Galileo Quasi-Pilot Signals: Starting the Era of Second Generation Galileo Signals on First Generation Satellites

S. Wallner, J. Hahn, J.A. Garcia-Molina, G. Lopez-Risueno, M. Caparrini, M. Lopez, M. Paonni, M. Dotzauer, F. Formaggio

Abstract:	The capability to acquire GNSS signals at low complexity is identified by major chipset manufacturers as an essential discriminator, in view of the emerging Snapshot and Internet of Things (IoT) Devices. To fulfill this need, the Galileo Program is developing new solutions with the Quasi Pilot (QP) Signals [2], [3]. Tests of an early Quasi Pilot signal component in the E5 band onboard existing Galileo 1st Generation (G1) Full Operation Capability (FOC) satellites, referred to as E5a-QP have been conducted as of 2023. During the test campaign an intensive consultation with receiver, chipset and Radio Frequency Constellation Simulator (RFCS) manufacturers was conducted to collect feedback on such signal. Obviously, the E5a-QP signal design is constrained to be compatible with the existing FOC payload design, that has been defined without the condition of hosting such additional signal component in the E5 band. This paper reports on the tests of the E5a-QP signal component conducted on Galileo FOC satellites GSAT0201 and GSAT0202. The paper does identify details about the signal configuration of the new signal component together with an assessment of the Signal in Space (SIS) quality of the legacy signal components (E5a, E5b) and the new E5a-QP signal component, measured in S-Curve Bias, Code-Code-Coherency and Correlation Loss based on real measurements from the two satellites in orbit. Details regarding the re-allocation of power to all signal components are provided. The E5a-QP signal has already been implemented in some receivers that are available to the Galileo program. The receiver acquisition process tailored for this new signal component is outlined, giving evidence on the reduced computational complexity compared to legacy signals. After the direct acquisition of the E5a-QP component, the receiver can transfer in acquisition to the legacy signals (here E5a-Q) - possible methods for the hand-over process from the acquired QP signal component to the legacy E5a-Q component are outlined. The added value of the new signal component is characterized based on live measurements in open sky and urban environment, which do indeed show an approximately three times faster acquisition compared to E5a-Q.
Published in:	Proceedings of the 38th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2025) September 8 - 12, 2025 Hilton Baltimore Inner Harbor Baltimore, Maryland
Pages:	849 - 861
Cite this article:	Wallner, S., Hahn, J., Garcia-Molina, J.A., Lopez-Risueno, G., Caparrini, M., Lopez, M., Paonni, M., Dotzauer, M., Formaggio, F., "Galileo Quasi-Pilot Signals: Starting the Era of Second Generation Galileo Signals on First Generation Satellites," Proceedings of the 38th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2025), Baltimore, Maryland, September 2025, pp. 849-861. https://doi.org/10.33012/2025.20402
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In