SpringerLink - Journal Article

Original Article

Advantage of velocity measurements on instantaneous RTK positioning

Nobuaki Kubo¹

(1)	Tokyo University of Marine Science and Technology, 2-1-6 Etchujima, Koto-ku, Tokyo 135-8533, Japan

Received: 28 October 2008 Accepted: 20 February 2009 Published online: 10 March 2009

Abstract Instantaneous real-time kinematic (RTK) techniques are one approach to achieving real-time high-accuracy positioning. The object of this paper is to show the advantage of adding velocity information to instantaneous RTK positioning. In this paper, velocity from Doppler frequency measurements is used to help resolve integer ambiguities in the LAMBDA method. In urban areas, pseudorange measurements can suffer from significant errors due to strong multipath, despite the use of advanced multipath-mitigation techniques. However, Doppler frequency measurements do not deteriorate as much as pseudoranges, because the multipath error on Doppler frequency measurements is only in the range of several centimeters. Our proposed method has been tested by both static and moving users in sub-urban environments. Single-epoch ambiguity fixing performance was improved compared to conventional ambiguity resolution without velocity information.

Keywords RTK - Ambiguity resolution - Doppler frequency - Velocity - Multipath

Nobuaki Kubo
Email: nkubo@kaiyodai.ac.jp
Email: nobu_rtk@yahoo.co.jp

Dr. Nobuaki Kubo received his Master of Engineering (Electrical) degree in 1998 from Hokkaido University. He received his doctorate in engineering from the University of Tokyo in 2005. He is now an associate professor at the Tokyo University of Marine Science and Technology (TUMSAT) in the area of GPS/GNSS systems. He currently resides at Stanford University, where he is a visiting scholar in 2008. His current interests are high-accuracy automobile navigation using RTK and multipath-mitigation techniques.

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