Abstract: Confirmation of integer ambiguity and the detection and correction of cycle slip are important quality indices of BDS observed data. Firstly, based on the code pseudorange observation equation and carrier phase observation equation, BDS integer ambiguity resolution method is studied. Secondly, the ionospheric residual method is used to detect cycle slips, and its feasibility for BDS is analyzed by simulation. Results show that it is more suitable to detect cycle slips with ionospheric residuals when the cycle slip is less than 8 weeks; if the cycle is longer than 8 weeks, other methods should be used to detect cycel slip.

Key words: observed data quality, integer ambiguity, cycle slip, ionospheric residual