Robustness of Reduced Feedback Precoding in Frame-Based MIMO Systems

In order for MIMO systems to function in real applications, factors such as realistic channel responses and frame structures must be incorporated into their design. Limited feedback precoding schemes have recently been introduced to address limitations with feedback overhead. The performance of two techniques is compared when subjected to delays typical in systems employing data frames using channel responses measured in an urban microcell. The results show that feedback approaches based on matching transmission to specific channel state information are less robust to delays in channel information than methods which feed back symbol rate information.