Doppler receiver for Cassini radio science experiments

Abstract

The Ka band tracking capability of the Cassini spacecraft allows for greater accuracy in most Radio Science experiments, but can be used only with the Goldstone DSN complex, i.e. for one third of the total time. A digital receiver has been designed to allow receiving the Ka band signal from a generic VLBI antenna. The receiver interfaces with the VLBI receiver and formatter. It records an instantaneous bandwidth from 1 Hz to 125 kHz, with corresponding accuracy of 16 to 8 bits respectively. The receiver is implemented as a VME card and is controlled by a standard VME computer.