A radio communication apparatus having maximized channel capacity, and a method thereof, preferably includes a transmitter having a plurality of transmitting antennae, wherein each transmitting antenna transmits on a channel using a transmission power that is allocated and a base-band signal that is modulated according to a feedback signal from a receiver. The feedback signal is preferably derived in the receiver using an algorithm that analyzes and processes a previously received signal from the plurality of transmitting antennae. Only information on the amount of transmission power to be allocated to a first transmitting antenna from the plurality of transmitting antennae is fed back. Therefore, the channel capacity may be maximized while minimizing the amount of information in a feedback signal. Further, decoupling conversion is not required, thereby reducing the size and cost of manufacturing hardware.