Abstract: Multiple-input multiple-output(MIMO) technology can be used to increase the amount of diversity or the number of degrees of freedom.Previous works focus much on maximizing one of the gains,and this makes it difficult to make full use of the performance of multiple antennas system.Aiming at these problems,a novel diversity and multiplexing decision algorithm is proposed based on adaptive link technique.Taking bit error rate(BER) as decision criterion,the proposed algorithm achieves adaptive bit and power allocation according to real-time channel state information(CSI),and the system mode is dynamically adjusted based on limited feedback bits from receiver.To reduce the computational complexity,the proposed algorithm gives out the sub-optimal decision criterion utilizing the approximate bound of received signal-to-noise ratio(SNR) based on CSI.The proposed algorithm can obtain the diversity and multiplexing gains simultaneously,improves the system reliability and transmission rate,has lower computational complexity,and provides excellent robustness against channel fading.Simulation results show that comparing with the traditional algorithms the proposed algorithm has a better performance and meets the real-time and rapidity requirements of the practical communication system.