An LUT-based Adaptive DPLL for SSV GNSS Receivers

초록

Global Navigation Satellite System (GNSS) receivers suffer low signal power and high dynamic stress to operate in the Space Service Volume (SSV). The dedicated design of receivers for challenging environments is needed. In this paper, a Look-Up Table (LUT)-based adaptive Digital Phase Locked Loop (DPLL) is proposed. It continually adjusts the noise bandwidth of the DPLL properly by measuring current C/N0 and jerk dynamic stress. Because it contains the LUT that has several pre-computed noise bandwidth values, an additional calculation process of the appropriate noise bandwidth value is not needed. Therefore, the receivers simply get the proper noise bandwidth value from LUT for the stable operation. Numerical simulations configured using the moon exploration mission trajectory show that the proposed algorithm maintained tracking of the signal parameters for the harsh environment simulation scenario including the low signal power region and the high dynamics region, while the conventional fixed noise bandwidth lost its lock.