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M. Glaner, K. Gutlederer, R. Weber:
"PPP with raw GNSS observation data of smartphones";
Talk: Scientific Assembly of the International Association of Geodesy (IAG 2021), Beijing, China; 2021-06-28 - 2021-07-02; in: "IAG 2021 - Abstract Book", (2021), 424.

Precise Point Positioning (PPP) is one of the most promising processing techniques for Global Navigation Satellite System (GNSS) data and well-established for geodetic receivers. Unlike relative positioning methods, PPP does not rely on nearby reference stations or a regional reference network. PPP is characterized by the use of precise satellite products (orbits, clocks, and biases) and the application of sophisticated algorithms to estimate the user´s position. Typically, code and phase observations on multiple frequencies are required to build the ionosphere-free linear combination.Since the release of Android 7.0 in 2016, the raw GNSS measurements of smartphones operating with Android can be accessed. Therefore, the smartphone´s GNSS observations are processed directly to estimate the user position with specialized self-developed algorithms and correction data. However, smartphones provide challenging, low-quality GNSS measurements because they are equipped with simple, cost-effective GNSS chips and antennas. Furthermore, they mainly offer GNSS measurements on only one frequency, which prevents to build the ionosphere-free linear combination. In this contribution, we discuss the necessary adaptions of PPP to handle the demanding raw GNSS observations from smartphones in the best way. Therefore, we present various strategies and the application of the uncombined PPP model with ionospheric constraint. This flexible PPP model avoids building the ionosphere-free linear combination, is suitable for any number of frequencies, and allows the utilization of ionosphere models as an ionospheric constraint. In this way, a position accuracy at the decimeter level is achieved. The PPP calculations are performed with our self-developed in-house software raPPPid.

GNSS, PPP, smartphone

https://files.sciconf.cn/upload/file/20210626/20210626085039_69146.pdf