B-2 requires $1B radar upgrade

I put a thread about bandwidth and the military in breaking news, but am going to throw this out here too.

In a 2008 auction, the FCC sold the bandwidth for the AN/APQ-181 radar used on the B-2 to an unknown company, owned by a Russian educated person in Mali. This is going to force a $1B radar upgrade on the B-2 fleet.

This isn't the only system with the problem, but it appears to be by far the most expensive upgrade required by the problem. The Japanese PAC-3 system radios use frequencies that the Japanese cell industry uses, as well as several other well known systems.

Spectrum Squeeze for the B-2
Bandwidth problems

[edit on 3/26/2009 by Zaphod58]

Crikey.

Now thats just plain dumb. Incredibly dumb. They sold off the bandwidth? IS that common practice and if so, why didn't they check out if it was used first?

$1billion needed when the world is on the brink of global financial meltdown...

You couldn't script comedy like that

reply to post by neformore


This is the first radar system that I've heard of this happening to. One of the reasons that it's so bad is that the stealth radars jump around frequencies so much to avoid detection, so that makes it harder to keep bandwidths clear.

One of the interesting things in the second article was that if two or more F-35s are flying at the same time, nothing else in the Western US could be flying. And this is after they "fixed" the bandwidth problem with them.

Well, at least there will be less contrails, eh?

Both stories make the US military procurers and overseers look as dumb as a box of rocks. You'd think that someone, somewhere would have realised the potential problems....

The world is going mad.

Zaphod58,

You know all about this sort of stuff and I figured I should ask you a few questions.
But before I do let it be known that I know very little about radar, especially in the circumstances the article is talking about regarding the B2. The article is a eye opener for me since it educated me about a lot I didn't know about radar. but here's my confusion.

The bandwidth. I figured that radar used specific bandwidths, but I always assumed that the bandwidth could be modulated or changed so the radar would be more adaptive to unforeseen contingencies or even foreseen ones. I was surprised to find out that the bandwidth the radar used could even be available to the civilian sector let alone to most military sectors. Let alone that event interfering majorly with the radars operation.

If the radar uses only one bandwidth wouldn't it be very easy to track the aircraft when it's using it's radar by using maybe even passive arrays to detect that specific radar frequency?

Is the broadcasting of radar from a source outside the B2 on the same bandwidth the B2 is using basically the same thing as flooding a room with infrared light to blind a night vision camera?

Please help me get a grasp on what the article is discussing. I'm sorta not following the logistics of the problem entirely. Due to my lack of knowledge regarding radars applications for navigation or detection. I get the general principles but not the details, as I'm a little naive to them.

Thanks,

Bassplyr.

Originally posted by BASSPLYR
If the radar uses only one bandwidth wouldn't it be very easy to track the aircraft when it's using it's radar by using maybe even passive arrays to detect that specific radar frequency?

Is the broadcasting of radar from a source outside the B2 on the same bandwidth the B2 is using basically the same thing as flooding a room with infrared light to blind a night vision camera?

IIRC the B-2 frequency jumps the radar to keep it LPI. The problem is that the less bandwidth being used, the less noise energy that is received. So if they have to expand their bandwidth they get more noise energy coming into the radar. That means that they have to leave the radar on longer to get the information they need. The longer the radar is on, the more likely it is to be detected.

You want to keep the receivers bandwidth as low as possible to keep the noise energy out.

Originally posted by neformore
Well, at least there will be less contrails, eh?

Both stories make the US military procurers and overseers look as dumb as a box of rocks. You'd think that someone, somewhere would have realised the potential problems....

The world is going mad.

I realized the world was going mad when the USAF started selling KC-135s when they had fighters sitting parked for weeks waiting for a tanker.

This only seems nonsensical and incompetant when one works from the presumption that the US government is in fact doing their best to protect Americans by preparing to fight a potential future conflict against a major power. Once you start considering that the US government ( Since at least the bigger bush) is doing whatever it can sneak past the American public to rob American citizens of both conventional warfighting powers as well as strategic power projection capabilities this all starts to make sense.

But who would think like that; just ignore the crazy guy who's suggesting that they the rich and powerful can't be incompetant and or stupid as well!

Stellar

I get it now zaphod,

thanks.

It's possible that not too many people in charge of marketing and selling bandwidths for the FCC just aren't in the know regarding what bandwidths the B2 operates on.

Or it's all just a fancy cover to justify installing some really new and advanced radar system. And getting the OK from congress or whomever is in charge of that stuff would have been hard to do. THe old radar might still work just fine, but this new system might be really killer but getting it installed and paid for might have been tricky. So it's possible this is all just a cover.

reply to post by BASSPLYR


Ah, but that's the kicker. Raytheon already had a contract to upgrade the radar to AESA on all the B-2s. But they had to stop, and alter them all because of the bandwidth sale. They had the new sets on 6 aircraft if I remember correctly, flight testing them.

What about the use of phase conjugance in radar to both amplify and lock on to faint radar signatures. Does that reduce the output the radar (B2's) needs to get a return or does it still have to go through the initial high output phase to find the targets in the first place which is where the B2 could be more vulnerable.

reply to post by BASSPLYR


That is a good question. I doubt that you'll be able to find much information out there about the way the radar works.

About all I know about the new system is that it's not changing the processing or signal, or any new capabilities, but it does lay the foundation for future growth. They have two antennas mounted in the leading edges, and use the radar for weather, aircraft deconfliction, tanker rendezvous, and station keeping.

The B-2 is fitted with an AN/APQ-181 radar, with some similarities to the AN/APG-70 used on the F-15E Strike Eagle fighter. The AN/APQ-181 is a Ku band (high microwave, from 12 GHz / 3 centimeters to 18 GHz / 2 centimeters) radar, with an electronically steered antenna in the lower leading edge of each wing. The Ku band suffers from greater atmospheric attenuation than lower frequency bands, but it also provides very high resolution for navigation and targeting.

The AN/APQ-181 provides "low probability of intercept (LPI)" operation, with the radar dancing over frequencies and changing pulse patterns so that its signals can't be picked out of background noise until it's too late. Apparently the TACIT BLUE program did much to advance LPI radar technology; it would have made absolutely no sense to design a stealthy battlefield surveillance aircraft and then have it announce its presence by blasting out strong and easily detected radar signals. The AN/APQ-181 provides 20 operational modes, including a "Synthetic Aperture Radar (SAR)" mode for ground mapping, with a "Ground Moving Target Indicator (GMTI)" capability; a "Terrain Following / Terrain Avoidance (TF/TA)" mode for low-level flight; a mode for spotting and linking up with a tanker; and weather mapping and navigation modes.

www.vectorsite.net...

Liked that link you just gave.

I too doubt that there will be much info anywhere on how the radar works other than the barest gist.

Interesting. One can find lots of info on phased conjugance for optics but not for microwaves, although there are lots of applications for this phenomena combined with microwaves. apparently its a pretty useful little trick, but no bodys saying much about Phase Conjugance applications outside of optics. Not convinced I know why either, but I suspect it's because it's a useful tool for locking onto very small radar returns that are elusive (other stealth/foreign stealth tech), amplifying the return and making a lock onto the target so that it's near impossible to loose the lock. (based on the physics of how the phenomena works) Once it's got you...it's pretty much got you. I believe we also use it for satellite tracking, and for very secure microwave transmission for communication...along with some other uses that are speculation but pretty fantastic if true.

of course there is another small minor detail from that article - outside of the USA , the AWACS have limited operational use due to other equipment using the frequency they operate on.

But yet NATO has 17 (18 purchased 1 lost in Greece) officially owned by Luxembourg based in Germany. France has 4, the RAF has 7, and Saudi Arabia has 5 E-3As and 8 KE-3As (E-3s without the radar, added a boom and two drogue pods).

That's comes up to as many as the USAF has in inventory, by countries outside the US. They must be pretty effective out there, or they plan on just using them in the US.

The problem from the article isn't with AWACS, its with JTIDS from the AWACS to the F-22. Once the newer systems come online, it won't be a problem anymore.

[edit on 3/27/2009 by Zaphod58]

[edit on 3/27/2009 by Zaphod58]