A new ABER approximation of FSO system using PPM–GMSK hybrid modulation scheme under weak turbulence

Abstract

In this paper, free space optical communication system (FSO) employing a hybrid modulation technique called pulse position modulation–Gaussian minimum shift keying (PPM–GMSK) technique, is investigated by considering log–normal as the channel fading statistics under weak turbulence. The analytical average bit error rate (ABER) and closed form expression of the proposed hybrid modulation scheme are derived. Simulation results depict the excellent agreement of the derived closed form expression with those obtained using Gauss–Hermite approximation and with the Monte Carlo simulations.