Patent ID: 9166658
Filing Date: 2015-10-20
Classification: H04B

Abstract:
1. A wireless communication system, comprising: a base station including a plurality of transmission antennas; and one or more mobile terminals configured to communicate with the base station, wherein: the wireless communication system is configured to operate in accordance with at least a first feedback method and a second feedback method, both of which correspond to channel information of each of the one or more mobile terminals; the first feedback method includes providing feedback information based on a quantized channel and the second feedback method includes providing feedback information in accordance with a selected one of a plurality of predetermined vectors; the feedback information of the first feedback method includes a larger number of bits than a number of bits required by the feedback information of the second feedback method; each of the one or more mobile terminals individually selects one of the first feedback method and the second feedback method based on either the channel information of each of the one or more mobile terminals or a function of each of the one or more mobile terminals; the one or more mobile terminals provide their respective channel information, which corresponds to a communication condition between the one or more mobile terminals and the base station, to the base station through the selected one of the first feedback method and the second feedback method; the base station is configured to receive the channel information from the one or more mobile terminals and to choose a group of the one or more mobile terminals which has selected a same one of the first feedback method and the second feedback method; the base station is configured to perform, based on the received channel information, spatial multiplexing of transmission signals addressed to the group of the one or more mobile terminals; in the second feedback method, the selected one of the plurality of predetermined vectors corresponds to a vector used for precoding selected from candidates determined in advance as known by the base station and the one or more mobile terminals; the first feedback method is employed when a band width is not less than a predetermined threshold value; and the second feedback method is employed when the band width is less than the threshold value.