An F1 layer MUF prediction system for Northern latitudes

Ionospheric propagation via the F1 layer is important for transmission distances in the 2000-3400 km range. Existing prediction systems yield large discrepancies between the predicted and observed F1 layer maximum usable frequencies (MUFs). An improved F1 layer prediction system has been developed which can be used for predicting the F1 layer MUF for latitudes greater than
40\deg
North. Contour maps of zero distance F1 layer MUF and distances factors, for use with any sunspot number, are included for the prediction of the F1 layer MUF for April, June, August, and October.