Adaptive modulation for cooperative coded systems

Claims a system method and apparatus for power source from at least one candidate object is selected by a partner and relay the information at least a portion of the source transmitting to the destination. The selected depending on the channel state and when the source to the destination the channel quality is poor the source selecting candidate object and power source and partner and relay the modulation mode so as to make the light source of the frame error rate is reduced fer. Otherwise it is source and partner and the relay each of the selecting the source it can improve the throughput of the gain of the modulation mode. This invention can be used to two-phase mobile key controlling it is composed of four phase shift keying bpsk and qpsk state 16 quadrature amplitude modulation qam 16 is composed of the mode of.