| 摘要 |
PURPOSE:To prevent an error from being enlarged by bringing a demodulation symbol train to code conversion in accordance with an estimated symbol difference between transmission and reception and reproducing reception data. CONSTITUTION:This demodulator is constituted of a PSK modulating signal receiver 43, a demodulator 47, a difference computing element 49, a frame detector 55, a symbol difference estimating part 61, and a code converter 69. In this state, by receiving a signal sent out by a frame signal modulating method determined between transmission and reception in advance, and bringing the reception signal to a difference operation in a reception side, they become the same irrespective of a symbol difference, therefore, a frame signal is detected from the symbol after the difference operation. On the other hand, a symbol difference between transmission and reception is estimated from the reception symbol of a part which is not brought to the difference operation in a transmission side in the detected frame signal, and by bringing a demodulation symbol train to the code conversion in accordance with this symbol difference, the reception data is reproduced. In such a manner, even when the data is received erroneously, it can be received with the high quality without enlarging the error. |
