| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce interference to adjacent cells while maintaining an SNR at a terminal position, while keeping a value equivalent to the one when transmission diversity is applied, when radio wave arrival ranges from a base station with a plurality of transmission antennas are different. <P>SOLUTION: The base station includes a first antenna which transmits radio waves at a first tilt angle; and a second antenna which transmits the radio wave at a second tilt angle different from the first tilt angle. When propagation distance differs in the plurality of antennas, not only the transmission diversity gain is not obtained but also the interference with the adjacent area occurs. In such a case, the throughput of a terminal in a corresponding area is raised more by transmission using one antenna with a short propagation distance with less interference with the adjacent area. For example, a control part switches transmission from two-antenna transmission to one-antenna transmission, when difference of reception quality is smaller than a predetermined reference, on the basis of reception quality of each signal from a self-base station to be measured at the terminal and the reception quality of a signal from the adjacent base station adjacent to the self-base station. <P>COPYRIGHT: (C)2011,JPO&INPIT |
