Coded Modulation With Mismatched CSIT Over MIMO Block-Fading Channels

• Published in: IEEE transactions on information theory 2010-11, Vol.56 (11), p.5631-5640
• Main Authors: Kim, Tùng T, Nguyen, Khoa D, Guillén i Fàbregas, Albert
• Format: Article
• Language: English
• Subjects: Algorithms; Applied sciences; Blocking; Channels; Coded modulation; Codes; Decay; Detection, estimation, filtering, equalization, prediction; discrete input; diversity methods; Exact sciences and technology; Exponents; Fading; Information systems; Information theory; Information, signal and communications theory; Input output analysis; large-deviation analysis; Mathematical models; MIMO; MIMO systems; Modulation, demodulation; Noise measurement; Normal distribution; Outages; Power control; Signal and communications theory; Signal to noise ratio; Signal, noise; singleton bound; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Transmitters
• ISSN: 0018-9448; 1557-9654
• DOI: 10.1109/TIT.2010.2070250

Reliable communication over delay-constrained multiple-input multiple-output (MIMO) block-fading channels with discrete inputs and mismatched (imperfect) channel state information at the transmitter (CSIT) is studied. The CSIT mismatch is modeled as Gaussian random variables, whose variances decay as a power of the signal-to-noise ratio (SNR). A special focus is placed on the large-SNR decay of the error and outage probabilities when power control with long-term power constraints is used. Without explicitly characterizing the corresponding power allocation algorithms, we derive the outage exponent as a function of the system parameters, including the CSIT noise variance exponent and the exponent of the peak power constraint. It is shown that CSIT, even if noisy, is always beneficial and leads to important gains in terms of exponents.