| 摘要 |
PURPOSE:To provide the audio compression multiplexer circuit for the communication by a radio system in which 2B+D form 4-channel data are sent through a couple of metallic wires. CONSTITUTION:A 4-channel two-way PCM/ADPCM conversion circuit 201 select optionally data from 4-channel PCM data through a transmission highway 230 based on a synchronizing signal and converts the data into ADPCM data, which are sent to a 4-channel audio multiplexer demultiplexer circuit 202, in which the 4-channel ADPCM data from the audio multiplexer demultiplexer circuit 202 are converted into PCM data, and they are sent to a reception highway 231. The 4-channel audio multiplexer demultiplexer circuit 202 multiplexes 2-channel data each from the 4-channel ADPCM data from the PCM/ADPCM conversion circuit 201 as 1 byte data into two byte data, which are sent to a DNIC 204, and demultiplexes the 2 byte data from the DNIC 204 into 4- channel ADPCM data, and they are sent to the 4-channel two-way PCM/ADPCM conversion circuit 201. |
