posted on Sep, 23 2013 @ 07:40 AM
At any rate, to wax effulgent (I been reading my dictionary - it got that boring), there are any number of ways to defeat low observability, only most
of them are really hard to do. So you've got to weigh the likelihood of someone's claim on their innate techno-prowess.
A few examples:
1) The old use a bigger hammer technique: it's not that most stealth doesn't reflect at all, it just doesn't reflect that much, so your radar
system edits out the return as being a bug or something due to the low RCS. So what you do is, you firehose a wad of power at the sky, with a cleverly
tagged output. This is what AESA's "burn through" mode does. You count on the other guy's LO technology to actually reflect enough for AESA to
pick it up, un-bollox the return based on the tag, and carefully look at it to see if it IS a return and not a bug. Mostly, bugs are too small to
reflect well at most radar wavelengths. So you do some clever chirping and FM diddling once you see what LOOKS like a return, and if it responds to
bigger wavelengths than a bug would reflect, you mark that thing a LO craft and track it. It works, but you've got to have a way agile system to do
it, and one with a lot of processor power and CW output. AESA qualifies. AESA can defeat most anyone's LO technology within a dogfight area.
Although they don't talk about it.
2) Use a WIDE range of frequencies: the very transparent elephant in the room is the often rumored UWB non-observable radar. It's the gold standard,
if you had a craft with one on. UWBs are not yet known, really, although the basics have been around for years. Impulse UWB in a fieldable radar is
TOUGH. However, we've got one flying around, and have had for (checks watch) about three years. It's even got it's very own AN designator, and I
can tell you that because Kirtland's spiffy medical flight surgeon group blew that little project on the base newspaper. I didn't see where anyone
archived that little tidbit, I reported it the second I saw it and no I won't post the article. They were concerned about the effect of UWB emissions
on groundcrew, so they named off the project, described the system and what not. UWB smears its emissions over a theoretically infinite range of
frequencies, in practice if you can do it over about 500MHz you've done ok. The cool part is that if you do it really well, there's no one spot you
can look at it and say "Hey, there's a signal!" so you're essentially unobservable. It raises the local noise floor a fraction of a db. Since
it's blasting across the spectrum, UWB finds the places where your RAM and internal structure just don't cut it. A lot of 'stealth' technology is
only good for a certain range of frequencies, whatever the designers thought the system would have to foil. So it's not as good as UWB's range.
Generally speaking, if you HAD one, UWB could defeat most stealth as well. In addition, there are a lot of neat math tricks that come into play that
make your antenna efficiencies go through the roof and whatnot, so it doesn't have to radiate that much total power either. And it gives you some
neat time coherency tricks so you can easily find where a target is without timing things. The problem comes in that there was little
research/development in that area - you just CAN'T use stock radar equations, so it was start from scratch, more or less. And it's weird and
unintuitive, so you have to retrain everyone. But UWB does work, and work well. Especially for stock targets, but it's better than AESA at LO.
3) Multistatic radar - this is the one where you hear about tracking stealth with cell phone towers: Well, yes and no. What it does for you is detect
that something is there, mostly. Sandia has a neat trick for imaging planes that fly through the towers with a sort of reverse-SAR processing of the
data you probably haven't heard of. Russia likes multstatics. A multistatic array will always detect stealth, even the really good stealth like
plasmonic stealth. But it generally only tells you something passed the grid. It's not the sort of thing you can use for fighter direction. I suppose
if you didn't alter course and speed after going through the Sandia version you could be vectored in on, but who'd do that?
4) Looking for holes: if you're really good and have ground based systems, you can look up at the sky and look for holes in noise. If you've got a
low flying LO, they'll leave a characteristic dip in space noise you can not only spot, but you can get position, vector and speed data from. Can't
do it from a fighter though. They can put you on it from the ground, though.