An X-band radio channel model for propagation through the solar corona

Spacecraft communication systems operating at X-band are strongly affected when the propagation path passes close to the sun (which can be characterised by the Sun-Earth-Probe, SEP, angle). In this paper, a channel model that can generate a time-series of signal amplitude and phase, and hence the signal in-phase and quadrature values, is presented. For X-band, the channel model reproduces the observations well for SEP>0.8°. While the model has not been experimentally validated at SEP angles below 0.8°, the behaviour is consistent with measurements reported in the literature and is therefore likely to be suitable for use, with caution, in that region too.