America built a space fence to detect space junk, small satellites

Military technology often takes too much development time to have obsolete devices immediately upon launch. However, this is not true for the US Air Force Space Fence . It is a new radar system designed to track activity in Earth orbit.

Later this year, the US Air Force plans to have an electronically controlled phase array radar system located at Kwajalein atoll in the Pacific Ocean. Producer Lockheed Martin said it is a solution to urgent problems in space and civilian flights. Issues include an increase in space junk, militarization in orbit and small sizes of satellites.

Fence This space will detect objects in orbit, future orbital forecasts and collisions. The system can also detect changes compared to scheduled schedules and notify administrators. With that warning, a satellite can deal with space junk and determine the impact if there is a collision.

It can also be an important "tracking station" when there is a space war.

What is Space Fence?

Despite this name, the Space Fence does not block or block anything. Instead, the ground station will launch a radar energy network into space to track spacecraft and debris. With full warning information, spacecraft can use propulsion to avoid colliding with space junk.

This is not the first system of the United States Air Force. This unit stopped the Space Monitoring Radar (Space Surveillance Radar) in 2013. It was an outdated system that the Pentagon decided to cut down during the confiscation of the budget. Five months after the old system stopped operating, the US Air Force announced an alternative: A $ 914 million "regional watch" for satellites in Kwajalein, the same alternative. is to build a second Space Fence in Australia.

Lockheed Martin won the contract and promised a system of " revolutionizing spatial situational awareness" and found objects of size from marbles in low-earth orbit. The old space surveillance radar can track 2,000 pieces of space debris, but the New Space Barrier's radar radar is expected to detect 5-10 times the old system.

Part of the improvement of the new system is due to the semiconductor made of Gallium Nitride (GaN) , which can operate at higher voltages, radio frequency energy density is larger and smaller in size than Gallium arsenide (GaAS).

"My colleague in the United States Air Force has a good saying: We used to search by flashlight, but the Space Fence lit the attic," Bruce Schafhauser, Program Manager for the Space Fence. shared by Lockheed.

The high power of GaN semiconductors allows the system to track objects in low-earth orbit (100 miles to 1,200 miles) while increasing beams to a farther target in geostationary orbit (22,000 miles). The system can also adjust beams to create "small fences" and collect more detailed information.

Advances in "digital beamforming technology" allow the Space Fence to track objects in low-earth orbit, including part of geostationary orbit and still have strong beams to track unexpected object. (Beamforming is a technology that focuses the signal and directs it directly to the specific target instead of spreading the wifi signal in a large area).

Track satellite traffic

The ability to track large traffic and many small objects is appropriate and timely when the US small satellite market begins to grow.

Like all electronic devices, the size of satellites is getting smaller and smaller. This creates a completely new space economy - not to mention the great benefits for companies that create them. However, many small satellites in orbit have raised concerns about collisions as well as garbage. Any impact can cause a chain reaction to collisions - a nightmare for any space operator.

Regulations also limit the number of satellite registrations, especially in the United States. Along with satellite traffic monitoring tools, a good Space Fence will make administration easier.

Space Fence System at Kwajalein.

Because Kwajalein is very close to the equator, the radar screen is expected to be in the proper position to catch air traffic. Schafhauser said: "Most satellites in low Earth orbit pass through the Space Fence several times a day. We can also see a part of GEO not well covered."

However, building a large, energy-intensive facility outside the Pacific is not simple. The facility consists of two large buildings, each held under reverse pressure and covered by a Kevlar dome that allows radar waves to pass through. Millions of kilograms of structural and concrete steel are transported by plane and boat. This facility has its own 10 Megawatt (MW) power plant.

Schafhauser said: "Logistics is very difficult."

Space War Precautions

Illustration of a railgun (a new weapon) of the United States.

The prevention of tiny satellites and space junk is just one factor. Some anti-satellite weapons themselves are satellites, sent to monitor, cover other satellites or disable space communication and reconnaissance devices.

This threat is not new and some experts say it is increasing. For example, Russia has a long history of manufacturing spacecraft that can go into orbit and move on target. These cases are called "access activities" and are the first step for an attack, laser shooting or target capture. Or simply, that satellite may collide with the target.

Like most countries, US anti-satellite weapons are mostly ground-based missiles. However, the USAF also operates unmanned space aircraft with payloads depending on the task that can monitor and cause interference.

Last week, the Center for Strategic and International Studies (CSIS) released a Space Risk Report which is certain of Russia's activity: " Some times this country has manipulated space objects. In LEO and GEO, these objects were originally identified (incorrectly) as debris in the US Space Track list, which then appeared to control and conduct operations. approach".

Conclude?

"Russia's current activities indicate that they are working to restore the development of isotope space technology and counter-space."

This is the kind of risk that Space Fence can cope with. To win in any encounter, even in orbit, it is necessary to know where the opponent is. In Lockheed's introductory video, the radar tracks a satellite when it changes its position or even redirects - factors that can predict an attack.

When asked, Schafhauser acknowledged this, especially predictions in the geostationary orbital area - where national security satellites operate. However, he refused to answer detailed questions regarding military purposes.

The Space Fence seems to be going in the right direction, but the Joint Space Operations Center is not ready. Control and control system uses "serious errors" data and does not guarantee security, according to the Pentagon's annual performance review report.

The report contains another interesting detail, which is the description of another spatial fence covering Iran."Iran has also developed its spatial potential with military applications, such as the space monitoring center announced in June 2013, using radar, photovoltaic and radio monitoring " , reports. fox pointed out. According to Iranian Defense Minister Ahmad Vahidi, the base aims to ensure the security of national space facilities and to monitor space objects, especially high-altitude satellites.

Russia also has a large space monitoring network and China is also rapidly improving its space potential.

Schafhauser said the US fence had its first orbit observations, called the "first track" (in radar slang). Accordingly, the percentage of arrays they can use during testing is increasing and the key for this facility will be transferred to the US Air Force later this year.

In the 20th century, the walls and checkpoints outlined the potential conflict boundaries. The 21st century can be said to be similar to energy barriers on space.

"We can divide the sky with energy , " Schafhauser said.