Differential GPS makes the difference

The accuracy of GPS is greatly improved in "diferential GPS", which utilizes an additional stationary GPS receiver to make positional corrections to the basic GPS data.

Results of independent benchmark testing of a stationary GPS_1000 collar in both non-differential and differential GPS modes:

Source: Ron Moen, John Pastor & Yosef Cohen, Natural Resources Research Institute and Department of Fisheries and Wildlife, University of Minnesota

Telemetry System Location Accuracy

Differential GPS as compared to a non-differential GPS, Argos and conventional aircraft tracking.

typical degree of accuracy achieved subject to Selective Availability and multipath error. For information on GPS accuracy reference: Performance of a GPS Animal Location System under Boreal Forest Canopy. Journal of Wildlife Management 59 (3): 543-551

highest observed accuracy based on 68 percentile error for location quantities recorded for >4 satellite messages received under near-optimum conditions. Source: Satellite Telemetry: Performance of Animal-Tracking Systems, Journal of Wildlife Management 55 (1): 160-171

highly variable, subject to such factors as altitude, speed, location procedures, prevalence of landmarks, researcher fatigue, etc. "Errors in excess of 0.5 km have been reported for aerial location estimates made when the animal was not visibly located." -- Source: White and Garrott, Analysis of Wildlife Radio Tracking, 43

For a more in-depth information on the accuracy of differential GPS, view the on-line tutorial on differential GPS published by the Trimble corporation.

Back to main GPS page