Single-base station positioning for photovoltaic power plant inspection UAVs based on PPP-B2b signal

Aiming at the situation where photovoltaic power stations in remote areas suffer from poor communication networks, which makes reliable acquisition of satellite precise orbit data and clock offset data unattainable, this paper employs PPP-B2b combined with broadcast ephemeris to obtain precise orbit and clock offset data. To address the impact of multipath errors during inspection missions, this study focuses on analyzing the influence of pseudorange multipath errors on observation values at different frequency points, as well as the relationship between observation data quality and multipath errors. The linear combination method utilizing multi-frequency carrier phase and pseudorange observations is applied to mitigate pseudorange multipath errors. Experimental results demonstrate that after correction, static positioning accuracy improved by 6.58%, 10.28%, and 11.96% in the E, N, and U directions respectively, while dynamic positioning accuracy showed enhancements of 9.82%, 10.06%, and 10.41% in the corresponding directions. Validation through hardware testing platform experiments confirms the method's applicability in the specified environmental conditions. Compared with traditional precise point positioning methods, this approach enables high-precision single-station positioning without reliance on communication networks. Subsequent pseudorange multipath error correction further enhances positioning accuracy for inspection UAVs.