Accession Number : AD0918427

Title :   Acquisition and Tracking Assembly II.

Descriptive Note : Final rept. 2 Aug 72-30 Jun 73,

Corporate Author : MCDONNELL DOUGLAS ASTRONAUTICS CO ST LOUIS MO

Personal Author(s) : Lowry, James H., Jr. ; Wolf, J. D. ; Carter, J. P.

Report Date : 15 FEB 1974

Pagination or Media Count : 290

Abstract : A brassboard demonstration system was fabricated, tested, and exercised to compile parametric data on the acquisition and tracking portions of a 1 Gbps laser communication subsystem. The demonstration system consists of three primary parts: the acquisition and tracking package, precision instrumentation equipment, and simulation equipment. The brassboard acquisition and tracking package utilizes three electrooptic detectors to sense the incoming signal from a cooperative beacon laser, a two axis gimbaled mirror for coarse pointing, and high frequency piezoelectric bender bimorph mirrors for fine pointing. The precision instrumentation equipment measures the pointing error of the brassboard acquisition and tracking package with an accuracy of 0.1 microradian. The simulation equipment provides beacon laser signals, background noise, realistic satellite limit cycles, satellite flexure effects, and orbital kinematic motions of the line-of-sight vector during acquisition and tracking. The brassboard system demonstrates the total automatic sequence of operations to verify the performance of all three stations: low altitude satellite, synchronous satellite, and ground. Engineering data is presented on the basic modes of operation, the optical detectors, the control system, and the satellite dynamical effects. Performance data showed a system acquisition sensitivity at 1.06 micrometer of 9 photoelectrons per pulse.

Descriptors :   *SATELLITE COMMUNICATIONS, *LASER COMMUNICATIONS, *SATELLITE TRACKING SYSTEMS, *NEODYMIUM LASERS, *INFRARED DETECTORS, INFRARED TRACKING, PULSE COMMUNICATIONS, INFRARED PULSES, INFRARED LASERS, TARGET ACQUISITION, INFRARED BEACONS, MIRRORS, GIMBALS, AIMING, BACKGROUND, SYNCHRONOUS SATELLITES, PHOTOMULTIPLIER TUBES, NEAR INFRARED RADIATION, Q SWITCHING, EFFICIENCY, QUANTUM EFFICIENCY, ERRORS, ACCURACY, SILICON, ATTITUDE CONTROL SYSTEMS, BRASSBOARD MODELS.

Subject Categories : Lasers and Masers
      Infrared Detection and Detectors
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE