Projects

Automotive Precise Positioning Systems

Challenges in Characterization of GNSS Precise Positioning Systems For Automotive

Autonomous cars of the future will need the assistance of very precise positionning systems that are far beyond what can be accomplished with Global Navigation Satellite System (GNSS).

Highly Automated Driving (HAD) is currently one of the main focus of attention in the automotive industry. A requirement for efficient and safe driving of autonomous vehicles is the ability to precisely pinpoint the location of the vehicle, in the decimeter to centimeter order of magnitude on a global scale. This problem is tackled by merging information from multiple sensors, in order to benefit from the best of each technology.

Improved GNSS (Global Navigation Satellite System) receivers, with support for multiple constellations, multiple signal bands and correction services, are expected to play a major role in HAD, providing high accuracy absolute positioning, a precise time reference and velocity information.

The performance announced by manufacturers of GNSS receivers are typically obtained in laboratory conditions or best-case scenarios, in which the receiver is static and in clear sky conditions, with direct line-of-sight to the satellites. However, due to the strict safety requirements for HAD, a full characterization in real-world driving conditions is mandatory to guarantee that the system is capable of providing high performance 24/7.

The focus of this project is to define requirements, methods and solutions for the characterization/evaluation of precise positioning systems for automotive in real world driving conditions. In this context, is necessary to define an architecture for a system that is globally available, to allow tests in different countries, and able to provide reliable and high precision absolute ground truth, with an accuracy of approximately. 2 cm, with 95% confidence level. This high quality ground truth will be used to perform a reliable evaluation of positioning systems for HAD.

Achieving the required performance is very challenging. This is especially true in demanding scenarios such as urban canyons or tunnels. A suitable architecture requires the combination of multiple technologies and high-grade sensors, such as Inertial Measurement Units (IMUs) and Distance Measurements Instruments (DMIs), as well as GNSS Correction Services, data fusion, and post processing techniques.