TDRSS telecommunications system, PN code analysis

The pseudo noise (PN) codes required to support the TDRSS telecommunications services are analyzed and the impact of alternate coding techniques on the user transponder equipment, the TDRSS equipment, and all factors that contribute to the acquisition and performance of these telecommunication services is assessed. Possible alternatives to the currently proposed hybrid FH/direct sequence acquisition procedures are considered and compared relative to acquisition time, implementation complexity, operational reliability, and cost. The hybrid FH/direct sequence technique is analyzed and rejected in favor of a recommended approach which minimizes acquisition time and user transponder complexity while maximizing probability of acquisition and overall link reliability

A comparison of DDS and DRFM techniques in the generation of "smart noise" jamming waveforms

This thesis presents a comparison of the effectiveness of 'smart noise' jamming waveforms against advanced threat radars, which are generated using either Direct Digital Synthesis (DDS) or Digital RF Memory (DRFM) based support jamming. The challenge lies in the fact the modern radar employs advanced waveforms, ultralow sidelobe antennas, coherent sidelobe cancelers, and sidelobe blankers to inhibit signals entering through its sidelobes. This thesis compares the effectiveness of using DDS versus DRFM techniques to meet this challenge. In particular, the effect of mismatched frequency on the DDS jamming waveform is described, as is the effect of quantization and multi-signal storage in the DRFM. A quantitative comparison of these jamming techniques against the AN/TPS-70 surveillance radar is madehttp://archive.org/details/comparisonofddsd00watsCaptain, United States ArmyApproved for public release; distribution is unlimited

TDRSS telecommunications study. Phase 1: Final report

A parametric analysis of the telecommunications support capability of the Tracking and Data Relay Satellite System (TDRSS) was performed. Emphasis was placed on maximizing support capability provided to the user while minimizing impact on the user spacecraft. This study evaluates the present TDRSS configuration as presented in the TDRSS Definition Phase Study Report, December 1973 to determine potential changes for improving the overall performance. In addition, it provides specifications of the user transponder equipment to be used in the TDRSS

Shuttle communications design study

The design and development of a space shuttle communication system are discussed. The subjects considered include the following: (1) Ku-band satellite relay to shuttle, (2) phased arrays, (3) PN acquisition, (4) quadriplexing of direct link ranging and telemetry, (5) communications blackout on launch and reentry, (6) acquisition after blackout on reentry, (7) wideband communications interface with the Ku-Band rendezvous radar, (8) aeroflight capabilities of the space shuttle, (9) a triple multiplexing scheme equivalent to interplex, and (10) a study of staggered quadriphase for use on the space shuttle