Omega signal coverage prediction in the 1990s

The evolution of Omega signal coverage portrayal is briefly traced from the early compilation of hard copy world maps to the current electronic format, with emphasis on the display medium rather than the scientific bases of signal coverage. The outlook for Omega signal coverage displays in the 1990s is examined on the basis of projections of current technology and user requirements. Future coverage displays are expected to do more than indicate the available station signals at a selected geographic location: Omega coverage displays of the 1990s are likely to include increased time resolution, attainable position accuracy, probability of station signal outage (due to station off-air, local noise spikes, or propagation effects), and coverage during anomalous ionospheric events