A Single Detector Versus an Array of Detectors Receiver in Free-Space
Optical Communications: A Performance Comparison
Abstract
Free-space optical (FSO) communications is an important technology that
will be used for supporting high data-rates in the backhaul of next
generation of wireless communication networks. In this paper, we have
compared the probability of error performance of two types of receivers
used in FSO today: a receiver based on a single detector, and a receiver
based on an array of detectors. The performance of these two receivers
is compared for a number of fusion algorithms for an array of detectors
such as equal gain combiner (EGC), selection combiner (SC), switched
combiner (SWC) and the maximal ratio combiner (MRC). From this study, we
conclude that even though the array of detectors adds more noise in the
sufficient statistic by virtue of large number of detectors, using more
computationally expensive fusion algorithms (such as SC and MRC) can
help us achieve a superior probability of error performance as opposed
to a single-detector receiver for practical channel conditions.