Lockheed Martin [LMT] has delivered the latest advanced extremely high frequency military communications satellite to Cape Canaveral Air Force Station, Florida, the company said Aug. 6.

The system is the fourth of six nuclear-hardened, jam-resistant protected communications satellites planned for the Air Force. It is scheduled to be launched into orbit this October aboard an Atlas V rocket, according to Lockheed Martin.

The delivery of this satellite in orbit will connect all four of the currently operational satellites, “forming a geostationary ring to provide uninterrupted global communications,” said Michael Cacheiro, company vice president of protected communications, in a press release. The system also serves international partners, including the Netherlands and the United Kingdom.

Nearly $30 million is authorized in the fiscal year 2019 National Defense Authorization Act (NDAA) for advanced-EHF procurement, which will fund the fifth and sixth satellites along with technical support.

The NDAA, which cleared both the Senate and the House, also authorizes over $151 million in research, development, technology and evaluation funds, including about $83 million for terminal development and about $29.4 million for the Air Force’s next-generation protected communications program.

Three advanced-EHF satellites have been launched since 2010, according to the Air Force. Once the constellation is complete, the program is expected to provide 10 times the throughput of the service’s 1990s-era Milstar platforms.