MODELING THE PDF FOR THE IRRADIANCE OF AN UPLINK BEAM IN THE PRESENCE OF BEAM WANDER

摘要

Recent studies of ground-to-space beam propagation have revealed significant departures from Rytov theory when the beam diameter w_0 is on the order of the atmospheric coherence width r_0. It has been shown that such departures from Rytov theory are primarily a consequence of beam wander and other low-order aberrations. In this paper we discuss modeling of the probability density function (PDF) for uplink beams. In particular, we show how the PDF transitions from lognormal statistics when w_0 / r_0 < < 1 to the negative exponential distribution when w_0 / r_0 > > 1. The most interesting regime is the transition region near w_0 / r_0 = 1, where the statistical behavior of tracked and untracked beams differs significantly.