Introduction

Smartphone Direct Connection to Satellite technology is a huge innovative breakthrough in global mobile satellite communication, which is the leading technology in the future 6G and serves as the crucial and fundamental technology for the integrated development of space-ground industry chain.

Breaking through the difficulties of ultra-long distance communication with GEO satellite and building the world's first state-of-the-art space-ground integrated mobile communication network

China Telecom along with industry partners bridged the huge technical gap of mobile phones' direct communication with GEO satellite. It newly released the communication system "space-ground integrated direct phone connection to satellite" and made holistic innovation on 5 large areas including direct phone connection to satellite communication standard, space-ground integrated communication network, direct phone connection to satellite flagship products, space-ground integrated operation framework, and end-to-end industrial testing and validation system, thereby achieving smartphone direct connection to Tiantong GEO satellite with "no change in SIM cards or phone numbers". This project announced the global debut of smartphone direct connection to satellite for audio and bi-directional SMS commercial service. In addition, it established world's first state-of-the-art space-ground integrated mobile communication network, where direct phone connection to satellite communication technology as well as terminal products take the lead internationally and fill the blank of the industry.

By May 2025, the number of smartphones with direct connection to Tiantong Satellite capability announced by major phone brands such as Huawei, Honor, Xiaomi, OPPO, vivo, ZTE, Samsung, etc. has reached 41, along with a terminal shipment of more than 25 million, which produced a sales income more than 100 billion. China Telecom direct phone connection to satellite service has accumulated to 5.168 million subscribers with a 425 million Chinese yuan accumulated income.

Through critical technology innovation of direct phone connection to satellite, China Telecom has announced direct phone connection to satellite service in Hong Kong on May 8, 2024 and in Laos in May 2025, respectively. This promoted the international operation of China's satellite system, thereby providing the bridge for high-quality interconnection between domestic and overseas infrastructures.

Leading the innovation of direct satellite technology and building a new mode of satellite industry development

In leading innovation of technology, this project has formed a series of direct phone connection intellectual property system via holistic innovation in 5 areas including communication standards, network structure, flagship products, operation framework and testing system. It authorized 101 invention patents, 40 registered software copyrights and 16 published papers. In comparison to other service operators in the world which can only provide satellite SOS SMS functionality, this project has successfully provided a holistic solution to enterprises for direct phone connection to satellite worldwide.

In promoting industry development, this project utilized the advantage of scale in terrestrial mobile communication industry to integrate ground with space to drive the mass production and reduction in cost of satellite terminals with technology innovation. It strongly advanced the integration of space-ground integrated industry and reduced costs while enhancing efficiency in satellite applications. This drives the low-cost, large-scale production of direct-to-satellite terminals and chips. Compared with the annual sales volume of 60,000 to 70,000 in the Tiantong industrial terminal market, direct phone connection to satellite is expected to boost industry growth by several hundred times. It is estimated that by 2025, sales of terminals supporting direct phone connection to satellite functionality will exceed 30 million—nearly 10% of China's annual mobile phone output—expanding from the mid-to-high-end segment to entry-level smartphones priced around 1000 Chinese yuan.