Real-Time Geometry-Based Cycle Slip Resolution Technique for Single-Frequency PPP and RTK

Raw carrier phase measurements from the Phase Lock Loop can be used to improve position accuracy. Techniques such as Real-Time Kinematic, Precise Point Positioning or code smoothing use the constancy of the ambiguity value over time to obtain a precise position. In the case of a cycle slip, these techniques have to be reinitialized which degrades the final quality of the solution. Although many techniques exist for dual-frequency data, single-frequency cycle slip resolution is still an open problem [Takasu, et al., 2008]. In this paper, a single-frequency ambiguity resolution technique based on Doppler measurements is presented. Instead of treating each satellite separately, the entire geometry is used to determine the cycle slip float solution. Moreover, an integer estimation technique is used to determine the integer cycle slip vector from the float solution. Tests will be conducted on real data from different environments showing improvements with regards to geometry-free technique. Additionally, a new Doppler weighting scheme is introduced in the paper, taking into account both the speed of the vehicle and the carrier-to-noise density ratio.