| 摘要 |
In a data transmission system, transmission data (Td-I, Td-Q) is modulated based on pi /4-shift QPSK modulation (102) according to two spreading code sequences (SC-I, SC-Q) which is generated according to a chip timing signal (CLK1) in each symbol interval. At a receiving side, the received spread spectrum signal (Rx-I, Rx-Q) is demodulated based on the same pi /4-shift QPSK modulation (403) according to the respective replicas (SC-Ir, SC-Qr) of the spreading code sequences. <IMAGE> |
