7 research outputs found
Design of Short Synchronization Codes for Use in Future GNSS System
The prolific growth in civilian GNSS market initiated the modernization of GPS and the GLONASS systems in addition to the potential deployment of Galileo and Compass GNSS system.The modernization efforts include numerous signal structure innovations to ensure better performances over legacy GNSS system. The adoption of secondary short synchronization codes is one among these innovations that play an important role in spectral separation, bit synchronization, and narrowband interference protection. In this paper, we present a short synchronization code design based on the optimization of judiciously selected performance criteria. The new synchronization codes were obtained for lengths up to 30 bits through exhaustive search and are characterized by optimal periodic correlation. More importantly, the presence of better synchronization codes over standardized GPS and Galileo codes corroborates the benefits and the need for short synchronization code design.Peer Reviewe
Design of Short Synchronization Codes for Use in Future GNSS System
YesFunding provided by the Open Access Authors Fund
Opportunities and challenges for multi-constellation, multi-frequency automotive GNSS receivers
In this paper, the implementation of a multi-constellation, multi-frequency automotive GNSS receiver is discussed. The main objective of this paper is threefold. First, to identify, in the context of automotive applications, the most promising GNSS signal combination and analyze its benefits and limitations. Second, to propose a receiver architecture that offers sufficient robustness and flexibility to maintain high-accuracy and high-availability navigation capabilities in challenging automotive signal environments as well as to accommodate the particulars of the legacy, new and modernized signals. Third, to optimize the receiver's implementation so that it meets the automotive requirements in terms of size, cost and power consumption. To this end, several front-end architectures are compared and some key aspects of the baseband hardware implementation discussed. Additionally, robust acquisition and tracking algorithms that respectively account for the availability of a second frequency and for the introduction of advanced modulations are presented. Finally, some insights are provided regarding optimization of the PVT performance in terms of multipath mitigation and ionospheric corrections
Requirements and Analysis for a Robust E1 Galileo Tracking Algorithm in the Scope of the GAMMA-A Project
FP7 GAMMA-A project is a European project with the objective to develop a 3-frequency GPS/Galileo receiver concept for automotive mass-market applications. This receiver shall build on the excellent properties of the new and modernized wide-band Galileo and GPS signals to deliver high-accuracy and robust navigation and positioning. The MBOC modulation was specially designed to improve GPS and Galileo inter-operability and tracking performance at the E1 frequency. Therefore, a different tracking architecture is required to fully benefit from this modulation, and minimize the errors caused by thermal noise and multipath. This paper focuses on the Galileo’s MBOC realization, implemented on the E1 signal, and how it impacts both receiver architecture and tracking performance. In addition, this paper provides some comments and analysis on backward compatibility with pure BOC(1,1) receivers as well as on possible data/pilot combining algorithms. The work presented here was performed in the scope of the GAMMA-A project and investigates E1 Galileo signal tracking architecture. The scope of the investigated tracking schemes was limited by hardware considerations and constraints. The proposed tracking schemes are compared and analyzed, and the most suitable E1 tracking algorithm is selected and presented with respect to the minimization of the relevant metrics in tracking stage as code tracking error and multipath error