Mobile terminal, radio communication apparatus and radio communication method

A mobile terminal in a radio communication system that uses multiple antennas to perform transmission to the mobile terminal, comprising:

• a reception quality measurement unit that measures the reception quality of each signal that is transmitted from each antenna and received by the mobile terminal;
• an antenna determination unit that determines a plurality of first antennas forming low correlation with each other based on the reception qualities;
• a multi-dimension correlation calculation unit that calculates multi-dimension correlation between each of the plurality of first antennas and other antennas;
• a low correlation resource selection unit that selects all resources for each of the plurality of first antennas where the multi-dimension correlation is lower than a set value;
• and
• a feedback unit that feeds back data that indicates each of the plurality of first antennas, all of the low correlation resources for each of the plurality of first antennas and the reception qualities to the transmitting side so that it is possible to designate antennas corresponding to the resources of low correlation as second antennas for diversity antennas for each of the plurality of first antennas, and to perform diversity transmission of signals to the mobile terminal using the plurality of first and second antennas.

A radio communication apparatus that uses a plurality of antennas to transmit signals to a mobile terminal, comprising:

• a receiving unit that receives data, from the mobile terminal, identifying one antenna from among the plurality of antennas as a first antenna and identifying all resources where multi-dimension correlation between the first antenna and other antennas of the plurality of antennas is lower than a set value as low correlation resources;
• a scheduler that determines antennas from the other antennas corresponding to the low correlation resources to be second antennas when a communication rate of the first antenna is less than a requested communication rate for real-time communication;
• and
• a diversity transmission unit that uses the first antenna and the second antennas to perform diversity transmission of identical data to the mobile terminal.

A radio communication apparatus that uses a plurality of antennas to transmit signals to a mobile terminal, comprising:

• a receiving unit that receives data, from the mobile terminal, identifying two or more antennas from among the plurality of antennas as of first antennas and identifying all resources where multi-dimension correlation between each first antenna and other antennas of the plurality of antennas is lower than a set value;
• a scheduler that selects antennas from among the first antennas so that the total communication rate of the selected first antennas is larger than a requested communication rate in real-time communication;
• and
• a transmission unit that transmits identical data from the selected first antennas.

A radio communication method in a radio communication system in which a transmitting side uses multiple antennas to transmit signals to a mobile terminal, comprising:

• measuring the reception quality of each signal that is transmitted from each antenna and received by the mobile terminal;
• determining a first antenna based on the reception qualities in real-time communication;
• calculating multi-dimension correlation between the first antenna and other antennas;
• selecting all resources where the multi-dimension correlation is lower than a set value;
• feeding back data indicating the first antenna, all of the low correlation resources and reception qualities to the transmitting side;
• and
• designating antennas corresponding to the resources of low correlation as second antennas that are candidates for diversity antennas, and performing diversity transmission of signals to the mobile terminal using the first and second antennas.

A radio communication method in a radio communication system that uses multiple antennas to perform MIMO transmission to a mobile terminal, comprising:

• measuring the reception quality of each signal that is transmitted from each antenna and received by the mobile terminal;
• determining a plurality of first antennas corresponding to low correlation with each other based on the reception qualities;
• calculating multi-dimension correlation between each first antenna and other antennas;
• selecting all resources for each of the plurality of first antennas where the multi-dimension correlation is lower than a set value;
• feeding back data that indicates each of the plurality of first antennas, all of the low correlation resources for each of the first antennas and the reception qualities to the transmitting side;
• and
• transmitting identical data from at least the plurality of first antennas to the mobile terminal.