The cassini multifrequency link performance during 2002 solar conjunction

Abstract

During the 2002 Cassini solar conjunction the advanced radio frequency system, based on multiple links and devised to perform radio science experiments, has been continuously operated for 30 days. X- and Ka-band data were concurrently acquired at the Goldstone (CA) Deep Space Network complex, the only station with Ka-band uplink and down-link capability. Open Loop data acquired by the radio science receivers have been analyzed to characterize the performance of the Cassini space and ground segments, in terms of phase stability (Allan deviation), plasma effects due to the solar corona and effectiveness of the plasma calibration scheme based on multiple frequency links. The analysis shows that, while the stability of the uncalibrated links degrades as the line-of-sight get closer to the Sun, the Allan deviation of the plasma calibrated frequency residuals has nearly constant values of 1-2x at integration times of 1000 s. This value was previously achieved only near solar oppositions © 2003 IEEE.