An Insight on Mass Market Receivers Algorithms and their Performance with Galileo OS

The scope of the work is the development and demonstration of the main GNSS algorithms currently used in mass-market GNSS receivers, by focusing on a GPS and Galileo consumer receiver. Indeed, the global market for commercial GNSS chipsets continue to rapidly grow. In the next future. when more constellations are available, the constellations selection may be driven by particular signal characteristics that can result helpful features. Thanks to the release of the Galileo ICD in 2010, Galileo capable chips have been developed well in advance and at present there are several consumer devices ready to process Galileo signals with just a firmware update, for example the STM Teseo 2. An exhaustive survey on existing mass-market signal processing techniques has been carried out; the most promising state-of-the-art algorithms for GPS signals have been analyzed, implemented in a software receiver and extended to E1BC Galileo signals. The performance of these techniques in terms of code delay and Doppler frequency estimates has been verified with simulated GNSS data. At the same time, three main mass-market design drivers have been identified, studied with the software receiver and tested with the Teseo 2. First the TTFF for different C/N0, for hot, warm and cold start, and for different constellation combinations has been computed. Then some tests on the sensitivity in harsh environments have been carried out, exploiting a simulated LMS channel and different user dynamics. Finally, power consumption strategies, in particular duty cycle tracking, were considered. The testing activity has been conducted in the ESTEC Navigation Lab and, on-field, using a mobile test-bed vehicle. The analysis of the results spots the performance differences between the same algorithms applied to different constellation signals and provides an early assessment on the suitability of their characteristics, hereby improving the attractiveness of Galileo to the mass-market community.