| 摘要 |
PROBLEM TO BE SOLVED: To simplify a decoding part and to perform variable rate transmissions in a frame unit up to several Mbps by one channel. SOLUTION: On a transmission side, input signals equal to or less than a reference transmission speed are defined as a reference transmission speed by a symbol repetition part 115 and transmitted by using a spread code sequence for which PN1 and PN2 are switched according to a switching pattern corresponding to the transmission speed of the input signals 111. After received signals are distributed and multiplied with random code sequences PN1 and PN2 for respective sequences on a reception side, a transmission speed is estimated without depending on the break of information signals in a transmission speed estimation part 123. The above processing is repeated for plural times within a range not exceeding a frame length and then, the transmission speed is judged in a transmission speed judgement means 125. Based on the judged result, decoding is performed in decoding part 131. |
