Outage Analysis of Practical FSO/RF Hybrid System With Adaptive Combining

• Published in: IEEE communications letters Vol. 19; no. 8; pp. 1366 - 1369
• Main Authors: Rakia, Tamer, Hong-Chuan Yang, Alouini, Mohamed-Slim, Gebali, Fayez
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2015; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Diversity reception; Gamma-Gamma atmospheric turbulence; Hybrid FSO/RF; Hybrid power systems; MRC combining; Nakagami-m fading model; Optical attenuators; Optical receivers; Optical wireless; Outage probability; Radio frequency; Signal to noise ratio; gamma-gamma atmospheric turbulence; outage probability; Hybrid FSO/RF; MRC combining; Nakagami- m fading model
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/LCOMM.2015.2443771

Hybrid free-space optical (FSO)/radio-frequency (RF) systems have emerged as a promising solution for high-data-rate wireless transmission. We present and analyze a transmission scheme for the hybrid FSO/RF communication system based on adaptive combining. Specifically, only FSO link is active as long as the instantaneous signal-to-noise ratio (SNR) at the FSO receiver is above a certain threshold level. When it falls below this threshold level, the RF link is activated along with the FSO link and the signals from the two links are combined at the receiver using a dual-branch maximal ratio combiner. Novel analytical expression for the cumulative distribution function (CDF) of the received SNR for the proposed hybrid system is obtained. This CDF expression is used to study the system outage performance. Numerical examples are presented to compare the outage performance of the proposed hybrid FSO/RF system with that of the FSO-only and RF-only systems.