Ambiguity Resolution Based on Recursive Least Squares Kalman Filtering Using Multi-epoch Carrier Phase Data

In the global positioning system(GPS) kinematic positioning,the pseudorange and carrier phase measurements are often used together to calculate the carrier phase integer ambiguity.The pseudorange information can be either a raw observation of a single epoch or a smoothed value based on multi-epoch.For the carrier phase information,traditionally only single-epoch observations are used,because the position of the GPS antenna changes continuously in kinematic applications.A new carrier phase ambiguity resolution method is proposed by using multi-epoch data for both pseudorange and carrier phase data.First,the recursive least squares method is introduced,which can build the observation equations with the information from a continuous data segment.Next,a Kalman filter based on the only ambiguity state is used to calculate the float ambiguities.Then,the cycle slip detection and repair technique in kinematic mode is discussed with special emphasis on bridging discontinuous observations.The proposed method offers an obvious computational and performance advantage.The experiment proves that the proposed method can efficiently solve the integer ambiguities in GPS kinematic positioning.