Tag: Curtin University

  • University research uses smartphones for precision GNSS

    New research conducted at the University of Otago, New Zealand, and published in the August issue of Journal of Geodesy demonstrate that it is possible to achieve centimeter(cm)-level precise positioning on a smartphone.

    The research, conducted in collaboration with Curtin University, Australia, combined signals from four different GNSS, according to Otago’s Dr. Robert Odolinski and Curtin University colleague Prof. Peter Teunissen.

    “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. We believe this new capability will revolutionize applications that require cm-level positioning,” Odolinski says.

    He said to understand the new technology, a look back at the historical scientific context is needed.

    Precise centimeter-level positioning on a smartphone during 24 hours in Dunedin, New Zealand. Blue dots show repeatability of one epoch data in comparison to precise benchmark coordinates. The repeatability is more or less the size of a one-dollar New Zealand coin (diameter of 2.3 cm) in all three dimensions. (Image: University of Otago)
    Precise centimeter-level positioning on a smartphone during 24 hours in Dunedin, New Zealand. Blue dots show repeatability of one epoch data in comparison to precise benchmark coordinates. The repeatability is more or less the size of a one-dollar New Zealand coin (diameter of 2.3 cm) in all three dimensions. (Image: University of Otago)

    “For decades, construction, engineering, cadastral surveying and earthquake monitoring have relied on high-cost, dual-frequency GPS positioning to obtain centimeter-level location information. The challenge is that GPS signals, traveling from Earth-orbiting satellites to receivers on the ground, are disrupted along the way, and this generates errors and limiting precision.

    “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, far beyond the reach of many who would benefit from the technology,” Odolinski said.

    The new approach uses only one of two frequencies but collects data from more satellites for a multi-constellation GNSS solution. The extra data and algorithms are used to improve the positions without adding cost.

    Odolinski and Teunissen have shown that this approach can work in smartphones, producing competitive results compared to dual-frequency GPS solutions (see figure).

    Odolinski believes that countries and industries of all sizes can benefit from using smartphones as GNSS receivers, and is confident commercial application and development will spring from this research.

    “This significant reduction in costs when using smartphones can increase the number of receivers that can be deployed, which will revolutionize a range of disciplines requiring centimeter-level positioning, including precise car navigation, surveying and geophysics (deformation monitoring), to name a few.”

    Read the full research paper.

    Robert Odolinski configuries a smartphone to collect multi-GNSS data. (Photo: University of Otago)
    Robert Odolinski configuries a smartphone to collect multi-GNSS data. (Photo: University of Otago)
  • QZSS satellites benefit Western Australia industries, study shows

    Curtin University researchers found the launch of new Japanese satellites has boosted satellite positioning capabilities in Western Australia (WA), offering huge potential benefits across numerous industries including mining, surveying and navigation.

    New research, published in the journal GPS Solutions, found signals from the recently launched Japanese QZSS satellites provide centimeter-level positioning accuracy, and thus significantly enhanced positioning capabilities in WA, thereby improving accuracy, reliability and availability.

    Lead researcher Professor Peter Teunissen, of Curtin’s School of Earth and Planetary Sciences, said these results will improve further when the QZSS signals are combined with those from other satellite systems such as the Indian NavIC system.

    Teunissen said the analyses done by Curtin’s GNSS Research Centre demonstrated the highly accurate centimeter-level positioning capabilities that can now be achieved.

    “Such improved positioning, accuracy and reliability would offer great benefits when applied in fields such as open-pit mining, surveying, hydrography, automated navigation, structural health monitoring, and subsidence and tectonic deformation monitoring used in the geospatial industry,” Teunissen said. “The benefits are not only restricted to positioning, but cover the whole range of satellite signal applications, including atmospheric sensing (ionosphere and troposphere) as used for climate change and space weather studies, and numerical weather prediction.”

    Teunissen said WA was in the fortunate and unique geographical position of being located beneath the flight paths of both the Japanese QZSS and the Indian NavIC regional satellite systems.

    “Using both satellite systems, QZSS and NavIC, offers huge benefits to users in Australia – and this is an opportunity to work on future developments with such technologies,” Professor Teunissen said.

    “The United States of America, for example, can’t use these signals the way we can in Australia, so this places us in a position of great advantage when it comes to the understanding, modelling and analyses of these satellite signals and their many practical applications.

    “The tracking and analyses were done using Javad GNSS receivers and Curtin’s theory of integer ambiguity resolution, which enables millimeter-level satellite ranging, and was achieved with the use of only the four currently available QZSS satellites.”

    The results bode well for the future, with the Japanese system being further developed from the current four-satellite system into a mature seven-satellite system that is expected to be operational by 2020.

    The report, “Australia-First High-Precision Positioning Results with New Japanese QZSS Regional Satellite System, is available online.