2012/08/31 by Kaniska Mohanty, Mohanty, Kaniska, Chinmay S. Vaze +3
Engineering · #Advanced MIMO Systems Optimization #Advanced Wireless Communication Techniques #FOS: Computer and information sciences #Information Theory (cs.IT) #Wireless Communication Security Techniques
paper · pdf · doi:10.48550/arxiv.1209.0047
openalex publication_date 2012/08/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The degrees of freedom (DoF) region of the two-user MIMO (multiple-input\nmultiple-output) interference channel is established under a new model termed\nas hybrid CSIT. In this model, one transmitter has delayed channel state\ninformation (CSI) and the other transmitter has instantaneous CSIT, of incoming\nchannel matrices at the respective unpaired receivers, and neither transmitter\nhas any knowledge of the incoming channel matrices of its respective paired\nreceiver. The DoF region for hybrid CSIT, and consequently that of\n2\×2\×35 CSIT models, is completely characterized, and a new\nachievable scheme based on a combination of transmit beamforming and\nretrospective interference alignment is developed. Conditions are obtained on\nthe numbers of antennas at each of the four terminals such that the DoF region\nunder hybrid CSIT is equal to that under (a) global and instantaneous CSIT and\n(b) global and delayed CSIT, with the remaining cases resulting in a DoF region\nwith hybrid CSIT that lies somewhere in between the DoF regions under the\ninstantaneous and delayed CSIT settings. Further synergistic benefits accruing\nfrom switching between the two hybrid CSIT models are also explored.\n