One Pseudo-satellite/GNSS Combined Indoor and Outdoor Fusion Positioning Method Based on Carrier Phase Measurement

Background: In order to realize seamless indoor and outdoor positioning, the positioning results of multiple positioning methods are taken into consideration, and a seamless indoor and outdoor positioning method that ignores the differences in indoor and outdoor environments is required now. Objective: The implementation of Pseudo satellite/GNSS combined indoor and outdoor fusion positioning for seamless indoor and outdoor environment positioning. Results: This algorithm achieves a fixed ambiguity pseudo satellite/GNSS accuracy of better than 0.15 meters in low-density buildings where there are more than 7 GNSS satellites. When there are fewer than 4 GNSS satellites and the positions is severely obstructed, GNSS alone cannot realize the position, but with the support of pseudo satellites, the accuracy of position can be better than 0.3m. Even without GNSS and only 4 pseudo satellites, the accuracy of position can still be better than 0.5 m. Methods: An adaptive federated filter is needed for this environment, which can dynamically adjust the information allocation parameters and measurement noise of the sub-filters in the federated filters based on positioning data. It adopts multi-sensor fusion filter to design a seamless indoor and outdoor positioning method. Different positioning data is fused through federated filtering, ultimately seamless indoor and outdoor positioning is realized. Conclusion: The relevant experimental results indicate that the method proposed can be used for practical applications of indoor and outdoor fusion positioning