Closed-loop real-time MIMO-OFDM system for adaptive transmissions

This contribution reports the development of a closed-loop MIMO-OFDM system. Requiring no physical connection between the transmitter and receiver stations, for the feedback link, it permits a large flexibility in the experimental investigation of MIMO algorithms with transmit channel state information (CSI) over many propagation scenarios. The analog front ends have been carefully designed for a very good signal quality at high data rates. The hardware and software has been partitioned in such a way that new MIMO processing algorithms using CSI at the transmitter can be easily integrated.