Satellite Based Augmentation System test-bed project

As part of the Australian Government's National Positioning Infrastructure (NPI) Capability, Geoscience Australia is leading a test project of a Satellite-Based Augmentation System (SBAS) for the Australasia region.

An SBAS will overcome the current gaps in mobile and radio communications and, when combined with on-ground operational infrastructure and services, will ensure that accurate positioning information can be received anytime and anywhere within Australia and New Zealand.

The two-year project will test two new satellite positioning technologies including next generation SBAS and Precise Point Positioning, which will provide positioning accuracies of several decimetres and five centimetres respectively.

The project will see Australia and New Zealand join countries such as the United States, Europe, Russia, India and Japan, which have all invested in infrastructure that delivers satellite-based corrections via an SBAS.

Positioning data is now fundamental to a range of applications and businesses worldwide. It increases our productivity, secures our safety and propels innovation; enables GPS on smartphones, provides safety-of-life navigation on aircraft, increases water efficiency on farms, helps to locate vessels in distress at sea, and supports intelligent navigation tools and advanced transport management systems that connect cities and regions.

Geoscience Australia is collaborating with Land Information New Zealand (LINZ) on the test-year project to improve the positioning capability of both countries. The New Zealand Government has contributed an additional $2 million to the initial $12 million in funding from the Australian Government.

Geoscience Australia and LINZ are working closely with the Cooperative Research Centre for Spatial Information (CRCSI) on the project. The CRCSI are overseeing the evaluation of the effectiveness of an SBAS for the region, and building expertise within government and industry on its transformative benefits.

The CRCSI has called for organisations from across the aviation, road, rail, maritime, spatial, construction, mining, utilities and agriculture sectors to participate in the test-bed. Information is available via the CRCSI website. To keep informed of the progress of the SBAS test-bed project, sign up to the NPI Capability newsletter.

Frequently asked Questions

A Satellite-Based Augmentation System (SBAS) utilises space-based and ground-based infrastructure to improve the accuracy, integrity and availability of basic Global Navigation Satellite System (GNSS) signals, such as those currently provided by the Global Positioning System (GPS).

SBAS already developed internationally include WAAS in the United States and EGNOS in Europe.

A SBAS has not been previously tested in Australia or New Zealand, although the technology is employed in countries around the world, including the United States, Europe, China, Russia, India and Japan. This test-bed will assess the application of SBAS technology and its safety, productivity, efficiency and innovation benefits to Australian and New Zealand industry and research sectors.

Testing will occur over two years and will evaluate the effectiveness and application of SBAS in nine main sectors: agriculture, aviation, construction, maritime, mining, rail, road, spatial, and utilities. The test-bed will address the specific requirements (including accuracy, integrity, availability) in applications areas in each of these industry sectors.

The SBAS test-bed will be delivered by a consortium including Geoscience Australia, Land Information New Zealand (LINZ), Lockheed Martin, GMV, Inmarsat and the Cooperative Research Centre for Spatial Information (CRCSI).

Components of the test-bed include:

  1. A L-Band satellite transmitter operated by Inmarsat;
  2. The operations of a satellite uplink capability at Uralla NSW by Lockheed Martin;
  3. A positioning correction service operated by GMV and Geoscience Australia;
  4. The development and execution of a testing program, delivered in partnership by Geoscience Australia and the CRCSI.
  5. LINZ overseeing the SBAS test-bed program in New Zealand.

First test signals will be transmitted on 1 July 2017.

The SBAS test-bed will assess three specific technologies:

  1. Single frequency service SBAS, which is equivalent to WAAS (USA SBAS) and EGNOS (Europe SBAS). This technology will improve positioning of stand-alone GPS from 5 metre accuracy to better than 1 metre accuracy.
  2. Dual frequency/Multiple Constellation SBAS. This is the so-called next generation SBAS and will exploit the recent development of a civil frequency, known as L5 for GPS and E5a for Galileo. This capability will demonstrate significant performance improvements over single frequency SBAS, particularly in regions with dynamic ionosphere.
  3. Precise Point Positioning (PPP). PPP is a method that provides highly accurately position solutions with accuracy better than 10 centimetres.

The SBAS testing is designed to achieve three main objectives:

  1. Test the performance of the technology directly in a number of industries.
  2. Test the current industry-specific requirements and how they interact with the technology.
  3. Test future industry-specific innovations that might be borne out by the technology.

Ultimately, the test-bed will help determine if Australia and New Zealand should pursue the development of an operational SBAS.

The Australian and New Zealand Governments have jointly invested in a two-year program to evaluate future positioning technology options. A collaborative project, being jointly run by Geoscience Australia, LINZ, and the CRCSI will deploy a SBAS to evaluate benefits across a range of industry sectors.

CRCSI are responsible for conducting the expression of interest process for the SBAS test-bed. Information on the SBAS test-bed Demonstrator project is available via the CRCSI website. Implementation and oversight will come through Geoscience Australia and CRCSI.

Testing will be undertaken by university, government and private sector industry organisations.

Testing is expected to be conducted throughout the land and maritime jurisdictions of Australia and New Zealand.

The single frequency (L1) SBAS service will be limited to a specific geographic coverage or Service Area (see image). Subject to ongoing performance assessments, the Service Area will be extended further to the east to include New Zealand's Chatham Islands.

The CRCSI have called for organisations from across the aviation, road, rail, maritime, spatial, construction, mining, utilities and agriculture sectors to participate in the test-bed.

Expressions of interest to participate in the SBAS test-bed can completed via the CRCSI website.

To keep informed of the progress of the SBAS test-bed project, sign up to the NPI Capability newsletter.

Proposals for supported projects will be selected on merit, as determined by a review committee.

Information about the NPI Capability will be published on our website, and included in our NPI Capability newsletter.

Information on the SBAS test-bed Demonstrator project is available via the CRCSI website.

To keep informed of the NPI Capability and its progress, sign up to the sign up to the NPI Capability newsletter.

Geoscience Australia currently operates a national Global Navigation Satellite System (GNSS) network. Data from Geoscience Australia's network, which include the AuScope GNSS array, will be provided to a computation facility which adopts GMV software, also located at Geoscience Australia. Corrections will then be sent to the Lockheed Martin Space Systems Company station at Uralla, NSW, for upload to the Inmarsat 4F1 satellite. The 4F1 satellite, orbiting at 143.5 degrees longitude, will then broadcast the corrections over the Australian region.

The SBAS test-bed will not be certified for safety-of-life use. Importantly, the test signals will not put existing services at risk, especially safety-of-life services such as aircraft navigation.

The SBAS signals are defined in the RTCA DO-229D standard. Built into the SBAS message set is a specific provision for broadcasting signals that are not authorised for safety-of-life applications. Message Type 0 declares that the signal is not to be used for safety-of-life applications.

SBAS capable avionics approved for Instrument Flight Rules (IFR) navigation are certified against the Federal Aviation Authority (FAA) TSO-C145 or TSO-C146 standards. Both of these standards adhere to DO-229D meaning IFR approved avionics are certified to honour Message Type 0. Thus, IFR SBAS capable avionics will ignore the test-bed signal. Practical demonstration of this occurred during the WAAS (USA SBAS) and EGNOS (Europe SBAS) test phase. For aviation testing a selection of avionics which have been modified (outside of certification) to ignore Message Type 0 will be used to ensure that the signal broadcast can be tested to meet official safety requirements.

Land Information New Zealand (LINZ) is the government department responsible for mapping New Zealand’s landscapes and charting New Zealand waters. They look after some of New Zealand’s iconic lakes and Crown land, and their Geographic Board assigns place names.

The Cooperative Research Centre for Spatial Information (CRCSI) is an international research and development centre set up in 2003 in Australia under the Business Cooperative Research Centres Programme. They conduct user-driven research in spatial information that addresses issues of national importance.

Lockheed Martin is a global security and aerospace supplier. During the project, it is responsible for the uplink antenna at Uralla, New South Wales, which directs the augmentation messages to an SBAS payload hosted aboard a geostationary Earth orbit satellite, owned by Inmarsat.

Inmarsat is one of the leading providers of global mobile satellite communications. For the test-bed, Inmarsat is managing the Navigation Payload on its I-4 F1 satellite, the dual-channel bent-pipe transponder, which provides mobile users with two SBAS navigation signals at both GPS L1 and L5 frequencies. The I-4 F1 satellite was the first in the world to be launched carrying a transponder capable of broadcasting SBAS signals at both GPS L1 and L5 frequencies.

GMV is one of the leading suppliers of satellite ground segment equipment. Throughout the project, it is responsible for the provision of magicSBAS - a state-of-the-art, multi-constellation, operational SBAS processors to generate the Global Navigation Satellite System (GNSS) augmentation messages.

On 1 June 2017 and PRN code 122 SBAS corrections will start transmission. These corrections (RTCA DO-229D standard) will be valid in Australia and New Zealand Region only.

On 1 August 2017 Precise Point Positioning (PPP) will be transmitted on the L1 signal.

On 1 October 2017 dual frequency, multi-constellation (DFMC) SBAS corrections will be transmitted. These corrections will be regionally valid.

The three correction services will continue to be transmitted until 31 January 2019.

GNSS and SBAS satellites are uniquely identified by a pseudorandom noise number (PRN number) which specifies the ranging codes that a satellite uses. PRN allocation must be managed internationally and close cooperation with all the GNSS/SBAS operators (GPS, Galileo, Beidou, Glonass,...). The GPS Directorate, US Air Force, coordinate PRN allocation.

The SBAS Testbed will use PRN code 122 for the GPS L1 C/A signal centred at 1575.42 MHz and L5 signal centred at 1176.45 MHz. We’ve been authorized to utilize this PRN for the period of 1 May 2017 through 31 January 2019.

The SBAS Testbed will only make use of the PRN code on the GPS L1 C/A and L5 signals. PRN code 122 on the L1C and L2C signals will be held in reserve by the GPS Directorate to prevent another system from using PRN code 122 on those signals.

L1 C/A
PRN Code Number

CA

PRN Allocations

Orbital Slot

Effective Date

G2 Delay (Chips)

Initial G2 Setting (Octal)

First 10 Chips (Octal)

122

52

0267

1510

GEOSCIENCE AUSTRALIA (INMARSAT 4F1)

143.5E

Active until Jan 2019


L5
PRN Code Number

XB Code Advance (Chips)

Initial XB Code State (Octal)

PRN Allocations

Orbital Slot

Effective Date

I5

Q5

I5

Q5

122

3023

7383

10305

17637

GEOSCIENCE AUSTRALIA (INMARSAT 4F1)

143.5E

Active until Jan 2019

Technical descriptions of these codes can be found in IS-GPS-200 (L1 C/A and L2C), IS-GPS-705 (L1C), and IS-GPS-800 (L5) at the following address: http://gps.gov/technical/icwg/


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