GPS World

Tag: Galileo ICD

  • New Galileo Interface Control Document released

    The European Commission has published a new release 1.2 of the Galileo Open Service Signal In Space Interface Control Document (OS SIS ICD v1.2). The document provides the information needed by receiver and chipset manufacturers, application developers and service providers to process and make use of the open signals generated by the Galileo satellites.

    The OS SIS ICD contains the publicly available information on the Galileo Open Service Signal In Space, specifying the interface between the Galileo space and user segments. The Galileo user segment is of particular interest to the European GNSS Agency (GSA), which has been delegated responsibility for the program’s service provision by the European Commission.

    In fulfillment of this role, the GSA is developing the European GNSS Service Centre (GSC), which provides the single interface for information and help to users of the Galileo Open Service (OS).

    Once fully developed, the GSC will operate on a 24/7 basis and offer a range of services, including hosting the Galileo User Helpdesk, providing the interfaces between the Galileo System and OS users, and hosting a center of expertise for OS service aspects.

    The OS SIS ICD is a key document that provides the information required by receiver and chipset manufacturers, application developers and service providers to be able to process the Open Service signals generated by the Galileo satellites. In particular, the document specifies:

    • Galileo signal characteristics
    • Characteristics of Galileo spreading codes
    • Galileo message structure
    • Message data contents

    The latest version is based on feedback from receiver manufacturers and other stakeholders received during an extensive public consultation in 2014.

    The GSA further highlights the importance of this document for the development of receiver technology, which is the key enabler for translating Galileo signals into useful services. Over the past several years, the GSA has been engaged in open dialogue with chipset and receiver manufacturers, paving the way for Galileo to be fully integrated into a new generation of receivers and ensuring its signals will provide a wide array of new applications and services that directly benefit European citizens.

    In addition to a number of minor editorial improvements including corrections and clarifications, an annex with numerical examples of FEC coding and interleaving has been added and the license agreement has been revised and simplified.

    The document now refers to a companion document, “Ionospheric Correction Algorithm for Galileo Single Frequency Users,” containing details on the ionospheric model used for Galileo. The E1-B, E1-C and E5 Primary Codes in Annex C are no longer included in the paper version, but are available in the electronic version of the ICD.

    Download the ICD here. Paper copies are available on request by contacting the European Commission [email protected].

  • Galileo Open Service ICD Released, Comments Sought

    A new draft version of the Galileo Open Service Signal in Space Interface Control Document (OS SIS ICD), issue 1, revision 2, was published by the European Commission (EC) on June 30, and is available for download.

    The European Commission has launched an open public consultation process in order to improve and consolidate the current draft document and to ensure that any further development of the Galileo OS SIS ICD takes into account the views of key GNSS stakeholders.

    The OS SIS ICD contains the publicly available information on the Galileo Signal In Space. It is intended for use by the Galileo Open Service (OS) user community and specifies the interface between the Galileo Space Segment and the Galileo User Segment.

    The public consultation process provides stakeholders with an opportunity to improve the quality and clarity of the document and to suggest new elements to be included in future versions, for instance, inclusion of multi-GNSS products and services. According to the European Commission, the public consultation process will contribute towards a smooth and rapid rollout of Galileo equipment and applications, and the earliest possible delivery of user benefits.

    Comments are being accepted until September 22, 2014; a form for submitting comments is available via a link on this page.

  • The System: Galileo ICD, Free at Last

    Galileo ICD, Free at Last

    The European Commission (EC) has published an updated Galileo Open Service Signal-In-Space Interface Control Document (OS SIS ICD) giving technical specifications and performance expectations for the future system.

    As reported by GPS World in October 2009, the EC will not charge for manufacturing licenses. No fees will be required for manufacturers to design, develop, make, or sell receivers capable of using the Galileo Open Service signal. Manufacturers are required to apply for the free licenses, which “will be provided on a non-discriminatory basis in accordance with European Union rules and international commitments.”

    The SIS ICD, a 216-page, 4 MB PDF, is available.

    To obtain a license, interested parties must e-mail to [email protected], “mentioning their request for a license agreement, which is without any exclusivity or geographical limitation.”

    In a section addressing intellectual property rights (IPR), previously the stumbling block towards free-market manufacture and sale of Galileo receivers, the release states that “The information contained in the OS SIS ICD . . .  is subject to IPR. The use of [this] information . . .  including the spreading codes which are subject to IPR, is hereby allowed for research and development and/or standardisation purposes . . . “ and, in a later section regarding commercial use, “. . .  is hereby allowed for manufacturing, distribution, commercialisation, sale of electronic devices (e.g. chipsets and receivers) and supply of Value Added Services.”

    Galileo Frequency Plan.

    SBAS Woes

    In mid-April, Intelsat announced it had lost control of its Galaxy 15 satellite that hosts the WAAS SBAS transponder used by the U.S. Federal Aviation Administration (FAA). Shortly thereafter, the FAA announced that the satellite, one of two used by WAAS, would drift out of usable orbit within two to four weeks.

    Once G-15 is out of usable orbit, WAAS will be disrupted for users in northwest Alaska. The rest of the WAAS service area — U.S., Canada, Mexico — will operate normally but will be reduced to a single point of failure with one WAAS broadcasting satellite remaining (PRN 138).

    The FAA is investigating at least two alternatives:

    • Utilize Inmarsat 3 (POR) that was previously used by WAAS before switching to Galaxy 15 in 2006. POR is located at 178°E.
    • Accelerate the testing of Inmarsat 4-F3 (PRN 133). Testing is already in progress and due to be complete in December 2010. The FAA stated that there is “potential to implement as an emergency release.”

    Neither solution is an immediate one. The FAA stated that integrating POR back into operational WAAS would take 12–16 months. The quickest solution is to accelerate the implementation of PRN 133; the FAA said it might be able to shave 1–2 months from original target date.

    The FAA stated that with only a single WAAS GEO broadcasting satellite, users may experience a temporary loss of service 3-5 times this year for up to five minutes each while WAAS Uplink Station Switchovers occur.

    GAGAN Tumbles.  A rocket carrying a satellite-based augmentation system (SBAS) satellite crashed into the Bay of Bengal, deaing a significant blow to India’s GPS-Aided Geo Augmented Navigation (GAGAN) program. The rocket was to deliver the two-ton GSAT-4, which hosted, among other things, an L-band transponder that was to broadcast GPS navigation corrections used by civil aviation and other transportation modes. GAGAN, a program that is years into development, is similar to and compatible with the U.S. WAAS, Europe’s EGNOS, and Japan’s MSAS, designed for next-generation international aviation navigation.

    The initiative was using an Indian-designed and -built cryogenic engine on a rocket for the first time. The Hindu News website reported that “India began developing the cryogenic engine as its answer to technology denial regime as the U.S. not only refused the technology but also put pressure on Russia to backtrack on its commitment to New Delhi.”