Towards a Plug&Play Solution for Real-Time Precise Positioning on Mass-Market Devices

Abstract

Despite pedestrian and vehicle navigation are the key applications enabled by the development of GNSS technology, the best approach to obtain accurate, reliable, continuous and robust PVT (Position-Velocity-Timing) solutions for this purpose has yet to be identified. The real limiting factor is the environment in which the users usually navigate: e.g. multipath effects and cycle slips in harsh urban environments strongly affect, respectively, pseudorange measurements and the continuity of carrier-phase observations. Therefore, positioning services relying on code-based algorithms cannot always meet the required accuracy – which varies depending on the targeted use case –; on the other hand, phase-based approaches as Real-Time Kinematic (RTK) and Precise Point Positioning (PPP) require strong effort to deal with the ambiguity term and its reinitialization when cycle slips occur. These problems are amplified when GNSS measurements from Android smartphone are considered due to the low-cost, linearly polarized and multi-purpose antenna which inevitably impacts on the quality of GNSS observables. This paper focuses on the performance analysis of GNSS POWER - an algorithm based on the loosely coupling between Single Point Positioning (SPP) solutions and variometric velocity - combined with IGS SSR corrections to increase the accuracy achievable in a real-time stand-alone solution. The integration of SSR corrections within GNSS POWER algorithm is validated in both static and kinematic scenarios using high-end GNSS receivers and Andorid smartphones. The results demonstrated the advantages of using SSR corrections on SPP and GNSS POWER solutions also on Android devices opening to new applications of real-time stand-alone positioning approaches on mass-market devices.