Spatial Multiplexing Architectures with Jointly Designed Rate-Tailoring and Ordered BLAST Decoding - Part I: Diversity-Multiplex

Abstract-- The V-BLAST (vertical Bell Labs layered Space-Time) architecture involves independent coding/decoding per antenna (layer) with equal rate and power per antenna and a fixed order of nulling/canceling decoding but is known to suffer from poor performance; for example, in a multi-input multi-output (MIMO) Rayleigh fading channel with Mt transmit and Mr receive antennas (Mr Mt), the diversity-multiplexing gain (D-M) tradeoff is just (Mr -Mt +1)(1-r/Mt) for r [0, Mt]. There are two remedies available, namely, (i) channel-dependent ordered decoding at the receiver and (ii) allocation of rates and powers across the transmit antennas. However, the former doesn't improve the D-M tradeoff curve and while the latter does (with maximum diversity gain Mr and maximum multiplexing gain Mt), its tradeoff curve is still significantly inferior compared to the D-M tradeoff curve of the optimum (unconstrained) MIMO architecture. In this two-part paper, it is shown that a dramatically bett...

• Type: Journal
• Year: 2008
• Where: TWC
• Authors: Yi Jiang, Mahesh K. Varanasi
• Keywords: Better D-m Tradeoff, D-M Tradeoff, D-M Tradeoff Curve, TWC 2008