame and executes the DTMF detection algorithm twice consecutively(S106,S107). Then the vocoder checks whether the fourth frame is inputted(S108). In case that the fourth frame is not inputted, the vocoder finalizes the DTMF detection procedure. If the fourth frame is inputted, the vocoder returns to the first step(S109). |
