Evolution of Limited-Feedback CoMP Systems from 4G to 5G: CoMP Features and Limited-Feedback Approaches

Coordinated multipoint (CoMP) transmission/reception has been adopted as a key technology to alleviate the intercell interference (ICI) in fourthgeneration (4G) mobile communication. This article reviews the state of the art in limited-feedback CoMP systems research. We first give an overview of recent related work in feedback-based coordinated transmission and then provide a performance analysis of typical feedback schemes and sensitivity to the channel state information (CSI) delay. To back up the discussion, we have validated the benefits of CoMP using field-test results from a CoMP trial network built at the Beijing University of Posts and Telecommunications (BUPT) campus. Furthermore, since mobile systems evolving to fifth generation (5G) have to bear a huge quantity of irregularly distributed wireless data traffic, cooperative communication will be more widely applied not only to address the ICI but also to improve the system resource utilization and data rate. We summarize the recent trend on 5G network architectures enabling the novel CoMP features, and we discuss the potential evolution directions of limited-feedback approaches motivated by CoMP development toward future 5G networks.