Patent ID: 6928276

Claim:
A signal-reception circuit which receives radio signals in at least two different frequency bands and outputs the signals to signal processing units, the signal-reception circuit comprising: a main antenna for receiving signals in at least two different frequency bands; a sub-antenna for receiving signals in one of the at least two reception frequency bands of the main antenna, the main antenna and the sub-antenna being coupled to each other; a filter arranged to interrupt the signal in the same frequency band as the reception frequency band of the sub-antenna and arranged on a signal line along which a signal is transmitted from the main antenna to a signal-processing unit, wherein the filter reflection signal in the same frequency band as the reception frequency band of the sub-antenna is induced in the sub-antenna by the antenna coupling, and the composite signal of the induced signal and the reception signal of the sub-antenna is output from the sub-antenna to another signal-processing unit; a phase shifter provided on a signal line between the main antenna and the filter, wherein the phase shifter adjusts the phase of the filter reflection signal so that the signal induced in the sub-antenna is put substantially in phase with the reception signal of the sub-antenna to improve the level of the signal to be transmitted from the sub-antenna to the signal-processing unit.