Degrees of freedom of M × N SISO X channel with synergistic alternating CSIT

In this paper, we investigate degrees of freedom (DoF) of the M × N single input single output (SISO) X channel with alternating channel state information at the transmitter (CSIT). It is known that sum DoF of 2-user SISO X channel with synergistic alternating CSIT is the same as the sum DoF of 2-user (M = N = 2) SISO X channel with perfect CSIT [8]. As an extension of the 2-user case, achievable schemes of the M × N SISO X channel with synergistic alternating CSIT are proposed. It is shown that the proposed M × N X channel schemes with synergistic alternating CSIT achieve the sum DoF 2M/(M + 1), which is better than the weighted sum DoF of the conventional schemes for M ≤ N. The DoF of the proposed scheme with M = N = K is strictly better than the best known DoF for the K-user X channel with delayed CSIT.

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

[2]  Amr El-Keyi,et al.  A degrees of freedom-optimal scheme for SISO X channel with synergistic alternating CSIT , 2014, 2014 IEEE International Symposium on Information Theory.

[3]  Mohammad Ali Maddah-Ali,et al.  Completely Stale Transmitter Channel State Information is Still Very Useful , 2010, IEEE Transactions on Information Theory.

[4]  Amir K. Khandani,et al.  On the degrees of freedom of X channel with delayed CSIT , 2011, 2011 IEEE International Symposium on Information Theory Proceedings.

[5]  Amr El-Keyi,et al.  On the Degrees of Freedom of SISO X-networks with Synergistic Alternating Channel State Information at transmitters , 2016, ArXiv.

[6]  Mahesh K. Varanasi,et al.  The Degree-of-Freedom Regions of MIMO Broadcast, Interference, and Cognitive Radio Channels With No CSIT , 2009, IEEE Transactions on Information Theory.

[7]  Bang Chul Jung,et al.  Degrees-of-Freedom Based on Interference Alignment with Imperfect Channel Knowledge , 2011, IEICE Trans. Commun..

[8]  Jeffrey G. Andrews,et al.  MISO Broadcast Channels with Delayed Finite-Rate Feedback: Predict or Observe? , 2011, IEEE Transactions on Wireless Communications.

[9]  Syed Ali Jafar,et al.  Interference Alignment and the Degrees of Freedom of Wireless $X$ Networks , 2009, IEEE Transactions on Information Theory.

[10]  Shlomo Shamai,et al.  On the Synergistic Benefits of Alternating CSIT for the MISO Broadcast Channel , 2013, IEEE Transactions on Information Theory.

[11]  Jaehong Kim,et al.  Degrees of Freedom of $M\times N$ SISO X Channel with Synergistic Alternating CSIT , 2016 .

[12]  David Gesbert,et al.  Precoding Methods for the MISO Broadcast Channel with Delayed CSIT , 2012, IEEE Transactions on Wireless Communications.

[13]  Ming Xiao,et al.  On the achievable degrees of freedom of partially cooperative X networks with delayed CSIT , 2012, 2012 IEEE Global Communications Conference (GLOBECOM).

[14]  Amir K. Khandani,et al.  On the degrees of freedom of MIMO X channel with delayed CSIT , 2011, 2012 IEEE International Symposium on Information Theory Proceedings.

[15]  Amr El-Keyi,et al.  On the Degrees of Freedom of SISO X-Channel with Alternating CSIT , 2014, ArXiv.

[16]  Shlomo Shamai,et al.  On X-channels with feedback and delayed CSI , 2012, 2012 IEEE International Symposium on Information Theory Proceedings.