Africa records about 3% of global air traffic, and yet air accidents in Africa account for roughly 20% of the worldwide total. In a bid to adopt the best safety standards and strengthen the continent’s navigation and positioning applications, African leaders are looking to develop Satellite Based Augmentation Systems (SBAS).
Currently, global powers maintain huge investment in the Global Navigation Satellite Systems (GNSS) core constellations such as the GPS (U.S), Beidou (China), Russia’s GLONASS and Europe’s Galileo. However, when used alone, GNSS constellations have several limitations in the application areas where more integrity, availability, continuity and accuracy (less than 10) are required.
To supplement the shortfalls of GNSS core constellations, governments and companies developed SBAS networks with optimized usage and defined coverage area. The network augments core GNSS constellations through the use of geostationary (GEO) satellites which broadcast the augmentation information to improve ranging, integrity and correction data. While the main goal of SBAS is to provide integrity assurance, it also increases the accuracy with position errors below 1 meter, making it compliant with the stringent requirements of specialised applications such as the operational requirements set by the International Civil Aviation Organization (ICAO) for use during the most critical phases of aircraft flight, in particular, final approaches.
SBAS has been implemented or is undergoing implementation in several parts of the world, for example, WAAS (US), EGNOS (Europe), MSAS (JAPAN); GAGAN (India) SDCM (Russia), KASS (South Korea), BDSBAS (China), AUSBAS (Australia/NZ) and SBAS for Africa and Indian Ocean (ASECNA).
In Africa, the ‘EGNOS in Africa Support Programme’, a partnership between Africa and the European Union, is championing a roadmap for the development of GNSS applications and implementation of EGNOS services across the continent.
Although the Africa-EU relations in the domain of Satellite Navigation in Africa started earlier with bilateral collaborations between the European Union and a couple of individual African states and regional bodies to support initiatives in Africa, the ‘EGNOS in Africa Support Programme’ was enabled through the EU 2011-2013 Action Plan “Support to the Air Transport Sector and Satellite Navigation in Africa” Programme which introduced the SAFIR (Satellite Navigation Services for African Region) and its training arm TREGA (Training on EGNOS-GNSS in Africa) projects.
In an exclusive interview with Space in Africa, the ‘EGNOS in Africa Support Programme’ s Joint Programme Office (JPO) Director, Semou Diouf, discusses the EGNOS in Africa Support Programme and other on-going GNSS/SBAS initiatives in Africa.
According to Diouf, the EGNOS in Africa Support Programme has been implemented through different phases since 2013. The first phase focused on building capacity on GNSS/EGNOS in Africa, and establishing close relationship with relevant stakeholders such as the African Union Commission (AUC), the Regional Economic Commissions (RECs), African Civil Aviation Commission (AFCAC), International Civil Aviation Organization (ICAO), Civil aviation authorities, , air navigation service providers, other organisations in sectors outside aviation sector.
In collaboration with the aforementioned partners, JPO developed earlier in 2015 a roadmap for the provision of GNSS/EGNOS services in Africa. and proposed a modular approach for its implementation based on the Regional Economic Community’s (RECs) delimitation. The roadmap outlined the implementation of the programme across four modules: Eastern, Northern, Western and Central, and Southern Africa, to be championed by the respective regional economic commissions and relevant stakeholders.
Following the development of the roadmap, what Diouf described as the “post-SAFIR period”, JPO has focused on implementing the programme through MoU (memorandum of understanding) with RECs and scaling awareness of the use of satellite navigation technology among relevant decision-makers across the continent.
To help guide its operations and validate the implementation of the programme, a steering committee was set up, jointly chaired by the African Union Commission (AUC) and the European Commission. Membership of the Steering Committee comprises the RECs, aviation authorities and other relevant stakeholders. JPO, which is hosted by the Agency for Aerial Navigation Safety in Africa and Madagascar (ASECNA), acts as the secretariat with a team of about 10 African experts who were competitively recruited to implement the programme.
Commenting on the relationship between JPO and ASECNA, Diouf said the “programme is managed by ASECNA for administrative and financial aspects”. as part of its contractual obligations.
As every similar programme requires funding, this begets the question of how is the programme funded? Diouf notes that the EGNOS in Africa Support Programme is currently funded by the EU through the Pan-African (PanAf) Programme, one of the major financial instruments of implementation of the Joint Africa-EU Strategy (JAES) adopted at the 4th Africa-EU Summit held in Brussels on April 2014. The Annual Action Programme 2015, which is co-funded by EC and ASECNA, also included the EGNOS in Africa Support Programme with its operations referred to as “Support to the Joint Programme Office (JPO)”.
The funding for the programme is structured to cover the staffing of the JPO, administration and management costs, as well as capacity building activities such as workshops organised in respect of the programme.
“I should also mention that there is no SBAS/EGNOS infrastructure costs incurred by the Programme itself as the funding of the SBAS/EGNOS infrastructure will be under the responsibility of the states and regional initiatives which are ready to implement SBAS services in their areas of responsibility,” Diouf explained.
Status of GNSS/SBAS Infrastructure in Africa.
GNSS infrastructure in Africa is largely organised around GNSS Continuously Operating Reference Station (CORS), used predominantly for surveying and mapping applications, with several CORS already deployed in over 15 African countries mainly in the COMESA (Common Market for Eastern and Southern Africa) and SADC (Southern African Development Community) regions. South Africa alone has over 67 operating base stations that form the country’s TrigNet network, according to a 2014 record.
South Africa also hosts GNSS data processing centres with capacity for several GNSS core satellites. The Regional Centre For Mapping Resource For Development (RCMRD) in Kenya houses another GNSS data processing centre in Africa.
Concerning GNSS infrastructure, Diouf noted an upward trend towards the “densification of GNSS CORS” as more countries continue to adopt Spatial Data Infrastructure (SDI) initiatives.
“Besides the deployment of GNSS CORS, many stand-alone reference stations have been deployed mainly for scientific research initiatives, though such initiatives are funded by entities outside Africa,” he added.
For SBAS infrastructure, Africa is still at the preliminary stages of deployment of such technology, with a scarce number of fledgeling initiatives across the continent.
Some notable efforts towards the development of SBAS technology include programmes led by ASECNA and the South African Space Agency (SANSA).
In 2014, ASECNA, French space agency CNES (Centre National d’Etudes Spatiales) and the European Space Agency, with support from a French company Thales Alenia, deployed GNSS sensors covering the Western Africa Region known as SAGAIE, to investigate the ionospheric effects on GNSS signal propagation in the Equatorial ionosphere. Data from the SAGAIE analysis demonstrated the feasibility of SBAS service in the equatorial region, and was later integrated into the European Ionospheric Monitoring Experimentation Plan & Instrument Development (MONITOR), which was started in 2010 to monitor and characterize the ionospheric effects on the performance of Galileo and EGNOS systems in extreme events.
Both ‘MONITOR’ and ‘SAGAIE’ are pre-requisite to SBAS deployment in the ASECNA coverage region. SAGAIE stations are already installed in major airports of the region: Dakar, Lomé, Ouagadougou, Douala and N’Djamena.
Also, ASECNA in collaboration with the EU and Thales Alenia performed SBAS demonstration known as MAGNIFIC (Multiplying In Africa European Global Navigation Initiatives), to test EGNOS and Galileo Services “through benefits that spread much beyond civil aviation needs,” targeting its coverage region. MAGNIFIC cost a total of €2 million, with the EU contributing 70% (€1.4 million) of the total cost.
More recently, ASECNA accelerates it SBAS programme, so-called “SBAS for Africa and Indian Ocean”, with the objective of SBAS services provision in the 16 million square kilometres single sky airspace under its responsibility, and potentially beyond in Africa, as per the mandate given by its 18 Member States.
Recognised by the International Civil Aviation Organisation, this ASECNA programme pursues the autonomous provision of initial services from the 2021/2022 time horizon, to enhance navigation and surveillance operations for all phase of flight, from en-route down to approach, for the benefit of its airspace users. A pre-operational SBAS service will be provided in 2020 in western and central African, to showcase the benefits and easy-of-use of SBAS applications and to initiate the deployment of the full system architecture.
Another SBAS demonstration in Africa, known as ‘SBAS-Africa’, was made possible by a collaboration between the South African National Space Agency (SANSA) and the UK Space Agency (UKSA). SBAS-Africa is led by UK’s Avanti Communications Plc and co-funded by the UK Space Agency (UKSA) under the International Partnership Space Programme (IPSP).
The SBAS-Africa project has “delivered a live SBAS signal in space serving the southern part of the African continent. The system generated SBAS messages using GMV’s magicSBAS tool suite with input data from a network of GPS ground monitoring stations developed by NSL which are deployed across South Africa and neighbouring countries. The messages were broadcasted via the ARTEMIS satellite originally an ESA EGNOS test satellite which is now owned and operated by Avanti,” according to a project outcome report published by the project team.
‘SBAS-Africa’ pilot testbed achieved the following results:
- 1-metre horizontal accuracy SBAS test services for Southern and Eastern Africa.
- Service demonstration and user trials for aviation, maritime and agriculture sectors.
- A draft capital project appraisal and transition plan for SBAS in South Africa.
- A basis for extension to southern African neighbouring states and build-up of capacity in the region.
A preliminary business case produced by the demonstration promises to deliver “R15.6 billion (USD 1.1 billion) [discounted] to the South African economy over 25 years with a return on investment of better than 10:1.” The demonstration further ties into the South African SBAS strategy for the SADC countries.
Meanwhile, South Africa’s Durban University of Technology (DUT) and CNS Systems (Pty) Ltd – a commercial company run by the leader of the Space Science Programme at DUT, Professor Dimov Stojce Ilcev; has proposed the development of African Satellite Augmentation System (ASAS). ASAS hopes to develop a “truly pan-African SBAS” with indigenous ground technologies and the possibility to use GEO space segment, the same used by EGNOS, such as Inmarsat and Artemis satellites. With an estimated total cost of USD 150 – 300 million, (DUT) and CNS Systems have not raised the required fund to pilot the project beyond the design phase.
Up in North Africa, EGNOS coverage already extends to the region under the Mediterranean Follow-Up for EGNOS Adoption (MEDUSA) programme within the framework of the European Neighbourhood Policy (ENP) cooperation. African countries covered by the MEDUSA programme include Algeria, Egypt, Libya, Morocco and Tunisia.
Commenting on SBAS in North Africa, Diouf said: “SBAS infrastructure (Reference Stations) has its presence in Africa, mainly for purposes of supporting the SBAS services in Europe, but also to cover, to some extent, some part of Africa, namely Northern Africa (Algeria, Tunisia, Libya, Egypt, and Morocco).”
The Algerian Space Agency in December 2017 launched an SBAS payload onboard AlComSat-1 GEO communications satellite. The testing of the payload was initially planned for June 2019 [Space in Africa is yet to confirm the status of the test].
Similarly, Nigeria owns an SBAS payload onboard NigComSat-1R communications satellite which was launched in 2011 as a replacement for the country’s first GEO satellite that failed in 2007 in orbit after running out of power due to an anomaly in its solar array.
On December 2018, Nigerian communications satellite operator NIGCOMSAT Ltd signed an agreement to collaborate with Thales Alenia on the Testbed Experimentation of the Nigeria Satellite Augmentation System (NSAS).
NSAS will make “differential corrections and then broadcast the integrity messages as an augmented signal of the original GNSS Signal in Space (SiS) through NigComSat-1R for wide coverage,” notes Dr Salami Lasisi Lawal, NIGCOMSAT Head of Department, Navigation Services.
Other SBAS initiatives in Africa include the Eastern Africa SBAS ‘Module’ led by COMESA, the East African Community (EAC) and the Intergovernmental Authority on Development (IGAD), with support from JPO. On the request of COMESA, EAC and IGAD, JPO successfully carried out a preliminary programme proposal for the Eastern Africa SBAS module for the relevant stakeholders’ consideration. The proposal covers the implementation of SBAS in 12 East African countries targeting aviation, precision agriculture and container inventory management in ports.
While the proliferation of several SBAS initiatives on the continent raises questions of coordination and possible redundancy, Diouf thinks of the situation from a different perspective.
“The main reason for these [proliferation of] different initiatives lays in the level of readiness of states and regions. However, the end goal for Africa would be ideally an indigenous Single African SBAS to be in line with the African Union Space Policy and Strategy and the concept of no country left behind.
To the question on overlapping issues, Diouf answered that this will be addressed through interoperability between the systems providers if the case happens.
The African Union further underscores the importance of functional satellite navigation and positioning infrastructure in Africa as depicted in the objectives of the AU Space and Policy Strategy and the AIM Strategy 2050 for the maritime economy adopted in 2016 by the 26th AU Summit and is entrenched in the Agenda 2063 development horizon.
AUC commissioned JPO in 2018 to conduct a continent-wide survey on satellite navigation and positioning in Africa in view of gaining insight for the development of GNSS/SBAS technology and infrastructure that will benefit the continent.