SATELLITE VIBRATION MEASUREMENTS WITH AN AUTODYNE CO2-LASER RADAR

Vibration signatures of the Low Power Atmospheric Compensation Experim ent satellite were obtained with a ground-based CO2 laser radar. The l aser radar operated in a cw mode and used autodyne receivers to extrac t relative target velocity information between a germanium retroreflec tor located at the base of the satellite and a retroreflector array lo cated at the tip of an extended forward boom. Time-frequency analysis algorithms were applied to the vibration data to investigate the corre lation between excitations and modal structure. The resultant analysis suggests that vibration modes of an on-orbit spacecraft can be suppre ssed with simple open-loop techniques.