Modeling techniques

The computerized frequency assignment program developed by the FCC Spectrum Management Task Force utilizes monitoring van1/ measured occupancy data and models for propagation, interference, and noise. The propagation model was constructed by the Technical Division of the FCC Office of the Chief Engineer from measured FM and television data2/ and National Bureau of Standards measurements in the UHF/VHF range.3/ The co-channel interference model uses commonly accepted signal ratios between desired and interfering signals. The adjacent channel interference model is based on performance characteristics furnished by the major Land Mobile (LM) equipment manufacturers. The receiver and transmitter intermodulation interference models and the noise model were taken from the Report of the Advisory Committee for the Land Mobile Services.4/ None of the models is considered immutable. All will be continuously updated.