On the Fundamentally Asynchronous Nature of Interference in Cooperative Base Station Systems

Cooperative transmission by base stations can significantly improve the spectral efficiency of multiuser, multi-cell multiple input multiple output systems. We show that in such systems the multiuser interference is asynchronous by nature, even when perfect timing-advance mechanisms ensure that the desired signal components arrive synchronously. We establish an accurate mathematical model for the asynchronism, and use it to show that the asynchronism leads to a significant performance degradation of existing linear precoding designs that assumed synchronous interference. We consider three different previously proposed precoding designs, and show how to modify them to effectively mitigate asynchronous interference. ICC 2007 This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include ...

• Type: Conference
• Year: 2007
• Where: ICC
• Authors: Hongyuan Zhang, Neelesh B. Mehta, Andreas F. Molisch, Jin Zhang, Huaiyu Dai
• Keywords: Communications, Electric Research Laboratories, ICC 2007, Mitsubishi Electric Research, Multi-cell Multiple Input