| 摘要 |
PROBLEM TO BE SOLVED: To make it unnecessary to transmit a pilot symbol in addition to a start symbol for estimating propagation path characteristics, and to efficiently estimate the characteristics by operating envelope detection separately from the delay detection of an inverse spread signal, and estimating the propagation characteristics according to the detected result. SOLUTION: A start symbol spread spectrum by one spreading code is transmitted prior to signals (data symbol) transmitted in parallel. At the time of receiving the start symbol, orthogonal I signal and Q signal are inputted to passive correctors 10 and 11, and a correlation value is outputted from the passive correlator 10 matched with the spreading code of a transmission channel. The output signal of the passive correlator 10 is supplied to a delay detector 20, and also supplied to a delay detector 21 according to the switching of switches 1 and 2. The output signal of the passive corrector 10 is also inputted to an envelope detector 70, and envelop detection is operated. Then, an outputted envelope signal is supplied to a propagation path estimator 40, and used for estimating propagation characteristics. |
