Technique to maintain formation of a parallel transmission line in spatial multiplex transmission

A radio transmission apparatus includes a communication distance measurement unit configured to measure a distance between a plurality of transmission antennas and a plurality of reception antennas, a selection unit configured to select a modulation scheme common to all frequency channels, the modulation scheme satisfying an average value of index values for each of the frequency channels according to a measured distance and satisfying a predetermined desired bit error rate, a transmission signal generation unit configured to separate transmission data, modulate each item of the separated transmission data by the selected common modulation scheme, and output the transmission signals multiplexed by the number of multiplexing indicating the number of the plurality of transmission antennas to be used. A radio reception apparatus includes a demodulation unit configured to demodulate a reception signal by a demodulation scheme corresponding to the modulation scheme to generate reception data.