We are excited to announce our next Alberta ION lecture series, where Dr. Daniele Borio will present their work on GNSS meta signal processing. This will be a virtually hosted meeting.
Title: GNSS Meta-Signals: from Signal Processing to Carrier Phase Ambiguity Resolution
Author: Daniele Borio, European Commission, Joint Research Centre
Dr. Daniele Borio is a scientific technical officer in the “Land and Climate” unit of the European Commission (EC) Joint Research Centre (JRC), Ispra, Italy.
His research interests include the fields of digital signal processing, location and navigation with specific emphasis on Global Navigation Satellite Systems (GNSS).
Dr. Borio has been developing the theory and practice of GNSS meta-signals and his contributions were recognized by the US Institute of Navigation (ION) with the 2025 Thurlow Award and the 2023 Burka Award. Since 2013, Dr. Borio has been contributing to the ESA/JRC International Summer School on GNSS, providing lectures on GNSS threats and organizing labs on GNSS signal processing. The research activities of Dr. Borio led to the publication of more than 70 peer-reviewed journal papers and more than 100 conference papers.
From January 2008 to September 2010, Dr Borio was a senior research associate at the University of Calgary, Canada. He received the M.S. degree in Communications Engineering from Politecnico di Torino, Italy, the M.S. in Electronics Engineering from ENSERG/INPG of Grenoble, France, and his PhD in electrical engineering from Politecnico di Torino in April 2008.
Abstract:
A Global Navigation Satellite System (GNSS) meta-signal is obtained when at least two GNSS signal components, broadcast on different frequencies, are jointly processed as a single entity. This concept was originally introduced for wide-band signals such as the Galileo Alternative Binary Offset Carrier (AltBOC), which is obtained by combining the E5a and E5b signals. These components can be processed independently using standard methods already available for legacy signals such as the GPS L1 Coarse/Acquisition (C/A) modulation and used to generate independent measurements for both the E5a (1176.45 MHz) and E5b (1207.14 MHz) frequencies.
While independent processing offers implementation efficiency, it does not fully exploit the benefits of a wide-band modulation such as the AltBOC, which enables highly accurate pseudorange estimation. A possibility is to combine measurements from the E5a and E5b components and reconstruct in a synthetic way, i.e. without requiring modifications at the receiver signal processing stage, AltBOC carrier phases and pseudoranges. This presentation demonstrates that this approach is strictly related to the narrow- and wide-lane dual-frequency combinations, which need to be formed for the meta-signal measurement reconstruction. Specifically, integer cycle ambiguities must to be solved for the wide-lane carrier phase combination, which is then used for the reconstruction of AltBOC pseudoranges. Ambiguity resolution is performed using the Hatch-Melbourne-Wübbena combination, which naturally arises in the synthetic meta-signal paradigm. The narrow-lane dual-frequency carrier phase combination is used for the reconstruction of AltBOC carrier phase measurements through a half-cycle ambiguity resolution process. This reveals that narrow- and wide-lane carrier ambiguities are strictly related through parity constraints, a relationship that can be leveraged in traditional carrier phase processing.
When considering high-order meta-signals, which involve components from more than two frequencies, concepts developed in the context of Three-Carrier Ambiguity Resolution (TCAR) and Four Carrier Ambiguity Resolution (FCAR) emerge. In these approaches, carrier integer ambiguities are solved in a cascaded way considering linear combinations with progressively decreasing wavelengths. For instance, extra-wide-lane combinations are introduced to facilitate single-epoch ambiguity resolution. These concepts naturally emerge when dealing with meta-signals with more than two components. This presentation reviews the synthetic meta-signal approach and reinterprets standard concepts such as linear measurement combinations with respect to the properties of GNSS meta-signals. For instance the concept of signal subcarrier, already emerging with the Binary Carrier Offset (BOC) modulation, is linked with the wide-lane carrier combination. This illustrates once more how the different GNSS receiver processing levels are strictly intertwined, showing that concepts arising in one domain, for instance at the signal processing stage, find their counterpart in other domains, such as the measurement processing stage.
Please contact a member of the executive if you would like to attend and did not receive the meeting link through the mailing list
Date: Tuesday, April 14, 2026
Time: Meeting will open at 11:45am, presentations to begin shortly after 12:00
Cost: Free