TR2007-030

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


    •  Zhang, H.; Mehta, N.B.; Molisch, A.F.; Zhang, J.; Dai, H., "On the Fundamentally Asynchronous Nature of Interference in Cooperative Base Station Systems", IEEE International Conference on Communications (ICC), June 2007.
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      • @inproceedings{Zhang2007jun,
      • author = {Zhang, H. and Mehta, N.B. and Molisch, A.F. and Zhang, J. and Dai, H.},
      • title = {On the Fundamentally Asynchronous Nature of Interference in Cooperative Base Station Systems},
      • booktitle = {IEEE International Conference on Communications (ICC)},
      • year = 2007,
      • month = jun,
      • url = {http://www.merl.com/publications/TR2007-030}
      • }
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  • Research Areas:

    Electronics & Communications, Wireless Communications


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.