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Direct-to-Mobile Communications Using LEO Satellites gets a Step Closer

In Nov 2022, Rakuten Mobile announced that it has obtained preliminary experimental test station licenses to conduct mobile communication tests and preliminary verification in Japan using AST SpaceMobile’s low earth orbit satellite, BlueWalker 3.

We blogged about AST & Science's ambition to have SpaceMobile beam 4G/5G directly to devices here and here. Back in Nov. AST SpaceMobile announced that it had successfully completed deployment of the communications array for its test satellite, BlueWalker 3 (“BW3”), in orbit. I found the Tweet showing the unfolding very interesting.

Coming back to Rakuten Mobile's announcement, the press release said:

In order to conduct preliminary verification and communication tests between the test satellite launched by AST SpaceMobile, a gateway earth station in Japan and smartphones on earth, Rakuten Mobile made applications to the Tohoku Telecommunications Bureau for a Gateway Experimental Test Station license and to the Kanto Telecommunications Bureau for a Mobile Terminal Experimental Test Station license, and both applications have now been approved.

Upon receiving the licenses, Rakuten Mobile will begin to prepare a gateway earth station in Fukushima Prefecture to test and verify direct communication between BlueWalker 3 and mobile devices in mountainous areas in Hokkaido.

To enable testing with Rakuten Mobile and other carriers, Rakuten Symphony will provide a variety of software from its Symworld™ product portfolio to AST SpaceMobile to be integrated into the company’s satellite system and enable the company’s space-based cellular broadband network. The software to be integrated includes Rakuten Symphony’s vRAN (virtualized Radio Access Network) software, OSS (Operations Support Systems) and BSS (Business Support Systems) software.

Rakuten Mobile will continue its efforts to expand Rakuten's coverage area and improve communication quality so that customers can enjoy comfortable and convenient communication services anywhere.

A recent article in IEEE Spectrum also examines how existing smartphones will connect with new satellite constellations in 2023.

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