Title :
Degrees of freedom of time-correlated broadcast channels with delayed CSIT: The MIMO case
Author :
Xinping Yi ; Gesbert, David ; Sheng Yang ; Kobayashi, Masato
Author_Institution :
EURECOM, Sophia-Antipolis, France
Abstract :
The two-user Multiple-Input Multiple-Output (MIMO) broadcast channel (BC) with arbitrary antenna configuration is considered, in which the transmitter obtains (i) delayed channel state information (CSI) from a latency-prone feedback channel as well as (ii) imperfect current CSI, e.g., from prediction based on these past channel samples. The degrees of freedom (DoF) region under such a setting is fully characterized as a function of a prediction quality exponent. This work extends prior work, previously limited to MISO, to fully general antenna settings. An intriguing by-product of our results is to reveal the benefits of dealing with an asymmetric multi-user MIMO configuration (i.e., one in which terminals do not have the same number of antennas) in the case of non-perfect CSIT (e.g., caused by feedback delays or limited preciseness).
Keywords :
MIMO communication; antennas; broadcast channels; feedback; radio transmitters; arbitrary antenna configuration; asymmetric multiuser MIMO configuration; degrees of freedom; delayed CSIT; delayed channel state information; latency-prone feedback channel; time-correlated broadcast channels; transmitter; Decoding; Interference; MIMO; Receiving antennas;
Conference_Titel :
Information Theory Proceedings (ISIT), 2013 IEEE International Symposium on
Conference_Location :
Istanbul
DOI :
10.1109/ISIT.2013.6620374