Geometry-free and non-geometry-free testing quantities for cycle slip detection and correction in case of strong atmospheric variations with static observations

Abstract

Cycle slip detection and correction is an important part of GPS data processing. In the past research, geometry-free and non-geometry-free testing quantities have been proposed. Both of them can be used for static cases. Each of them has their own advantages and disadvantages. This research is aiming to compare these two kinds of testing quantities for static cycle slip detection and correction in different situations, such as in low and high elevation angles, especially in cases of strong atmospheric variations. The performance of geometry-free and non-geometry-free testing quantities is compared with observations of different situations. The numerical results show that the effect of the rapid change of relative humidity on cycle slip detection and correction with these two kinds of testing quantity is not obvious. However, the results clearly show that in the case of a low elevation angle (<10°), non-geometry-free is obviously a better choice. In the case of ionospheric scintillation, geometry-free testing quantity can no longer be used. With non-geometry-free testing quantity, cycle slips can be detected and corrected successfully, if the number of continuous cycle slips is small for example, less than 5.

Keywords:

• GPS
• Ionospheric scintillation
• Cycle slip detection and correction

Acknowledgements

The research was substantially supported by the Fundamental Research Funds for the Central Universities (grant no. 14CX02036A, 14CX02033A and 14CX02039A), funded by Hong Kong RGC General Research fund (A/C: PolyU 5131/10E), National Natural Science Foundation of China (grant nos. 40974004, 41274011 and 41001250) and Natural Science Foundation of Shandong Province, China (grant no. ZR2012DM010 and ZR2011DQ011).