Patent ID: 7317747

Claim:
A transmitter that transmits a signal to a receiver, comprising: a first transmitting means that transmits the signal using a frame format that is formed by a first pilot signal in which an end portion of a known signal that has been matched in advance with the receiver is reproduced at a front of the first known signal, and by first transmitted binary data in which an end portion of the data is reproduced at a front of the data; a second transmitting means that transmits the signal using a frame format formed by a second pilot signal formed by a second known signal that has been matched in advance with the receiver, and by second transmitted binary data; a selection means that selects one of the first transmitting means and the second transmitting means when the signal is transmitted; a quality information sharing means that shares quality information that relates to the quality of the transmitted signal with the receiver; and a multiplex number deciding means that decides from the quality information shared with the receiver whether or not code division multiplexing is present for the transmitted signal and also decides a number of Walsh multiplex, wherein the selection means selects one of the first transmitting means and the second transmitting means using control information created in accordance with the decision as to whether or not code division multiplexing is present for the transmitted signal and also the number of Walsh multiplex.