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A model for HF spectral occupancy in Central Australia

Models for HF spectral occupancy or congestion as a function of time, geographic location and solar activity have been developed by several researchers, based on limited data sets recorded at several northern hemisphere locations. In this report, the extensive database of HF spectral surveillance and background noise measurements, recorded at Alice Springs in Central Australia as part of the Jindalee over-the-horizon radar project, is used to develop a model for HF channel availability. The resulting model may be used for short-term forecasting of HF channel availability for radar and communications, and as the starting point for a study into long-term trends in spectral usage.