Mitigation of scintillation using antenna receive diversity for Ka band satellite signals

The desire for higher data rates and the need for available bandwidth has pushed satellite communications into the Ka band (20-30 GHz). At these higher carrier frequencies the effects of scintillation due to turbulence-induced index of refraction irregularities in the troposphere is known to become more prevalent, particularly on slant paths. Mitigation of scintillation can be very important for certain links such as those operating at a low-margin along a low elevation path in a dry climate, where scintillation, rather than rain, is the key link factor. We will look at mitigating the deleterious scintillation effects on a satellite signal in the Ka band through the use of two receive antennas. This paper quantifies the possible benefits of such a mitigation technique through the use of a multiple phase screen (MPS) simulation model. We will show that in moderate to strong turbulence cases there can be significant diversity gains achieved by combining two receive antennas, and that even in mild turbulence there is often a diversity gain of 0.5 dB, and that MPS simulations are a useful tool for quantifying scintillation effects on Ka-band satellite signals.