摘要 |
<p>A cellular mobile communication system such as a transmission diversity communication device for which calibration of an antenna system can be easily and efficiently carried out with little deterioration of fading characteristics and with saved power when the number of transmission antennas is increased. The transmission diversity communication device is of a closed loop type to receive a common pilot signal transmitted through the antennas at a base station by a mobile station, to transmit a feedback signal determined by analysis to the base station, and to control a downstream transmission signal at the base station according to the feedback information. The antennas are divided into a plurality of groups, and the common pilot signal is always transmitted from an antenna serving as a reference of each group, and the common pilot signal is alternately transmitted with a low frequency from the other antennas.</p> |