| 摘要 |
Apparatus for compressing a voice message prior to radio transmission includes a speech recogniser 3 and a comparator 6 for identifying those words which are redundant to the meaning of the message and eliminating them from the transmitted signal. Alternatively longer words may be replaced with shorter synonyms. A syntax extractor 4, produces an error check signal which is received at the receiver to verify the accuracy of the received message and for relaying this back to the transmitter. The speech recogniser 3 compares each word of a digital bit stream from encoder 1 with stored templates and recognised words are compared at 6 with templates of redundant words stored at 7. The compressed word chain from comparator 6 along with the output of syntax extractor 4 are modulated at 8 and transmitted. In the receiver (fig.2 not shown), the received signal is demodulated and decoded for reconstruction as speech. |
