December 4, 2017 - China Launches Communication Satellite

On December 4, 2017, you're actually looking at a redesignation milestone rather than a new launch. China's Shijian-13 — launched April 12, 2017 — officially became Zhongxing-16 after completing on-orbit testing. It was China's first true high-throughput satellite, delivering over 20 Gbps of capacity through 26 Ka-band spot beams and making history as the first satellite to demonstrate space-to-ground laser communications from GEO. There's much more to this satellite's groundbreaking story.

Key Takeaways

• China launched the Zhongxing-16 (ChinaSat-16) communications satellite on April 12, 2017, from Xichang Satellite Launch Center aboard a Long March-3B rocket.
• The satellite became China's first to use electric propulsion (four LIPS-200 ion engines) for long-term geostationary station-keeping.
• Zhongxing-16 achieved over 20 Gbps total throughput via a Ka-band system with 26 user spot beams.
• It established China's first space-to-ground laser communication link from geostationary orbit, demonstrating 150 Mbps downloads.
• Built on the DFH-3B/DFH-4S platform, the satellite influenced six additional Chinese communications satellites developed in 2017.

Shijian-13: The Chinese Satellite That Changed Broadband From Space

On April 12, 2017, China launched Shijian-13 from the Xichang Satellite Launch Center in Sichuan Province aboard a Long March-3B rocket, sending the 4,600 kg satellite into geostationary orbit at 110.5° East. You can think of this mission as China's declaration of satellite sovereignty — it used domestically built components to close a critical technology gap in space-based broadband.

The satellite's 26 Ka-band user beams deliver over 20 Gbps of capacity, supporting 150 Mbps downloads across China's mainland and offshore areas. That reach extends rural connectivity significantly, enabling distance learning, telemedicine, and emergency communications in underserved regions.

It also introduced China's first electric propulsion system using four LIPS-200 ion engines, and integrated a space-to-ground laser communications terminal — marking the start of China's satellite internet era. The satellite was designed and manufactured by China Academy of Space Technology, drawing on the DFH-3B satellite bus as its foundational platform. Following successful technical tests conducted in orbit, the satellite received its operational designation as Zhongxing-16, reflecting China's standard process of confirming performance before formally commissioning a new spacecraft. This approach to achieving high-value results through targeted innovation echoes NASA's Faster, Better, Cheaper philosophy, which demonstrated that cost-conscious engineering decisions could still deliver significant scientific and technological returns.

Why Shijian-13 Was China's First True High-Throughput Satellite

What made Shijian-13 more than just another communications satellite was its capacity to do something no Chinese satellite had done before: deliver over 20 Gbps of throughput — exceeding the combined output of every previous Chinese communications satellite. Its Ka-band system and spot beam technology enabled frequency reuse, pushing bandwidth directly to end users across China and the Asia-Pacific. You can't achieve that scale without deliberate spectrum policy decisions that prioritize high-efficiency frequency allocation.

The 220-kilogram HTS payload also redefined what domestic engineering could produce without foreign components. With 26 user beams covering remote regions and maritime corridors, Shijian-13 addressed real service gaps. Satellite security considerations shaped how those beams were structured, ensuring reliable communications for emergency response and critical infrastructure across underserved territories. The spacecraft was built on a DFH-4S bus, marking one of the first applications of that platform to also test electric propulsion systems in geostationary orbit.

Shijian-13 was launched aboard a Long March 3B rocket from the Xichang space center in Sichuan province, China, placing the satellite into a geostationary transfer orbit with an apogee near 35,800 kilometers. Following orbit-raising using its conventional liquid-fueled thruster, the satellite became the first Chinese spacecraft to rely on electric thrusters for long-term station-keeping at geostationary orbit. An on-board laser link terminal was also carried to conduct experimental laser communications technology testing in orbit.

Shijian-13's Electric Propulsion and Ka-Band Technology

Launched on April 12, 2017, Shijian-13 carried two technologies that set it apart from any Chinese satellite before it: electric propulsion and a Ka-band multi-beam broadband system. Its four LIPS-200 ion engines deliver a specific impulse more than ten times that of conventional chemical propellants, drastically cutting propellant mass and freeing up payload capacity. A liquid-fueled thruster handles initial orbit circularization, while the electric propulsion system takes over for station-keeping.

On the communications side, Ka band beamforming powers 26 user beams across China and offshore areas, pushing total capacity beyond 20 Gbps. You're looking at a system that supports airborne, maritime, and emergency communications, enabling seamless "Communication on the Move" for vehicles, ships, and aircraft operating across the Asia-Pacific region. The satellite also carries experimental laser communication hardware designed to test space-to-ground optical links as part of its broader mission objectives.

Shijian-13's Real-World Speeds: 150 Mbps Downloads From Space

Beyond the hardware specs and beam counts, Shijian-13's laser communication system delivered something tangible: a 150 Mbps download speed from geostationary orbit to a ground station, marking China's first successful space-to-ground laser link. That speed outperforms most home broadband connections you'd find today, and it came from a satellite sitting roughly 36,000 kilometers above Earth.

Engineers confirmed laser reliability through operational tests, validating beam alignment precision between the satellite's laser terminal and Earth stations below. The system demonstrated router-like functionality in space, enabling real-time multimedia relay, emergency data transfer, and support for distance learning and remote medicine. Combined with Shijian-13's 20 Gbps Ka-band capacity, this laser achievement set a clear foundation for China's next generation of high-speed space-based broadband networks. Airlines and rural underserved areas stand to benefit most directly, as the satellite's coverage footprint extends Internet access to regions where traditional cable infrastructure remains out of reach.

Shijian-13's Impact on Aviation, Maritime, and Rail Internet

Across aviation, maritime, and rail sectors, Shijian-13 delivers practical, high-speed connectivity where traditional ground-based infrastructure simply can't reach.

If you're flying, the Ka-band broadband system enables seamless beam switching, supporting "Communication on the Move" while protecting passenger privacy through dedicated airborne terminals.

At sea, 26 user beams cover offshore areas, letting vessels maintain reliable broadband, handle emergency communications, and simplify antenna maintenance with automatic tracking systems.

On high-speed trains like China's CRH network, you can download a 1-gigabit film in under one minute, with multi-beam technology sustaining stable access for 300,000 simultaneous users despite challenging terrain.

In each environment, Shijian-13's 20 Gbps capacity ensures you're never dependent on ground-based limitations, making consistent, high-quality Internet a real possibility across all three mobile platforms. Powering these capabilities is an electric propulsion system that replaces traditional chemical fuel, resulting in a lighter satellite design and a longer 15-year service life.

Beyond these mobile platforms, Shijian-13 also plays a critical role in disaster response, where its first laser communications system on a Chinese high-orbit long-life satellite enables those at natural disaster scenes to report on emergencies with greater speed and reliability. This capability mirrors the foundational goals behind early networked communication, as ARPANET's original design prioritized survivable data transmission precisely so critical information could reach its destination even when conventional infrastructure was compromised.

How Shijian-13 Shaped the Next Generation of Chinese Communication Satellites

Shijian-13's legacy extends well beyond its operational lifespan, reshaping how China designs, builds, and deploys communication satellites. Its 20 Gbps throughput benchmark raised capacity standards across the entire Chinese fleet, pushing engineers to develop more powerful successors. You can trace its electric propulsion success directly into follow-on models, while its laser communications experiments accelerated optical system development for future missions.

The DFH-3B bus enhancements it validated influenced six additional communications satellites developed in 2017 alone. In satellite manufacturing, domestic component integration became a stronger priority, reducing external dependencies. Its Ka-band deployment model also refined ground segment integration strategies, improving how operators connect orbital assets to terrestrial broadband infrastructure. Shijian-13 didn't just perform—it established the technical and operational blueprint China's next generation of satellites continues building upon. This kind of leap in data transmission capability mirrors the early ambitions of terrestrial networking, where AT&T's Bell 101 first demonstrated that phone-line data transmission was viable for commercial and government-scale operations in 1959.