Optical links between ground stations and geostationary orbit (GEO) satellites suffer from the atmospherically induced phase piston and intensity fluctuations. This aggravates stable signal detection in the uplink scenario. In this work transmitter diversity is studied as a fading mitigation technique in GEO satellite feeder uplinks. A single sideband scheme is used as a spectrally efficient frequency division technique compatible with intensity modulation and direct detection. A spectral efficiency of 0.56 bit/s/Hz with twofold diversity gaining 2.3 dB at BER = 10-3 was obtained by simulation
