High-spin-rate roll angle measurement method based on GPS using single patch antenna

The Global Positioning System (GPS) signals-based roll angle measurement methods are key technologies for spinning vehicles with side-mounted single patch antenna. Most existing research focuses on attitude measurement at low spin rates, and it is difficult to achieve accurate roll angle measurement at a time-varying situation with high spin rates, and the attitude measurement errors are not modeled and analyzed. A multi-channel roll angle measurement method based on a third-order phase-locked loop is proposed to improve the attitude measurement accuracy and stability. The effects of phase-locked loop (PLL) tracking errors, errors induced by antenna gain, and antenna phase center offset errors are analyzed and verified by simulation. The intermediate frequency (IF) GPS signals received by a single patch antenna are sampled on a testbed to verify the roll angle measurement method. The experiment results show that the root-mean-square error (RMSE) of the roll angle measurement is 5° ± 1° at spin rates ranging from 50 to 200 r/s.