Evaluation of GNSS receivers' performance in challenging environments.

Abstract

Advances in global navigation satellite system technology have resulted in smaller and more accurate GNSS receivers, which have become increasingly excellent for positioning through determination of the 3D position of a point on the earth's surface by measuring the distance from the receivers antenna to the orbital position of at least four satellites. But ground interferences to satellite signals on ground are increasing day by day and cannot be ruled out hence the need to adopt an eyes open approach ,recognizing and mitigating risks and using the best of the wide range of available receivers with their complementary benefits and availability to compensate for others' shortcomings , therefore this study investigated the accuracy and precision of four commercially available GNSS receivers in Uganda which were ProMark 800 ,ComNav's T300,CHC i90 and Trimble R8s. Through a closed link transverse ,test station C under canopy and station F near high rise structures were established for this evaluation. The accuracy of static GNSS positioning,for each point ,was evaluated by analyzing the processed positions from each GNSS receiver and the true landmark positions surveyed with the total station Leica T02. Overall the ProMark 800 and ComNav T300 performed better than the CHC i90 and Trimble R8s under canopy,while the ProMark 800 and CHC i90 performed better near high rise structures,making the ProMark 800 the overall best performing receiver with precision of +/- 0.002 m and accuracy of 0.008-0.096 m.