Multipath is the phenomenon whereby the signal from a satellite arrives at the receiver via multiple paths due to reflection and diffraction. These nondirect-path signals distort the received signal and cause errors in code and phase measurements. Differential techniques do not eliminate multipath and thus multipath is an important error source in high precision applications. The physical surroundings around the receiver’s antenna dictate the multipath environment and thus cause significant differences for land, marine, airborne, and spaceborne users.

This chapter describes the multipath environment and presents models describing the impact of multipath on code and phase measurements. The influence of the type and rate of the broadcast code as well as the receiver architecture will be highlighted. Mitigation techniques based on receiver design will also be described along with the impact of receiver dynamics. Finally, a technique to measure multipath is described and its usage in evaluating static environments is discussed.

The goal of this chapter is to provide the reader with the tools to assess the impact of multipath on both the code and phase and to understand the performance improvements and limitations associated with various multipath mitigation techniques.


Global Position System Global Navigation Satellite System Global Navigation Satellite System Elevation Angle Ionospheric Delay 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

binary offset carrier


binary phase-shift keying


composite binary offset carrier




continuously operating reference station


central processing unit


differential GNSS


delay lock loop


ground-based augmentation system


global navigation satellite system


Global Positioning System




pseudo-random noise


radio frequency


signal-to-noise ratio



The author would like to thank his current and former colleagues at Ohio University: Dr. Michael DiBenedetto, Dr. Sai Kalyanaraman (now with Rockwell Collins), and Mr. Joseph Kelly (now with mCube), along with Dr. Gary McGraw of Rockwell Collins, for their collaboration on various research projects that were drawn upon for material for this chapter. The author would also like to thank Dr. Dmitry Tatarnikov of Topcon Positioning Systems for the provision of the carrier-phase multipath data. Finally, the author would like to thank the US FAA, NASA, and DoD, along with Honeywell and Rockwell Collins for their support.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.School of Electrical Engineering & Computer ScienceOhio UniversityAthensUSA

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