NeQuick-G and Android devices: a compromise between computational burden and accuracy

Ionospheric delay is one of the largest errors affecting Global Navigation Satellite System (GNSS) positioning in open-sky conditions and different methods are currently available for mitigating ionospheric effects including dual-frequency measurements and corrections from augmentation systems. For single-frequency stand-alone receivers, the most widely used approach to correct ionospheric delays is to rely on a model. In this respect, Klobuchar and NeQuick-G Ionospheric Correction Algorithms (ICAs) are the approaches adopted by GPS and Galileo, respectively. While the latter outperforms the Klobuchar model, it requires a significantly higher computational load, which can limits its exploitation in some market segments such as smartphones. In order to foster the adoption of the NeQuick-G model in this type of devices, a smart application of NeQuick-G is proposed. The solution relies on the assumption that ionospheric delays are practically constant over short time intervals. Thus, the update rate of the ionospheric correction computation can be significantly reduced. This solution was implemented, tested and evaluated using real data collected with a static smartphone in an ad hoc set-up. The impact of reducing the ionospheric correction update rate has been evaluated in terms of processing time, of ionospheric correction deviations and in the Ranging Error (RE) and position domains. The analysis shows that a significant reduction of the processing time can be obtained with negligible degradations of the navigation solution.

GIOIA Ciro;  BORIO Daniele; 

2022-02-16

MDPI

JRC121857

1424-8220 (online),   

https://www.mdpi.com/1424-8220/20/20/5908,    https://publications.jrc.ec.europa.eu/repository/handle/JRC121857,   

10.3390/s20205908 (online),