摘要 |
In a direct-conversion type orthogonal demodulator used in a multi-band receiver, influence to signal-receiving characteristics of the receiver, caused by DC offset drift produced when a band is switched to another, is reduced. In a multi-band receiver including a plurality of orthogonal demodulators each carrying out orthogonal demodulation for each of a plurality of band inputs, a switch which selects one of outputs transmitted from the orthogonal demodulators in accordance with a band-switching control signal and a high pass filter receiving an output transmitted from the switch, a cut-off frequency of the high pass filter is raised when a band is switched to another, to thereby shorten a convergent time of DC offset drift included in an output signal.
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