Telcom-Time Variable Telecommunications Performance Prediction Program

Abstract

The TELCOM program has been developed to aid in the design and analysis of spacecraft telemetry and communication systems. Given a spacecraft trajectory, it is often desired to predict the total received power of the transmission link. Since the gains and losses of the individual link components are dependent on the spacecraft trajectory, as well as the spatial orientation of the spacecraft, the received signal power varies as a function of time along the flight path. TELCOM organizes the time variable information and calculates the received signal power in the subcarrier and/or carrier predetection bandwidths at specified time intervals. The spacecraft trajectory information and. antenna gain contours are stored on magnetic tape. The time in-variant quantities are provided by the user so that he may easily make parametric studies to determine the effect of link constants on system performance. TELCOM output options include printed values of received signal power at specified. time intervals, plots of signal power, range, look angle versus time, and DB margin summaries at specified points along the trajectory.