Abstract:To make full use of the advantages of BDS-3 quad-frequency observation information, we develop a cycle-slip detection and repair method for quad-frequency observations. First, we properly select the combination coefficients of the geometry-free phase combination and geometry-free ionosphere-free combination. We combine three geometry-free phase combinations as well as one geometry-free ionosphere-free combination to detect different cycle slips. Then, we use the least-square method to estimate the cycle-slip float solutions. Finally, we adopt the LAMBDA method to further obtain the cycle-slip integer solutions. The BDS-3 quad-frequency observation data verifies that the proposed method can effectively and quickly identify various cycle slips and repair them.