| 摘要 |
<p>When a signal requesting new data transmission is input, transmission signal switching section 104 outputs the output signal from error correction coding section 102 to modulation section 106, and, when a signal requesting data retransmission is input, outputs the signal stored in buffer 103 to modulation section 106. When the signal requesting new data transmission is input, modulation scheme determining section 105 controls modulation section 106 in such a way as to perform modulation using a modulation scheme of the maximum rate. When the signal requesting data retransmission is input, modulation scheme determining section 105 controls modulation section 106 in such a way as to perform modulation using a modulation scheme for retransmission. With regard to the method of determining the modulation scheme for retransmission, possible methods may include one that employs the rate obtained by multiplying a maximum rate by a predetermined fixed number (0.5, for instance) and one that employs phase modulation schemes such as BPSK and QPSK on a fixed basis. By this means it is made possible to reduce the number of times retransmission takes place between the transmitter and receiver and thus improve the transmission efficiency. <IMAGE></p> |
