Telemetry, Tracking and Command System Simulator. Volume 1: Simulation Model

摘要

Theoretical problems involved in the simulation of a satellite tracking telemetry and control system are discussed. To simulate the system the signal at any point is represented by a set of samples, of real baseband waveform or complex envelope in the time domain or of baseband or radiofrequency spectrum in the frequency domain. The fast Fourier transform is used to switch between domains. The simulation of phase locked loops is shown to require a closely sampled spectrum. The function of the interplex transmitter is described. Methods for extracting a timing reference with and without prior modulation by a clock waveform are shown. Phase correction techniques on the phase shift keying complex envelope to restore the nominal signal phases to + or - 90 deg are shown. Digital signals are put through either an integrate and dump circuit or a matched filter to enable optimal decoding. Viterbi decoder error analysis techniques are shown.