Wide area differential GPS (WADGPS): future navigation system

Conventional differential Global Positioning System (DGPS) usually has accuracies of 1-3 within 100 km of the reference station wide area differential GPS (WADGPS) can achieve the same accuracy as DGPS in much wider area while reducing the number of reference stations and increasing the integrity substantially. Test results have shown 1.5-4 m positioning accuracy for a dual frequency user with 10-20 s of age using WADGPS, which in this case has six monitor stations with a 1632 km minimum baseline.