Low-cost Precise Vehicular Positioning in Urban Environments

Todd E. Humphreys, Matthew Murrian, Lakshay Narula

Abstract:	A system developed at The University of Texas for low-cost precise urban vehicular positioning is demonstrated to provide sub-decimeter-accurate solutions for 90% of measurement epochs in an hour-long urban test campaign without any aiding by inertial or vision sensors. Development and evaluation of the unaided GNSS-based precise positioning system is a key milestone toward the overall goal of combining precise GNSS, vision, radar, and inertial sensing for all-weather high-integrity precise positioning for automated and connected vehicles. The system described and evaluated herein is composed of a denselyspaced reference network, a software-defined GNSS receiver whose processing can be executed on general-purpose commodity hardware, and a real-time kinematic (RTK) positioning engine. All components have been tailored in their design to yield competent sub-decimeter positioning in the mobile urban environment. A performance sensitivity analysis reveals that navigation data bit prediction on the GPS L1 C/A signals is key to successful urban RTK. Other important factors are (i) elimination of ionospheric and tropospheric errors to below the rover’s phase noise variations, (ii) vectorized tracking and PLL bandwidth adaptation to prevent frequency unlock during deep fading, and (iii) tracking an average of at least 14 double-difference signals.
Published in:	2018 IEEE/ION Position, Location and Navigation Symposium (PLANS) April 23 - 26, 2018 Hyatt Regency Hotel Monterey, CA
Pages:	456 - 471
Cite this article:	Humphreys, Todd E., Murrian, Matthew, Narula, Lakshay, "Low-cost Precise Vehicular Positioning in Urban Environments," 2018 IEEE/ION Position, Location and Navigation Symposium (PLANS), Monterey, CA, April 2018, pp. 456-471.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In