TRANSMITTER, RECEIVER, COMMUNICATION SYSTEM, TRANSMITTING METHOD, RECEIVING METHOD AND COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To improve the efficiency of information transmission by inserting a pilot signal for estimating a transmission path to the output signal of a mapping circuit and orthogonally converting a transmission signal with an added pilot signal so as to apply a transmission line estimating method suited to it in accordance with the characteristics of information to be transmitted. SOLUTION: A symbol stream generated by a symbol mapping circuit 203 is inputted to a differential modulation/pilot adding circuit 204. The circuit 204 selects a differential modulation system with respect to the inputted symbol stream in accordance with the characteristics of transmission data such as the data quantity of a packet in the case of packet communication, the tolerance of an error rate corresponding to the importance of transmitting information or inserts a pilot symbol for estimating a transmission path. This circuit 204 generates a transmission symbol stream. Then, a signal randomizing circuit 205 executes orthogonal conversion, etc., to the transmission symbol stream.