Ronald Bruno

GSFC conceptual design study for an intersatellite optical multiple access communication system

System and terminal level specifications for an inter-satellite Optical Multiple Access (OMA) communication system are presented, as well as the resulting hardware designs for both OMA relay and OMA user terminals. The OMA relay terminal design uses a mechanical innovation which moves multiple fiber optic pickups in the focal plane, thereby providing simultaneous links with multiple OMA user terminals via a single telescope. Thus, with such a terminal on a relay satellite, multiple access service can be provided with a minimum of impact on the relay satellite.

Laser communication transceiver for space station Freedom

This paper describes the design of the Laser Communication Transceiver (LCT) system which was planned to be flight tested as an attached payload on Space Station Freedom. The objective in building and flight-testing the LCT is to perform a broad class of tests addressing the critical aspects of space-based optical communications systems, providing a base of experience for applying laser communications technology toward future communications needs. The LCTs functional and performance requirements and capabilities with respect to acquisition, spatial tracking and pointing, communications, and attitude determination are discussed.

A service availability simulation for the ATDRSS space segment

A Monte Carlo service availability simulation (SAS) model has been developed as a tool to support the architecture evaluation process for NASAs Advanced Tracking and Data Relay Satellite System (ATDRSS). The key component of the simulation is the spacecraft (S/C) reliability model which utilizes data on S/C subsystems for component configuration, reliability, and redundancy for the faithful generation of random S/C failures. The SAS logic responds to these failures to simulate the appropriate NASA responses for the launch and deployment of new S/C. The outputs of the simulation include the probability that the system meets projected communications requirements over time, required space-ground link capacity, statistics of future S/C launch dates, and number of S/C required over the system life cycle. The SAS is capable of modeling a broad set of system architectures and S/C configurations. Sample applications are described.<<ETX>>

A Shuttle Based Laser System For Space Communication

The Goddard Space Flight Center (GSFC) is planning a series of space communication experiments to validate laser technology for future NASA missions. Requirements include sevelal hundred MBPS data relay in the near earth environment and approximately one MBPS over the deep space to earth link. A key element in this program is a Shuttle-based laser system called the Laser Technology Experiments Facility (LTEF). This Facility will be designed to communicate with a cooperative laser system under development for the Advanced Communication Technology Satellite (ACTS) and will conduct a comprehensive set of acquisition, tracking and communication experiments. This report presents the results of the initial study of this Facility with particular emphasis on the challenges associated with LTEF acquisition of the ACTS downlink beacon laser.