DocumentCode :
1051352
Title :
The MIMO ARQ Channel: Diversity–Multiplexing–Delay Tradeoff
Author :
El Gamal, Hesham ; Caire, Giuseppe ; Damen, Mohamed Oussama
Author_Institution :
Electr. & Comput. Eng. Dept., Ohio State Univ., Columbus, OH
Volume :
52
Issue :
8
fYear :
2006
Firstpage :
3601
Lastpage :
3621
Abstract :
In this paper, the fundamental performance tradeoff of the delay-limited multiple-input multiple-output (MIMO) automatic retransmission request (ARQ) channel is explored. In particular, we extend the diversity-multiplexing tradeoff investigated by Zheng and Tse in standard delay-limited MIMO channels with coherent detection to the ARQ scenario. We establish the three-dimensional tradeoff between reliability (i.e., diversity), throughput (i.e., multiplexing gain), and delay (i.e., maximum number of retransmissions). This tradeoff quantifies the ARQ diversity gain obtained by leveraging the retransmission delay to enhance the reliability for a given multiplexing gain. Interestingly, ARQ diversity appears even in long-term static channels where all the retransmissions take place in the same channel state. Furthermore, by relaxing the input power constraint allowing variable power levels in different retransmissions, we show that power control can be used to dramatically increase the diversity advantage. Our analysis reveals some important insights on the benefits of ARQ in slow-fading MIMO channels. In particular, we show that 1) allowing for a sufficiently large retransmission delay results in an almost flat diversity-multiplexing tradeoff, and hence, renders operating at high multiplexing gain more advantageous; 2) MIMO ARQ channels quickly approach the ergodic limit when power control is employed. Finally, we complement our information-theoretic analysis with an incremental redundancy lattice space-time (IR-LAST) coding scheme which is shown, through a random coding argument, to achieve the optimal tradeoff(s). An integral component of the optimal IR-LAST coding scheme is a list decoder, based on the minimum mean-square error (MMSE) lattice decoding principle, for joint error detection and correction. Throughout the paper, our theoretical claims are validated by numerical results
Keywords :
MIMO systems; automatic repeat request; channel coding; decoding; diversity reception; error correction codes; error detection codes; fading channels; least mean squares methods; multiplexing; power control; random codes; space-time codes; IR-LAST coding scheme; MIMO ARQ channel; MMSE; automatic retransmission request; coherent detection; diversity-multiplexing delay tradeoff; error correction; fading channel; incremental redundancy lattice space-time; information-theoretic analysis; joint error detection; list decoder; minimum mean-square error; multiple-input multiple-output; power control; random coding; reliability; Automatic repeat request; Decoding; Delay; Diversity methods; Information analysis; Lattices; MIMO; Power control; Redundancy; Throughput; Automatic retransmission request (ARQ) protection; diversity–multiplexing tradeoff; incremental redundancy coding; lattice coding; multiple-input multiple-output (MIMO) channels; space–time coding;
fLanguage :
English
Journal_Title :
Information Theory, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9448
Type :
jour
DOI :
10.1109/TIT.2006.878173
Filename :
1661837
Link To Document :
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