Evaluating tracking performance and a new carrier-to-noise estimation method using SNACS

Multipath propagation is still one of the main error sources for many GNSS applications. The introduction of new GNSS signals of Galileo and the modernized GPS, for example, will provide higher signal bandwidths which alleviate the disruptive effects of multipath propagation. To study the influences of highly time-variant channels on GNSS tracking performance, simulations of various environments and signal combinations have to be considered. Many signal studies are based on correlation function simulation techniques. Yet to simulate GNSS signal processing with respect to multipath channels, the time-domain simulation approach serves as the most realistic and accurate but also as the most complex and computationally demanding method. This paper presents the further development of the time-domain GNSS simulation tool SNACS and its extension with additional modulations and GNSS coding schemes. Furthermore, a newly developed loss-of-lock detection method is presented and its performance is evaluated using SNACS.