Effects of correcting ground-based phase wind-up with additional external attitude information on RTK positioning

In global navigation satellite system (GNSS) positioning, phase wind-up is an error caused by the relative motion between the receiving antenna and the satellite antenna, which is specifically characterized by interference with right-hand circularly polarized signals. When the receiver antenna rotates only around its polarization axis, the phase wind-up (PWU) effect behaves as a common-mode error and can be effectively mitigated by the double-difference model in short-baseline relative positioning. Therefore, this error is usually neglected in static short-baseline measurements and real-time kinematic (RTK) surveys. However, when the rotation direction of the vehicle-mounted antenna is inconsistent with the polarization axis, the influence of phase wind-up on positioning accuracy cannot be completely removed by the double-difference model. To address this issue, this study derives the PWU model under arbitrary antenna attitudes, introduces external attitude information for PWU compensation, and proposes an attitude-assisted ground-based phase wind-up (GPWU) correction algorithm. The experimental results show that after phase wind-up correction, the root mean square errors (RMSE) of the positioning coordinate deviations in the east, north and up directions are improved by 53%, 34% and 15% respectively.