Which is more accurate - SpotOn GPS Fence or the other leading GPS smart fence?

Spirent has over 50 years of industry experience. Known for their expertise, control, and precision when evaluating positioning, navigation, and timing technology (PNT) and global satellite navigation systems (GNSS), they have developed automated solutions for testing to CTIA OTA standards and are eligible to perform PNT tests to IEEE standards. Spirent has set standards in CTIA OTA tests and is able to perform PNT tests to IEEE standards. The lab was commissioned to test the European GNSS constellation Galileo, mission-critical GPS technology for NASA, at Deutsches Zentrum für Luft- und Raumfahrt (DLR) (Germany's Research Center for Aeronautics and Space), and for tech giants like Meta.

Spirent performed advanced GNSS testing on SpotOn and the only other leading GPS smart fence to scientifically compare the precision of the two systems. The purpose was to determine which product offered greater positioning accuracy and overall performance.

Robust real-time positioning accuracy is the most critical element of a GPS fence. Accuracy is vital to fulfill the product’s promise—to keep dogs safely contained within a designated area—but also because of how the fence boundary works. A series of escalating warnings, followed by a static correction, keep the dogs within a “fence.” Inaccurate GNSS measurements could lead to the correction being applied in the wrong location or not at all, resulting in the dog escaping the fence and getting lost or killed.

Since all GPS products are impacted by GPS drift, a phenomenon where the reported GPS position of a device, varies over time, even when stationary, it was expected that there would be some movement in the fence lines. 

Spirent designed a series of tests that evaluated six aspects of GNSS performance in six lab simulations that tested only the hardware of both products (SpotOn's U-blox antenna/receiver combo vs the competition's Airoha Technology receiver and competitor's antenna) and five outdoor environments representing real-life scenarios.

Lab environments

Hardware-only tests evaluate the base-level performance of the components that power each of the GPS fences. The outdoor field testing tested the hardware in conjunction with each product’s operating system and app integration.

Lab tests used a Spirent GSS7000 multi-frequency, multi-constellation GNSS signal simulator to generate GNSS signals and the RF interference waveforms (for the interference test). Spirent also used Sim3D software to model multipath patterns and signal obscuration accurately in the area of downtown San Jose, California (where the live sky testing would take place) to ensure maximum realism in the lab. The positional accuracy and time to acquire a GPS fix in the lab favored the U-blox antenna/receiver hardware combination in the SpotOn GPS Fence. SpotOn’s U-blox receiver demonstrated a greater ability to acquire and maintain a connection with satellites and had greater tracking sensitivity. 

Outdoor environments

Both collars were tested in outdoor locations at Spirent’s San Jose test facility, a local natural park setting, and downtown San Jose (for the tracking accuracy test). The first five scenarios were repeated ten times to ensure a fair and rigorous comparison. SpotOn performed consistently within its stated specification the GPS fence boundary shifting no more than 10 feet.  

In the field testing, the accuracy of SpotOn Fence and the competing product were both tested to their stated specifications. Each system used a series of two alerts before the fence line and issued a correction at the fence line. SpotOn's alerts are issued 10 feet before the fence line, again at 5 feet before the fence line, and the correction issued at the fence line. The competing product's first alert is issued at 7-10 feet before the fence line, and the correction issued at the fence line (there was no specification available for the second alert).

For each product, two identical virtual fences were created by using each device's mobile app. To measure the accuracy of the fence line, the team measured distance away from the fence, and the time it took for each device to broadcast alerts and correction, measuring tapes and flags were used, respectively.

For the cityscape live tracking evaluation, a reference GNSS receiver with a multi-band GNSS antenna was used to provide the truth position, velocity, and time (PVT) information to compare against each device’s GNSS solution.