The Multiplexing Gain of MIMO X-Channels with Partial Transmit Side-Information

In this paper, we obtain the scaling laws of the sum-rate capacity of a MIMO X-channel, a 2 independent sender, 2 independent receiver channel with messages from each transmitter to each receiver, at high signal to noise ratios (SNR). The X-channel has sparked recent interest in the context of cooperative networks and it encompasses the interference, multiple access, and broadcast channels as special cases. Here, we consider the case with partially cooperative transmitters in which asymmetric side-information (in the form of a codeword) is available at one of the transmitters. It is proved that when there are M antennas at all four nodes, the sum-rate scales like 2M log SNR which is in sharp contrast to lceillfloor4M/3rfloor, 4M/3rceil log SNR for non-cooperative X-channels [M. Maddah-Ali et al., 2006], [S.A. Jafar]. This further proves that, in terms of sum-rate scaling at high SNR, partial side-information at one of the transmitters and full side-information at both transmitters are equivalent in the MIMO X-channel.

[1]  Te Sun Han,et al.  A new achievable rate region for the interference channel , 1981, IEEE Trans. Inf. Theory.

[2]  Shlomo Shamai,et al.  The capacity region of the Gaussian MIMO broadcast channel , 2004, International Symposium onInformation Theory, 2004. ISIT 2004. Proceedings..

[3]  Patrick Mitran,et al.  Achievable rates in cognitive radio channels , 2006, IEEE Transactions on Information Theory.

[4]  Amir K. Khandani,et al.  Communication Over MIMO X Channels: Interference Alignment, Decomposition, and Performance Analysis , 2008, IEEE Transactions on Information Theory.

[5]  Vahid Tarokh,et al.  On the degrees-of-freedom of the MIMO interference channel , 2008, 2008 42nd Annual Conference on Information Sciences and Systems.

[6]  Syed Ali Jafar,et al.  I T ] 1 2 Se p 20 06 Degrees of Freedom on the MIMO X Channel-Optimality of Zero Forcing and the MMK Scheme , 2008 .

[7]  R. Gallager.  Information Theory and Reliable Communication , 1968 .

[8]  Mohammad Ali Maddah-Ali,et al.  Communication over MIMO X Channel: Signalling and Performance Analysis , 2006 .

[9]  Aydano B. Carleial,et al.  Interference channels , 1978, IEEE Trans. Inf. Theory.

[10]  Wei Wu,et al.  On the Capacity of Interference Channels with Degraded Message sets , 2006, ArXiv.

[11]  Max H. M. Costa,et al.  Writing on dirty paper , 1983, IEEE Trans. Inf. Theory.

[12]  Shlomo Shamai,et al.  On the achievable throughput of a multiantenna Gaussian broadcast channel , 2003, IEEE Transactions on Information Theory.

[13]  Aria Nosratinia,et al.  The multiplexing gain of wireless networks , 2005, Proceedings. International Symposium on Information Theory, 2005. ISIT 2005..

[14]  D. A. Bell,et al.  Information Theory and Reliable Communication , 1969 .

[15]  Amir K. Khandani,et al.  Signaling over MIMO Multi-Base Systems: Combination of Multi-Access and Broadcast Schemes , 2006, 2006 IEEE International Symposium on Information Theory.

[16]  Thomas M. Cover,et al.  Elements of Information Theory , 2005 .