Abstract：Aiming at the characteristic that Beidou-3 satellites can broadcast four-frequency signals, we propose a real-time cycle slip detection and repair method. The method combines three geometry-free phase combinations and one code-phase combination. Firstly, the high-quality geometry-free combination under multi-frequency conditions is discussed, and then three geometry-free phase combinations and one code-phase combination are selected to detect the cycle slips, combined with the LAMBDA method to repair the cycle slips in real time. Finally, we use the measured data under the different observation conditions to verify the effectiveness of the proposed method. The results show that the method is less affected by ionospheric delay than three-frequency condition, and can detect and repair the cycle slips in real time.
