Exploiting Channel Correlations - Simple Interference Alignment Schemes with No CSIT

We explore a few selected multiuser communication problems where the possibility of interference alignment, and consequently, the total number of degrees of freedom (DoF) with channel uncertainty at the transmitters are unknown. These problems share the common property that in each case the best known outer bounds are essentially robust to channel uncertainty and represent the outcome with interference alignment, but the best inner bounds -- in some cases conjectured to be optimal -- predict a total collapse of DoF, thus indicating the infeasibility of interference alignment under channel uncertainty at transmitters. Our main contribution is to show that even with no knowledge of channel coefficient values at the transmitters, the knowledge of the channels' correlation structure can be exploited to achieve interference alignment.

[1]  Giuseppe Caire,et al.  On achievable rates in a multi-antenna broadcast downlink , 2000 .

[2]  Syed Ali Jafar,et al.  Too much mobility limits the capacity of wireless ad-hoc networks , 2005, IEEE Global Telecommunications Conference, 2004. GLOBECOM '04..

[3]  David Tse,et al.  Fundamentals of Wireless Communication , 2005 .

[4]  Kareem E. Baddour,et al.  Autoregressive modeling for fading channel simulation , 2005, IEEE Transactions on Wireless Communications.

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

[6]  Shlomo Shamai,et al.  On the Capacity of Fading MIMO Broadcast Channels with Imperfect Transmitter Side-Information , 2006, ArXiv.

[7]  S.A. Jafar,et al.  Degrees of Freedom of Wireless Networks - What a Difference Delay Makes , 2007, 2007 Conference Record of the Forty-First Asilomar Conference on Signals, Systems and Computers.

[8]  Shlomo Shamai,et al.  On the Compound MIMO Broadcast Channel , 2007 .

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

[10]  Sriram Vishwanath,et al.  Capacity of Symmetric K-User Gaussian Very Strong Interference Channels , 2008, IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference.

[11]  Changho Suh,et al.  Interference Alignment for Cellular Networks , 2008, 2008 46th Annual Allerton Conference on Communication, Control, and Computing.

[12]  Shlomo Shamai,et al.  Degrees of Freedom Region of the MIMO $X$ Channel , 2008, IEEE Transactions on Information Theory.

[13]  S. Jafar,et al.  Degrees of freedom of the K user MIMO interference channel , 2008, 2008 42nd Asilomar Conference on Signals, Systems and Computers.

[14]  Syed Ali Jafar,et al.  Interference Alignment and Degrees of Freedom of the $K$-User Interference Channel , 2008, IEEE Transactions on Information Theory.

[15]  Shlomo Shamai,et al.  On Degrees of Freedom Region of MIMO Networks without CSIT , 2009, ArXiv.

[16]  Amir K. Khandani,et al.  Real Interference Alignment with Real Numbers , 2009, ArXiv.

[17]  Erik Ordentlich,et al.  On the Degrees-of-Freedom of the K-user Gaussian interference channel , 2009, 2009 IEEE International Symposium on Information Theory.

[18]  Namyoon Lee,et al.  A novel signaling for communication on MIMO Y channel: Signal space alignment for network coding , 2009, 2009 IEEE International Symposium on Information Theory.

[19]  Sae-Young Chung,et al.  Capacity of a class of multi-source relay networks , 2009, 2009 Information Theory and Applications Workshop.

[20]  Multiuser MIMO degrees of freedom with no CSIT , 2009 .

[21]  Syed Ali Jafar,et al.  Interference Alignment With Asymmetric Complex Signaling—Settling the Høst-Madsen–Nosratinia Conjecture , 2009, IEEE Transactions on Information Theory.

[22]  Tsachy Weissman,et al.  Error Exponents for the Gaussian Channel With Active Noisy Feedback , 2011, IEEE Transactions on Information Theory.

[23]  Roy D. Yates,et al.  Interference Alignment for Line-of-Sight Channels , 2008, IEEE Transactions on Information Theory.

[24]  Sriram Vishwanath,et al.  Ergodic Interference Alignment , 2009, IEEE Transactions on Information Theory.