Engineering topics
Publications and source records attributed to Wilson, K..
We have performed a study on telecommunication systems for a hypothetical mission to Mars. The objective of the study was to evaluate and compare the benefits that microwave (X-band and Ka-band) and optical communications technologies afford to future missions.
In this Par-II report of the Advanced Communications Benefits study, two critical metrics for comparing the benefits of utilizing X-band, Ka-band and Optical frequencies for supporting generic classes of Martian exploration missions have been evaluated.
Optical communications offers high data rate satellite to ground communications in a small, low mass, and low power consumption package.
Adaptive optics can mitigate the turbulence-induced wavefront distortions that limit the minimum practical beam divergence in a ground-to-space optical link, and enable high intensity laser beam propagation through the atmosphere. The CEMERLL experiment will use laser guide star adaptive optics to transmit a near-diffraction-limited laser beam from the Starfire Optical Range to the Apollo lunar retro-reflectors. The experiment will validate theoretical models that predict the effect of atmospheric turbulence on uncompensated and compensated laser beam propagation, and explore strategies to compensate for atmosphere-induced wavefront tilt not corrected for by laser guide star adaptive optics.
The requisite SNR for optical beacons or uplink command signals sent to deep space probes can be achieved by either developing high repetition rate high peak power lasers and associated high-damage-threshold optical components or by propagating near-diffraction-limited beams to the spacecraft.
This paper describes the data analysis based on the image frames received at the Solid State Imaging camera of the Galileo Optical-communications from an Earth-based Transmitter demonstration conducted between December 9 and December 16 of 1992.
The VISC code is a computer automated scheme for solving the equations describing the fully coupled viscous, radiating flow at the stagnation-point of a blunt body which may or may not be ablating. The code provides a basis for obtaining prediction of the stagnation-point heating to a body entering any planetary atmosphere at hyperbolic velocities. The code is written in FORTRAN V and is operational on both the Univac 1108 (EXEC 8) system and the CDC 7600 system. The report gives an overview of the VISC code computational logic flow, a description of the input requirements and output results and comments on the practical use of the code. As such the report forms a users manual for operation of the VISC code.