Automatic scaling of digital ionograms

A new system has been devised to automatically scale digital ordinary-ray ionograms. The system has been developed for use at mid-latitudes and has been trained on a full set of ionograms that are typical of the region. This paper describes the stages adopted in forming, recognizing, and scaling traces from the various ionospheric layers. Examples of the output available with this system and an error analysis of autoscaled parameters are presented as evidence of the system's capabilities.