Performance limits of coded diversity methods for transmitter antenna arrays

Abstract

Several aspects of the design and optimization of coded multiple-antenna transmission diversity methods for slowly time-varying channels are explored from an information-theoretic perspective. Both optimized vector-coded systems, which can achieve the maximum possible performance, and suboptimal scalar-coded systems, which reduce complexity by exploiting suitably designed linear precoding, are investigated. The achievable rates and associated outage characteristics of these spatial diversity schemes are evaluated and compared, both for the case when temporal diversity is being jointly exploited and for the case when it is not. Complexity and implementation issues more generally are also discussed.

Power-Allocation Policy and Optimized Design of Multiple-Antenna Systems With Imperfect Channel Estimation

“…As is well known, when the multiple-input-multiple-output (MIMO) channel is perfectly estimated by the receiver and this (perfect) estimate is fed back to the transmitter via an ideal link, then the optimal policy for power allocation is the so-called water-filling (WF) one [2], [8], [14], [15], [17].…”

Enhancing Closed-Loop Wireless Systems Through Efficient Feedback Reconstruction

“…It has been shown that the ideal feedback and cophase feedback schemes enhance the (average) received SNR by a factor of M and 1 + (M − 1)π/4, respectively, with respect to the transmit SNR (SNR tx = E s /N 0 ) [13], [22]. This SNR gain is used as a figure of merit in an uncoded system.…”

On a Hybrid Beamforming/Space-Time Coding Scheme

“…When the channel coefficients are fixed and unknown to the transmitter, the capacity of the system in Fig. 1(b) is [1] ( 1) where is defined by (2) with the total average transmitted energy per symbol and the variance of the additive white noise at the receiver.…”