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This study presents a novel solution of DLL discrimination function for multiband global navigation satellite systems (GNSS) receivers, designed to cope with a multipath-prone environment in safety-of-life (SoL) applications. The solution is based on a combination of squared correlators (CSC) outputs, following an approach similar to that driving to the well-known, and patented, StrobeTM discriminator. The proposed CSC discriminator features the novelty with respect to other 'double-delta' architectures, usually covered by patents, still maintaining a light implementation (four correlators per channel, plus the prompt one); this comes at the cost of sub-optimal performance with respect to the classic StrobeTM discriminator. The study presents the definition of the CSC solution in the context of a SoL receiver architecture, discusses the motivations for its design choices and shows an analysis of performance both in open-loop, basically employing the discriminator S-curve and the multipath error envelope, and in closed-loop, measuring the variance of estimated code phase and the statistics of the multipath-induced phase error. Performance of the proposed function are evaluated for the typical modulations of the GPS L1 and Galileo E1 systems, namely BPSK(1), BOC(1,1) and CBOC(6,1,1/11). [ABSTRACT FROM AUTHOR]

Many GNSS applications have been experiencing some constantly growing needs in terms of security and reliability. To address some of them, both GPS and Galileo are proposing evolutions of their legacy civil signals, embedding features of authentication. This paper focuses on the Galileo Open Signal Navigation Message Authentication (OSNMA) and describes its implementation within a real-time software receiver for ARM-based embedded platforms. The innovative contributions of the paper include the software profiling analysis for the OSNMA add on, along with the comparison among performances obtained with different platforms. In addition, specific evaluations on the computational load of the whole receiver complete the analysis. The receiver used for the implementation belongs to the NGene receivers family-real-time fully-software GPS and Galileo receivers, tailored for different platforms and sharing the same core processing. In detail, the paper deals with the introduction of the OSNMA support inside the eNGene, the version of the receiver executable by ARM-based embedded platforms.