Article

Diversity-Integration Tradeoffs in MIMO Detection

DIET, Univ. degli Studi di Napoli Federico II, Naples
IEEE Transactions on Signal Processing (impact factor: 2.63). 11/2008; DOI:10.1109/TSP.2008.928693 pp.5051 - 5061
Source: IEEE Xplore

ABSTRACT In this paper, a multiple-input multiple-output (MIMO) detection problem is considered. At first, we derive the generalized likelihood ratio test (GLRT) for arbitrary transmitted signals and arbitrary time-correlation of the disturbance. Then, we investigate design criteria for the transmitted waveforms in both power-unlimited and power-limited systems and we derive closed-form formulas for the probability of false alarm and the detection probability. Finally, we study the interplay among the rank of the optimized space-time code (i.e., the number of linearly independent transmitted waveforms), the number of transmit diversity paths generated in the signal space, and the amount of energy integrated along each path. The results confirm that there is an inherent tradeoff between diversity and integration, and that no uniformly optimum waveform design strategy exists.

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Keywords

arbitrary
 
arbitrary time-correlation
 
design criteria
 
detection probability
 
false alarm
 
generalized likelihood ratio test
 
inherent tradeoff
 
linearly independent
 
optimized space-time code
 
power-limited systems
 
signal space
 
signals
 
transmit diversity paths
 
transmitted waveforms
 
uniformly optimum waveform design strategy
 
waveforms
 

A. De Maio