2009/07/14 by Pedro Coronel, Helmut Bölcskei, Coronel, Pedro +1
Computer Science · Engineering · #Advanced MIMO Systems Optimization #Advanced Wireless Communication Techniques #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT)
paper · pdf · doi:10.48550/arxiv.0907.2391
openalex publication_date 2009/07/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We establish the optimal diversity-multiplexing (DM) tradeoff of coherent time, frequency, and time-frequency selective-fading multiple-input multiple-output (MIMO) channels and provide a code design criterion for DM tradeoff optimality. Our results are based on the new concept of the "Jensen channel" associated to a given selective-fading MIMO channel. While the original problem seems analytically intractable due to the mutual information between channel input and output being a sum of correlated random variables, the Jensen channel is equivalent to the original channel in the sense of the DM tradeoff and lends itself nicely to analytical treatment. We formulate a systematic procedure for designing DM tradeoff optimal codes for general selective-fading MIMO channels by demonstrating that the design problem can be separated into two simpler and independent problems: the design of an inner code, or precoder, adapted to the channel statistics (i.e., the selectivity characteristics) and an outer code independent of the channel statistics. Our results are supported by appealing geometric intuition, first pointed out for the flat-fading case by Zheng and Tse, IEEE Trans. Inf. Theory, 2003.