SBAS-Africa: A Cost Effective Southern African Solution Serving Multiple Market Sectors

Abstract

Satellite Based Augmentation System (SBAS) capabilities were pioneered by the United States of America (with WAAS) and the European Union (with EGNOS) with the aim of delivering safety-of-life navigation services to the civil aviation sector and have now been deployed by other nations including GAGAN in India and MSAS in Japan. All these nations benefit both economically and socially from improved navigation services not only in the aviation sector but also across the wide range of markets that have adopted GNSS. Nevertheless due to the differences in needs and financial situation, the countries of Africa have not had the same opportunity to take advantage of all the benefit that an SBAS can deliver. SBAS-Africa is a 12 month initiative that has successfully deployed an end-to-end SBAS testbed with a live signal in space that demonstrates the potential benefits of implementing SBAS capabilities in Southern Africa. SBAS-Africa, led by Avanti Communications PLC (Avanti) was co-funded by the United Kingdom Space Agency (UKSA) through its International Partnerships Space Programme (IPSP) programme. With the collaboration of GMV, NSL, Pildo Labs, Thales UK, the South African National Space Agency (SANSA), Ghana Council for Scientific and Industrial Research and the Agency for Aerial Navigation Safety in Africa and Madagascar (ASECNA), SBAS-Africa delivered a real-time SBAS signal for the southern part of the African continent. GNSS monitoring stations developed by NSL were deployed on the ground while communication (often in very remote locations) was assured by the Avanti high throughput satellite HYLAS 2. The SBAS messages are then generated by GMV’s magicSBAS tool and broadcast via ARTEMIS satellite - originally an ESA EGNOS test satellite which is now owned and operated by Avanti PLC. The testbed immediately improves GPS accuracy assuring integrity confidence levels and showcases many benefits across a large variety of applications within different sectors. The objectives of SBAS-Africa (http://sbas-africa.avantiplc.com/), are to capture the service provision requirements for an African SBAS, to deploy an SBAS demonstrator and run demonstrations, to under-stand the likely benefits and build operational SBAS business cases for key stakeholders and finally to identify the way forward so that South African authorities are able to make a safe bet without investing so much as it was done initially in America and Europe. One of the expected outcomes of SBAS-Africa is the acceleration in the adoption of an operational SBAS for Africa. The African SBAS needs are different, there are fewer commercial aviation movements and the major benefits are likely to be agriculture, geomatics, logistics, maritime and general aviation. But SBAS does not only bring economic benefits, it also can bring various societal benefits. Indeed it will stimulate innovation, attract in-ward investment, create high-value jobs, reduce imports and open up new export markets, save lives, increase productivity, improve the environment, reduce inequality, encourage social cohesion in rural communities and enhance the standard of living for many South Africans. This paper gives an overview of SBAS-Africa describing the system architecture and developments that have taken place that, through a combination of commercial off the shelf GNSS and satcom components and the ingenuity of the consortium members, has led to a live cost-effective operational system within one year. The paper then assesses the performances and immediate benefits across different market sectors. Trials were run throughout South Africa across these sectors, including flight tests in Johannesburg and Pretoria, precise agriculture trials in Stellenbosch, UAVs in the Western Cape and Potchefstroom and maritime in Cape Town. Performances of the trials are assessed in terms of the achieved accuracy, continuity, integrity and availability.