When the Land Survey Department of Sarawak wanted to upgrade its cadastral survey capability, it held a competition among six leading brands to determine the best GNSS receiver for its needs. The clear winner in all seven of the benchmark tests, conducted by the Land Survey Department, was the Spectra Precision SP80 GNSS receiver.
In the tropical rainforest climate of Sarawak, where 420 cm of rain falls on 250 days annually, dense vegetation and tree canopy presents extraordinary challenges for GNSS receivers. One key test assessment devised by the Land Survey Department was an electronic distance measurement (EDM) test under heavy – 90 percent covered – tree canopy. The test took measurements to two points each more than 13 km distant. The Spectra Precision SP80, with its 240-channel chipset optimized for tracking and processing signals from all GNSS constellations, won this contest repeatedly with all measurements within five millimeters of the known distance.
Another important test conducted by the Land Survey Department was RTK performance. The competing receivers, each using their internal two-watt radios, were judged on distance and time to fix. The SP80, with it’s unique GNSS-centric capability that optimally combines GNSS signals without dependency on any specific GNSS system, was clearly the best receiver completing a fix in one second on a 8.7 km base line, the longest baseline achieved by any competitor.
A third test compared the accuracy and repeatability of two five-minute static surveys. Conducted from atop the EDM test pillar to two known, x, y and z, points, each competitor was tested for two five-minute static observations. The SP80 proved the most accurate and precise.
Though a heavy rain test was not a part of the test protocol, the three-day test period was conducted in nearly continuous heavy rain. The Land Survey Department was impressed with the flawless performance of the SP80 despite the drenching conditions.
In each of the other three tests: network test, cadastral reference mark (CRM) test, and the post-processed kinematic (PPK) test; the Spectra Precision SP80 bested all competitors.
The SP80 receiver used in the tests was provided and represented by Surmap Sdn Bhd, the Spectra Precision distributor in Malaysia, which went on to win the bid and secure the multiple unit contract.