Interference Alignment with Limited Feedback on Two-cell Interfering MIMO-MAC
Namyoon Lee, Wonjae Shin,
Robert W. Heath, Jr. and Bruno Clerckx
Proceedings of the IEEE International Symposium on Wireless Communication Systems (ISWCS), Paris, France, pp. 566 - 570, August 28-31, 2012. (Invited)
In this paper, we consider a two-cell interfering
multiple-input multiple-output multiple access channel (MIMOMAC). We ?rst investigate the multiplexing gain of such channel
when users have perfect channel state information at the transmitter (CSIT) by exploiting an interference alignment scheme.
In addition, we propose a quantized transmit beamforming vector feedback method for the interference alignment in the
limited feedback system. On the basis of the proposed feedback framework, we analyze the rate gap loss and it is shown that
in order to keep the same multiplexing gain with the case of perfect CSIT, the number of feedback bits per receiver should
be increased linearly with the SNR in dB scale. Throughout the simulation results, it is shown that the sum-rate performance
coincides with the derived results.
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