COMMUNICATION DEVICE, MULTI-BAND RECEPTION DEVICE, AND RECEPTION DEVICE

摘要

In an orthogonal demodulator of direct conversion method used in a multi-band reception device, it is possible to reduce the affect of DC offset drift generated during band switching to reception characteristic. The multi-band reception device includes: a plurality of orthogonal demodulators (5, 6) orthogonally demodulating a plurality of band inputs; a selector switch for selecting one of the plurality of orthogonal demodulators by a band switching control signal (15): and a broadband pass filter (8) for receiving the output of the selector switch (7) as an input. In the multi-band reception device, upon band switching, control is performed to increase the cut-off frequency of the broadband pass filter (8) so as to reduce the convergence time of the DC offset drift contained in the output signal.