Improving Low-Cost GNSS Receiver Carrier Phase Tracking for High Precision Applications
Low-cost Global Navigation Satellite System (GNSS) receivers capable of high precision positioning have drawn increased attentions due to strong application demands. High-precision positioning techniques, such as Real-Time Kinematic and Precise Point Positioning, require the use of carrier phase measurements. High precision positioning solution however is currently not available in most low-cost GNSS receivers in harsh environments due to the poor quality of carrier phase measurements limited by the antenna and the oscillator quality and the lack of proper tracking algorithms. The research in this thesis aims at solving several challenging issues of carrier phase tracking of low-cost GNSS receivers. To improve carrier phase tracking sensitivity performance, a joint vector phase lock loop (VPLL) architecture is proposed and implemented in a software receiver. The transfer function model of the joint VPLL is analysed. To assess the sensitivity performance, a simulator test is conducted and the results show that the carrier phase tracking sensitivity using the proposed method is improved about 6 dB. The influence of vibration-induced oscillator phase noise on carrier phase tracking is analysed. Using hardware simulator and field tests, the performance of both the joint VPLL and scalar tracking are analysed and compared under oscillator vibration conditions. The results show that the proposed joint VPLL can improve the robustness of the carrier phase tracking compared to the scalar PLL. The performance of the joint VPLL in carrier phase prediction and tracking sensitivity is further investigated under kinematic mode. The phase prediction method based on the joint VPLL is implemented and its performance is compared with a conventional prediction strategy. A field vehicle test shows that the prediction performance of the proposed method is much better. The sensitivity of the joint VPLL under kinematic mode is analysed and compared with the scalar tracking. Based on the characteristics of the joint VPLL, an adaptive joint VPLL has been proposed for high dynamic applications. The performance of the proposed adaptive joint VPLL is analyzed with a simulation and a field test. The results demonstrate the better performance of the proposed adaptive joint VPLL compared to the joint VPLL without adaptive techniques.
Engineering--Aerospace, Engineering--Electronics and Electrical
Chen, S. (2017). Improving Low-Cost GNSS Receiver Carrier Phase Tracking for High Precision Applications (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/26491