Rakuten Mobile and AST SpaceMobile Make History in Space-Based Cellular Connectivity, Completing the First Ever Space-Based Voice Call Using Everyday Unmodified Smartphones

- The groundbreaking milestone was reached with support from partners including Rakuten, Vodafone and AT&T, opening opportunities for global 2G, 3G, 4G LTE and 5G cellular broadband access -

AST SpaceMobile staff at the company’s Midland, Texas headquarters, with engineers from testing partners Rakuten, Vodafone and AT&T

MIDLAND, TX, and Tokyo, Japan, April 26, 2023 – Rakuten Mobile, Inc. ("Rakuten Mobile") and AST SpaceMobile, Inc. (“AST SpaceMobile”) (NASDAQ: ASTS), the company building the first and only space-based cellular broadband network accessible directly by standard mobile phones, today announced the successful completion of the first-ever two-way voice calls, directly to everyday unmodified smartphones using the BlueWalker 3 (“BW3”) satellite. The first voice call was made from the Midland, Texas area to Rakuten in Japan over AT&T spectrum at April 21, 2023 10:31am Japan standard time (Apr 20, 8:31pm CT). This is the first time anyone has ever achieved a direct voice connection from space to everyday cellular devices, demonstrating a significant advancement in AST SpaceMobile's mission to provide broadband services to the nearly 50% of the global population who remain unconnected.

The initial test calls have validated the AST SpaceMobile patented system and architecture, and were completed using unmodified smartphones. The calls demonstrated the power of AST SpaceMobile’s BW3 satellite, the largest-ever commercial communications array deployed in low Earth orbit and is an important step to providing space-based 2G, 3G, 4G LTE and 5G cellular broadband globally. Engineers from Rakuten, Vodafone and AT&T participated in the preparation and testing of the first voice calls with BW3.

"Achieving what many once considered impossible, we have reached the most significant milestone to date in our quest to deliver global cellular broadband from space. While we take a moment to celebrate this tremendous accomplishment, we remain focused on the path ahead and pivotal next steps that get us closer to our goal of transforming the way the world connects," said Abel Avellan, Chairman and Chief Executive Officer of AST SpaceMobile. “I am immensely proud of our team and our incredible partners, whose unwavering dedication and tireless efforts have brought us to this pivotal moment."

Mickey Mikitani, Rakuten Chairman & CEO, commented: “It was a unique thrill and honor to have the Rakuten team talk with Abel in a world-first direct-to-satellite experience. Congratulations to AST SpaceMobile and all of its strategic collaborators on this groundbreaking event. As technological advancements like space connectivity become possible with pioneers like AST SpaceMobile, Rakuten will also progress even further along the road to democratizing connectivity for all.”


AST SpaceMobile’s BlueWalker 3 test satellite currently in low Earth orbit


Chairman & CEO Abel Avellan and an AST SpaceMobile engineer completing test calls in Texas


AST SpaceMobile engineers who supported the first voice calls over BlueWalker 3 outside company headquarters in Midland, Texas

In addition to test calls, AST SpaceMobile engineers conducted initial compatibility tests on a variety of smartphones and devices. The phones successfully exchanged Subscriber Identification Module (“SIM”) and network information directly to BW3 -- crucial for delivering broadband connectivity from space to any phone or device. Additional testing and measurements on the smartphone uplink and downlink signal strength confirm the ability to support cellular broadband speeds and and 4G LTE / 5G waveforms.

In March 2020, Rakuten Group and AST SpaceMobile announced a strategic partnership which is aimed at developing the technology to deliver a space-based mobile service using low earth orbit satellites and Rakuten Mobile spectrum in Japan. The joint project’s vision for the service is to offer voice calls and web browsing in addition to text messaging on unmodified standard smartphones. The service is intended to offer coverage to areas in which it is difficult to provide connectivity with traditional technology, including mountainous regions and islands. It would also support connectivity in areas struck by the natural disasters commonly experienced in Japan.

AST SpaceMobile has over 2,600 patent and patent-pending claims for its technology and built state-of-the-art facilities in Midland, Texas that collectively span 185,000 square feet. AST SpaceMobile has agreements and understandings with mobile network operators globally that have approximately 2 billion existing subscribers, including Vodafone Group, Rakuten Mobile, AT&T, Bell Canada, Orange, Telefonica, TIM, Saudi Telecom Company, Zain KSA, Etisalat, Indosat Ooredoo Hutchison, Smart Communications, Globe Telecom, Millicom, Smartfren, Telecom Argentina, Telstra, Africell, Liberty Latin America and others.

Rakuten Mobile, Inc. ("Rakuten Mobile") obtained preliminary experimental test station licenses in November 2022, to conduct mobile communication tests and preliminary verification in Japan using AST SpaceMobile’s low earth orbit satellite, BlueWalker 3. Subject to grant of testing licences, Rakuten Mobile is preparing for further trials to be conducted within Japan.

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.


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