abstract:Reference datum height (RDH) is the height of a point that is located above the intersection of the runway centre line and the threshold and through which the downward extended straight portion of the glide path passes.Instrument Landing System Reference Datum Height Eurocontrol.
Somekey techniques, such as attitudecorrection, qualitycontrol of GPSheight, transformationofverticalreference datum and extraction of tidal level, are studied in detail.