Cassini Spacecraft-DSN Communications, Handling Anomalous Link Conditions, and Complete Loss-of-Spacecraft Signal
Paula S. Morgan · InTech eBooks · 2018
Once spacecraft are launched, it is impossible for engineers to physically repair anything that breaks onboard the vehicle. Instead, remote solutions must be employed to address spacecraft anomalies and fault conditions. To achieve this goal, telemetered data from the spacecraft are collected and assess by ground personnel to resolve problems. However, if the ground-to-spacecraft communication system breaks down, or the vehicle delivers an anomalous signal, a rigorous protocol must be employed in order to re-establish or fix the telecommunications link. There are several factors that can contribute to link problems, such as malfunctions or mishandling of the ground station equipment, onboard failures of the spacecraft’s flight software coding, or even mishaps caused by the space environment itself. This chapter details the anomaly recovery protocols developed for the Cassini Mission-to-Saturn project, to resolve anomalous link problems as well re-acquisition of the spacecraft should a complete Loss of Signal (LOS) condition occur.