appConfigEntityId

bodyType

customContents

entityId

entityUuid

isVideo

articlePageQuery

article

articleSchemaContent

content

hooksArticlePageAdvertisementConfigArticle

hooksArticlePageFloatingButtonConfigArticle

appConfig

filter

json

liveArticle

Chao Kong

A satellite that can provide 24/7 surveillance of a third of the Earth’s surface relies on a rare mineral whose global supply is dominated by China, a new study has disclosed.
The Ludi Tance-4 01 radar satellite, powered by gallium nitride (GaN) semiconductors, is the only satellite of its kind.
It orbits 36,000km (22,000 miles) above the Earth and is able to stay in what is known as a geosynchronous orbit, which keeps it fixed over the same spot.
This allows it to monitor both large areas of the planet and moving targets – something the United States has spent decades trying to achieve without success.
China has near-total dominance of the global supply of GaN – a key component in active electronically scanned array radars, electronic warfare systems and next-generation defence platforms – and has restricted gallium exports since the satellite launched in August 2023.


The metal is mainly extracted as a by-product of alumina production rather than mined independently and China, the world’s largest aluminium producer, accounts for more than 95 per cent of global primary gallium production.
The satellite uses GaN technology to power its solid-state amplifiers, the devices that send electromagnetic waves to its synthetic-aperture radar, according to the paper, which was written by researchers at the Xian Institute of Space Radio Technology and published in the Journal of Microwaves.
Its development was supported by funding from the National Key Laboratory of Space Microwave Communication.
Because the satellite operates so far from Earth, it needs stronger microwave transmission power than low-orbit systems to generate the 2D and 3D images created by the synthetic-aperture radar.
High power levels are also needed to improve accuracy when identifying targets and to protect the satellite’s systems from interference.
To tackle the problem, scientists developed a solid-state power amplifier that uses GaN high-electron-mobility transistors. Each one can generate 800 watts and, when combined in the satellite, they produce more than 18,000 watts.
The study monitored how 20 of these amplifiers performed over two years in orbit and concluded that they “met the requirements of an eight-year service life, high performance and high reliability”.

The paper reported that the device had also reached a power-added efficiency of 50.3 per cent.
China has been steadily tightening its restrictions on gallium exports since the satellite was launched.
In late 2024, it effectively blocked exports of gallium-related products to the US. These restrictions were paused late last year – until November 27 this year – but the ban on military‑end use exports remains in force, according to the Ministry of Commerce.


China tested a handheld submarine detector. It tracked a subway train underground

How Wang Zhenyi, Chinese female astronomer and mathematician, defied gender expectations

Chinese drug loberamisal extends stroke treatment window from 6 hours to 2 days

China-Russia space camp in Malaysia opens to youth in Southeast Asia

Science

China’s unique high-orbit satellite is using a rare metal the US struggles to obtain

The satellite can monitor a third of the Earth’s surface. Photo: China Academy of Space Technology 

Each high-power amplifier can generate 800 watts. Photo: Journal of Microwaves

China unveils high-power microwave weapon arsenal with up to 100 gigawatts of power

China displays a high-power microwave weapon system during the Victory Day parade in Beijing on September 3, 2025. Photo: Xinhua

China’s rare earth industry has critical weakness, researchers warn

A mine in Baotou, Inner Mongolia, a part of China’s vast rare earth mining industry. But new study says the country’s “international patent layout remains insufficient”. Photo: AP

A wheel loader moves ore at a rare earth mine in Mountain Pass, California – one of the few significant rare earth production sites outside China. Photo: Reuters

Rare earth polishing materials, a key component in semiconductor and precision manufacturing, on display in March at the National Museum of China. Photo: Reuters

Neodymium-iron-boron magnetic powder and rare earth permanent magnet materials are displayed at a March exhibition on China’s manufacturing achievements, at the National Museum in Beijing. Photo: Reuters

News

China

Beijing dominates the global supply of gallium nitride – which has been revealed as a key component in its Ludi Tance-4 01 satellite


Beijing dominates the global supply of gallium nitride – which has been revealed as a key component in its Ludi Tance-4 01 satellite.


United States

China’s unique high-orbit satellite is using a rare metal the US struggles to obtain

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}Beijing dominates the global supply of gallium nitride – which has been revealed as a key component in its Ludi Tance-4 01 satellite

Beijing dominates the global supply of gallium nitride – which has been revealed as a key component in its Ludi Tance-4 01 satellite