Carrier phase estimation in real-time Global Navigation Satellite System (GNSS) receivers is usually performed by tracking loops\r\ndue to their very low computational complexity. We show that a careful design of these loops allows them to operate properly\r\nin high-dynamics environments, that is, accelerations up to 40 g or more. Their phase and frequency discriminators and loop\r\nfilter are derived considering the digital nature of the loop inputs. Based on these ideas, we propose a new loop structure named\r\nUnambiguous Frequency-Aided Phase-Locked Loop (UFA-PLL). In terms of tracking capacity and noise resistance UFA-PLL has\r\nthe same advantages of frequently used coupled-loop schemes, but it is simpler to design and to implement. Moreover, it can keep\r\nphase lock in situations where other loops cannot. The loop design is completed selecting the correlation time and loop bandwidth\r\nthat minimize the pull-out probability, without relying on typical rules of thumb. Optimal and efficient ways to smooth the phase\r\nestimates are also presented. Hence, high-quality phase measurementsââ?¬â?usually exploited in offline and quasistatic applicationsââ?¬â?\r\nbecome practical for real-time and high-dynamics receivers. Experiments with fixed-point implementations of the proposed loops\r\nand actual radio signals are also shown.
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