Comparative Analysis of SNR Meters in GNSS Receivers

The main algorithms for measuring the carrier-to-noise density ratio (C/N0) of signals from global satellite navigation systems (GNSS) are considered, including well-known algorithms that require minimal a priori information about signals (robust algorithms), and less well-known, but more promising noise-immune algorithms that require to obtain some preliminary information. Ways of obtaining this a priori information are considered. Two types of robust and noise-immune algorithms have been analyzed in the paper. One type (for low dynamic applications) uses only the in-phase I component of the input signal, and the second (for high dynamic applications) uses a combination of the in-phase I component and quadrature Q component (Z
²
=I
²
+Q
²
). Simulation modeling and full-scale experiments are used to analyze the algorithms.