Patent ID: 8238858
Filing Date: 2012-08-07
Classification: H04B,H04L

Abstract:
1. A communication device including: a plurality of orthogonal demodulators each covering each of a plurality of frequency bands, wherein predetermined measurement is carried out in a transmission gap period in which a part of a frame in one of said frequency bands is ceased to be transmitted, for the other among said frequency bands, and data in said transmission gap period is transmitted; a switch which is electrically connected to outputs of the plurality of orthogonal demodulators, which switches among the outputs to select one of the outputs in accordance with a band-switching control signal, and which transmits the selected output indicating a frequency band to be used, wherein the selected output passes through the switch; a convergent-time shortening unit for, when said one of said frequency bands is switched by the switch to said other among said frequency bands, shortening a convergent time of DC offset drift caused by switching one of said orthogonal demodulators to the other; and a DC short-circuit unit for, when said one of said frequency bands is switched to said other among said frequency bands, DC short-circuiting an output transmitted from an orthogonal demodulator associated with said one of said frequency bands and an output transmitted from an orthogonal demodulator associated with said other among said frequency bands to each other based on said band-switching control signal for a predetermined period of time.