Characterization and extraction of global positioning system multipath signals using an improved particle-filtering algorithm

Driving down multipath errors is probably the single most important objective of the current research into the use of the global positioning system (GPS) for high-accuracy applications. This paper focuses on the characterization of multipath signals and techniques for their removal by improved particle filtering. By the characteristic analysis of the GPS multipath signal in carrier phase observations, a specific set of generating and monitoring systems for multipath signals is established and a series of controlled experiments are carried out to assess the efficiency of the improved particle filtering. Experimental results show that the method has the advantage of being able to adapt to the close reflector situation, while remaining quite efficient when the reflector gets further away. The extracted multipath signals may be used to improve positioning accuracies.