RADIO COMMUNICATION SYSTEM

摘要

PURPOSE:To simplify the hardware in a multi-value quadrature amplitude modulation (QAM) system radio communication system by inserting a carrier for regeneration in a prescribed band limit without giving interference to a signal. CONSTITUTION:A band of a modulation signal is limited by a filter and inputted to a modulator. A modulating wave of spectrum having a zero point at a frequency f0+ or -fa appears at an output of the modulator, where the relation of fa=(m/n)fCL exists with a clock frequency fCL. A pilot signal Cr for regenerating carrier is inserted to at least one zero point frequency of an output of the modulator and transmitted. The carrier is regenerated at the receiving side based on the pilot signal Cr and the regenerated clock signal and the result is inputted to a detector 62.