Hybrid FSO-RF Turbulent Link Performance under Misalignment Aperture Error

Abstract

A novel hybrid Free Space Optics (FSO)/Radio Frequency (RF) model is proposed which is based on the single decision threshold feedback bit switching technique. The FSO and proposed hybrid FSO-RF links performance are investigated under strong turbulence and misalignment aperture error in terms of the average symbol error rate (ASER) and outage probability. The FSO-RF link is preferred in this work over the normal FSO link due to ease in switching among the link established with the help of decision threshold during failure of FSO link. In this proposed hybrid model, Gamma-Gamma distribution is considered as free-space optical turbulence channel and Nakagami-m model is for RF link. The analytical expressions for the outage probability and ASER have been derived for various Intensity Modulation - M-phase shift keying (PSK) schemes. A performance comparative study is reported for FSO link and hybrid FSO-RF link. The obtained result indicates the enhanced system performance with the hybrid model whereas the obtained results are validated through MC simulations and results are found in good agreement.