An Automated Technique for Calculating Interference from Airborne Transmitters to Terrestrial Receivers

摘要

A computer program (ATTIC) has been developed with the ability to automatically compute and plot interference contours around existing microwave systems when new airborne systems are proposed or planned. The frequency manager or spectrum analyst can utilize ATTIC to vary the airborne system parameters and examine the size of the interference contours. The ATTIC program implements a procedure for determining the level of interference generated in a terrestrial microwave terminal (or system of microwave terminals) by an airborne telecommunication system. The output of this procedure is a set of contours defining those aircraft positions which produce a constant signal-to-interference (S/I) ratio to the terrestrial systems being analyzed. The S/I contours are plotted on a map with U.S. state boundaries. The user supplies the basic aircraft data while the terrestrial receiver(s) data are obtained from a computer accessible data base. Although program flow and program limitations will be discussed in this report, emphasis is on implementing ATTIC, interpreting the output, and presenting sample analyses.