The MIMO communication system can improve the data transmission rate and spectrum efficiency without increasing the bandwidth and power of system. Each transmitting antenna is allocated a single user in the conventional MIMO communication system, which can improve the channel capacity and the number of user through adding the antenna. It equals to allocating different user to different transmitting antenna. For the transmitting antenna, on the one hand, it would increase the system complexity, on the other hand, the fact that only a single user is allocated on each transmitting antenna is a waste of resource. Therefore, multiplexing multiple users on the antenna is the development trend of MIMO system. For this, we put forward an optimal MIMO system of connecting a virtual space-time channel module to transmitter. It can adaptively adjust the parameters of the module through the feedback information, and optimize the wireless channel, and improve the communication quality of system for the same data transmission rate and increase the data transmission rate for the same communication quality of system. The experiment and simulation shows that the improved MIMO system can improve data transmission rate of 50% at least for a 2×2 MIMO system.