Manufacturers of dual frequency GPS systems could soon face a challenge from highly accurate smartphones.
Smartphone global positioning systems have been significantly improved thanks to trans-Tasman research by the University of Otago and Curtin University.
The research, recently published in the international Journal of Geodesy, explains how by combining signals from four different Global Navigation Satellite Systems (GNSSs) it is possible to achieve centimetre (CM)-level precise positioning on a smartphone.
The University of Otago’s Dr Robert Odolinski and Curtin University colleague Prof Peter Teunissen led the research.
“It’s all down to the mathematics we applied to make the most of the relatively low-cost technology smartphones use to receive GNSS signals, combining data from American, Chinese, Japanese, and European GNSS," Odolinski said.
"We believe this new capability will revolutionise applications that require cm-level positioning."
For decades, construction, engineering, cadastral surveying and earthquake monitoring have relied on high-cost, "dual-frequency", GPS positioning to obtain centimetre-level location information.
The challenge is that GPS signals, travelling from Earth-orbiting satellites to receivers on the ground, are disrupted along the way, and this generates errors and limiting precision.
Furthermore, the traditional solution is to combine GPS signals sent at two different frequencies to improve the positions, but the antennas and receivers required have been expensive, says Odolinski.
The new approach uses only one of two frequencies but collects data from more satellites, for what is called a “multi-constellation” GNSS solution.
The extra data combined with "clever maths" is used to improve positioning without adding cost.
The researchers have shown this approach can produce competitive results compared to dual-frequency GPS solutions.
Odolinski said he believes that countries and industries of all sizes can benefit from using smartphones as GNSS receivers, and is confident commercial application and development will flow from the research.
“This significant reduction in costs when using smartphones can increase the number of receivers that can be deployed, which will revolutionise a range of disciplines requiring centimetre-level positioning, including precise car navigation, surveying, and geophysics (deformation monitoring), to name a few.”