| 摘要 |
In a mobile telephone set, a speech coder is provided for converting an analog speech signal to a digital speech signal. A voice activity sensor determining whether the analog speech signal is present or not. A storage level detector determines the amount of a data signal waiting for transmission from a non-telephonic communications apparatus. A switching control logic determines the rate for the speech coder according to the outputs of the voice activity sensor and the storage level detector. When the analog speech signal is present and the amount of the waiting data signal is zero, the data rate is set at a high rate and a digital speech signal from the speech coder is transmitted along with an indication of the high data rate. When the analog speech signal is present and the amount of the waiting data signal is non-zero, the data rate of the speech coder is set at a rate which is lower than the high data rate and is variable in accordance with the amount of the waiting data signal and the digital speech signal from the speech coder and the data signal from the non-telephonic communications apparatus are transmitted along with an indication of the variable data rate. When the analog speech signal is absent and the amount of the waiting data signal is non-zero, the data signal from the apparatus is exclusively transmitted.
|
