Australian Radar Researchers Seek New Design Wrinkles

Australian Radar Researchers Seek New Design Wrinkles
By David A. Fulghum, Aviation Week & Space Technology
06/01/2006

ADELAIDE, Australia - Slashing power use, eliminating clutter, gleaning more information from targets and convincing radars that they are something else - in size, shape and mission - are long-terms goals for Australian radar researchers.

A key facility for developing future capabilities is the Defense Science and Technology Organization's Edinburgh-based microwave radar center of excellence. At the heart of DSTO's effort is the Australian Defense Force's choice of the Active Electronically Scanned Array (AESA) radar on its new Wedgetail airborne early warning and control aircraft and the F-35 Joint Strike Fighter, a future purchase.

AESA is considered a war-changing leap in technology by planners in Australia, Britain and the U.S., which are fielding various versions of the advanced radar. In addition to being very precise, the radar's images are digitized so they can be fed quickly into a global information grid for immediate use by warfighters and intelligence organizations.

Andrew Shaw, research leader of the microwave radar advanced concepts effort, points out some of Austalia's areas of interest. Others are veiled by classification.

"We're looking at element-level digitization for both transmit and receive" functions at the face of the antenna to reduce energy demands, Shaw says. Other thrusts include improved detection of small objects, generation of virtual antennas for specialized applications, as well as a combined effort to eliminate clutter and improve the ability to find new targets. They also want to improve management of time and energy so that the radar can focus its power on areas where it is hardest to find targets.

The distributed array - made up of hundreds, sometimes thousands of relatively tiny transmitter/receiver elements - can be used as a sensor to detect very small, even stealthy targets, or as a weapon when all its transmitters are focused on a single spot. It also can function as a communications device capable of moving huge video files around the battlefield in real-time. With the proper software modifications, the radar is capable of electronic attack through jamming enemy electronics or invading their communications networks with algorithm packages designed to mine information.

Since the Royal Australian Air Force (RAAF) is already fielding AESA radars, DSTO wants to explore the new technology's potential. What's not clear yet is how much access the RAAF will have to the radar's secrets. For example, the United Arab Emirate's new block 60 F-16C/D's have an AESA radar with extended range and small target detection capabilities available in several modes for ground and sea targets. But, "it is a locked box and the U.S. has all the keys," says a long-time Pentagon radar specialist.

The Australian's fourth generation AESA will have even more power and small target detection capability. As a result, "the Australians would like to stay up with the technology and make improvements where it makes sense," the U.S. specialist says. "It will have quite a bit of electronic surveillance and intelligence collection capability. It won't be designed for electronic attack - that would take a special variant - but it could be used as a Wild Weasel" for attacking air defense radars. Australia's access will be the result of ongoing negotiations about U.S. export laws. What most countries can't duplicate is the hundreds of millions of dollars that the U.S. has spent on AESA transmitter/receiver technology, but they could afford to refine the product, he says.

Shaw agrees that DSTO is not trying to invent anything new. But it doesn't need to.

"What I can do now with advanced computering power was just not possible before," he says. "I'm exploiting what I couldn't afford to do before. What has become most important is how much information can I get down the pipe [from the AESA array] and plug into the front of the computer. Once I can get 10 gigabits per second down a piece of wire, I don't have to throw away so much information. There is so much commercial off-the-shelf computing power to move large quantities of data around that it has made a larger contribution to modern radar systems than the AESA itself. The main thing is that it allows AESA to do is space-time adaptive processing. If I have a noise or clutter source in a particular direction, it is a method of automatically removing it very precisely. Radar is all about clutter."

One exotic concept the Australians are interested in is multiple input, multiple output (MIMO). It's been used for communications, but DSTO wants to apply it to radar.

"The idea is that you transmit a set of waveforms from the aperture. Each element transmits a different one," Shaw says. "You receive all the waveforms on all the antenna elements. That suggests that you can improve the probability of detection [since a target may respond to one wave form, but not another] and you can generate a virtual antenna with characteristics far different from the actual antenna."

"I can make my antenna look bigger in a mathematical sense. But instead of using space and time, to extract data as I fly along, I'm using frequency or waveform space. It gives me a virtual antenna that is very much bigger and changes its shape. That means changing all the RF characteristics including the generation of sidelobes where the energy peaks are.

"It also has interesting properties in that the waveform return looks different in each direction you point the radar. A signal pointed at one position looks like one thing and pointed somewhere else looks like something different. As long as I know what signal I'm sending in time and space, if you try to repeat something back to me [such as spoofing] to confuse my radar, I know it's you. [Since radar antennas are openings into networks,] anytime you can determine that someone is fiddling with your signals, it's very useful."

Despite identification of AESA as a war-changing military device, Shaw points out that it is not a perfect design. Much of the team's focus will be on "how we exploit the advantages rather than the compromises" with the underlying expectation that the effort "won't come to any sort of system fruition for 10 years at least," he says.

Pukin' Dog has said all along that the F-35 will be canceled, but with so many international partners already kicking in cash for development, I think it's inevitable.

All they will do is chop back numbers...and then the unit-costs automatically sky-rocket...and 'oila...the international partners back out too, and...get really mad that they were burned by this Administration. That's the problem with the Administration. Ever since it came in, it seems to have had some confabulatory idea that it could just, as did Xlinton, continue the defense holiday. In the 2000 campaign they had promised an immediate increase in the defense budget to cure armament maintenance, service, training and supply issues...and looming shortfalls in the navy, air force and marines ship and plane inventories. Congress had actually managed to push through a modest $15 billion increase in December before Bush took office. And when he did, instead of the emergency relief expected...and needed, he simply stalled and asked the services...in effect... what they needed to cure the damage done by Xlinton. Apparently the bill..an additional $95 billion... was so high that it was laughed out of the OMB...and they were told that they could live on peanuts...the White House then stalled the routine budget increases an inexcusable 4 months past the traditional mid-year budget approval, and then they added amounts barely equal to inflationary increases...yet these were announced with misleading fanfare and euphemisms as if he had honored his promises. Robert Kagan, one of the solid defense conservatives properly observed in 20001, before 9-11:

Indefensible Defense Budget
By Robert Kagan
Washington Post, July 20, 2001, Pg. 31
Excerpts
...
Bush's proposed defense budget of $329 billion puts defense spending at 3 percent. As Republicans liked to point out during the Clinton years, it hasn't been that low since Pearl Harbor.
...
Jimmy Carter's defense secretary, Harold Brown, and former defense secretary James Schlesinger have argued in these pages for an increase of at least $50 billion a year, and former Clinton Pentagon officials agree. The Army, Navy, Air Force and Marines say they need $32 billion this year just to keep planes flying, tanks rolling and troops training. Never mind buying new weapons systems to replace those that are now a quarter-century old. As one Pentagon official put it, President Bush's $18 billion is barely enough "to keep us treading water." With $9 billion set aside for military housing, health and pay increases, Bush's budget gives Rumsfeld too little to repair the military's readiness problems, much less to modernize and "transform" it to fight the wars of the future.
...
Remember when Republicans were more trustworthy on defense and national security than Democrats? This Bush presidency may change all that. After years of berating Clinton, Republicans are suddenly mute -- what defense budget crisis? -- while Rumsfeld and Wolfowitz are hung out to dry.
The writer, a senior associate at the Carnegie Endowment for International Peace, writes a monthly column for The Post.

And other defense commentators have noted since that the defense expenditures...on the core infrastructure replacement (recapitalization which has been on holiday since about 1990) have only actually gotten worse.

As Loren Thompson reported last Summer:

One option [that Rumsfeld clearly is considering] would kill the Air Force's version of the F-35, eliminating about 70% of the planned domestic buy. Another option would kill both the Air Force and Navy versions. Either way, the whole program would eventually disappear, because whatever planes remained would end up looking astronomically expensive. As for the more capable F-22 Raptor -- the plane the Air Force says it really needs to maintain global air superiority for the next generation (and which has already been largely paid for) -- that would cease production by the end of the decade. Incidentally, so would every other fixed-wing aircraft the military is currently buying.
If some foreign country had visited this sort of destruction on America's military, historians would call it an huge defeat.

I think Thompson's rhetorical observation is apt.

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