Predicting C/N₀ as a Key Parameter for Network RTK Integrity Prediction in Urban Environments

authored by

Ali Karimidoona, Steffen Schön

Abstract

Autonomuous transportation systems require navigation performance with a high level of integrity. As Global Navigation Satellite System (GNSS) real-time kinematic (RTK) solutions are needed to ensure lane level accuracy of the whole system, these solutions should be trustworthy, which is often not the case in urban environments. Thus, the prediction of integrity for specific routes or trajectories is of interest. The carrier-to-noise density ratio (C/N (Formula presented.)) reported by the GNSS receiver offers important insights into the signal quality, the carrier phase availability and subsequently the RTK solution integrity. The ultimate goal of this research is to investigate the predictability of the GNSS signal strength. Using a ray-tracing algorithm together with known satellite positions and 3D building models, not only the satellite visibility but also the GNSS signal propagation conditions at waypoints along an intended route are computed. Including antenna gain, free-space propagation as well as reflection and diffraction at surfaces and vegetation, the predicted C/N (Formula presented.) is compared to that recorded by an Septentrio Altus receiver during an experiment in an urban environment in Hannover. Although the actual gain pattern of the receiving antenna was unknown, good agreements were found with small offsets between measured and predicted C/N (Formula presented.).

Organisation(s)

Institute of Geodesy

Type

Article

Journal

Remote sensing

Volume

15

ISSN

2072-4292

Publication date

07.10.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Earth and Planetary Sciences(all)

Sustainable Development Goals

SDG 11 - Sustainable Cities and Communities

Electronic version(s)

https://doi.org/10.3390/rs15194850 (Access: Open)