Geostationary Defense and Strategic Communications Satellite (SGDC) is a dual-use telecommunications satellite used by the Brazilian Government and armed forces. SGDC was launched from the Guiana Space Centre near Kourou, French Guiana in May 2017.
The satellite provides secure strategic defence communications for the Brazilian Ministry of Defence and broadband services for the Ministry of Telecommunications through the National Broadband Plan (PNBL).
Positioned in geostationary orbit at an angle of 75° west, the satellite is operated by Visiona Tecnologia Espacial, a joint venture between Embraer Defense & Security and Telebras Telecomunicaçoes Brasileiras.
The Brazilian Space Agency signed a memorandum of understanding (MoU) with Thales Alenia Space in 2013 for a technology transfer plan to support Brazil in its efforts to develop its own space programme.
SGDC programme details
Visiona Tecnologia Espacial signed a R$1.3bn ($570m) contract with Telebras for the SGDC satellite programme in November 2013.
In December 2013, Thales Alenia Space appointed Visiona Tecnologia Espacial as the prime contractor to build the SGDC satellite and ground segment, as well as oversee orbital positioning and in-orbit tests (IOT).
As part of the contractual agreement, Thales Alenia Space also provided complete training and operational support for Brazilian operators in coordination with the Brazilian Space Agency (AEB). The programme also involves national space research institute INPE and the Brazilian Ministry of Defence.
The SGDC’s design was reviewed by the Brazilian Air Force (FAB) in Toulouse, France, and received approval for manufacturing in January 2015. Upon completion of construction, the satellite was shipped in February 2017.
Design and features of the geostationary military communication satellite
Based on the HTS Spacebus 4000-C3 platform, the SGDC satellite is designed for a life of 15 years. It had a weight of approximately 5,800kg at launch and a payload power of more than 11kW.
SGDC also reduces the digital divide in Brazil by providing high-quality Internet services.
Payloads carried on the SGDC satellite
The satellite is fitted with seven X-band military payload and 50 efficient Ka-band payload transponders offering a throughput of 80Gbps. It is also equipped with aluminium battery support panel.
The five X-band transponders cover all of South America and neighbouring maritime routes. The Ka-band payload offers government strategic data communications and expands broadband services to remote areas in Brazil.
The ground segment consists of nominal and redundant satellite and mission control centres. It is used to perform tests and control the SGDC satellite and payloads.
In December 2013, Arianespace signed a launch contract with Visiona Tecnologia Espacial for the SGDC satellite aboard Ariane 5 heavy-lift launcher from the Guiana Space Centre near Kourou, French Guiana.
The Ariane 5 launch vehicle has a length of 50.5m and a typical launch weight of 780t. It has a payload capacity of 20,000kg to low-Earth orbit (LEO) and 10,000kg to geostationary transfer orbit (GTO).
The main cryogenic stage is powered by a Vulcain main engine, which burns liquid hydrogen. It is fitted with two solid boosters to develop 90% thrust.
Communications & Power Industries (CPI) Satcom Division was selected in September 2014 to provide 500W continuous wave (CW) Ka-band Traveling Wave Tube Amplifiers (TWTAs) for use in critical telemetry, tracking and control.
Systems Tool Kit (STK) software, developed by Analytical Graphics (AGI), is used by Visiona Technology Espacial to analyse and evaluate the SGDC satellite orbit, communication links and communications coverage.