Positioning and digital maps

A reliable positioning system is essential for the development of intelligent vehicles. This chapter provides an overview of different technologies and techniques that are crucial to understand modern positioning systems onboard road vehicles. It is written for the purpose of serving as a guide to students, engineers, and researchers in the field of vehicular technology or Intelligent Transportation Systems. In Section 4.1, after an introduction to the problem, a handy list of key definitions is provided, and some of the most relevant Location-Based Services mentioned. Section 4.2 presents the fundamentals of GNSS-based positioning. Aiding technologies, such as odometers and inertial sensors, and techniques for GNSS-based hybridized positioning are discussed in Section 4.3. Later, Section 4.4 analyzes the role of digital maps, map-matching, and map-aided positioning. Finally, Section 4.5 introduces alternatives to GNSS, such as visual odometry, with a brief mention of wireless networks and RFID.