BAE Systems Inches Out In Public On Electronic Warfare

[hornetfinn]

That's true in chirp type radar, although the effect of increased processing gain and the need for jammer to use wider bandwidth to counter this far outweight the negative effect.

Iam not sure if processing gain can really counter the negative effect of spreading signal over wide frequency range though.For example : if radar can operate between 8-12 Ghz ,it operating frequency jumping randomly 4 Ghz total bandwidth , unable to predict pattern , jammer has to distribute energy over the whole frequency range, for a normal pulse with bandwidth of only 1 Mhz ,then only 0.025% of jamming power will get into radar receiver. For a compressed pulse with 1 Ghz bandwidth ,about 25% of jamming power will get into radar receiver. That quite a big different of around 30dB

This is handled with the matched filter or pulse compressor which basically amplifies the received radar signal while noise level isn't amplified that much as it doesn't match the filter. Certainly barrage noise jamming will have some effect on pulse compression radars, but far less so than on radars without it. How much exactly depends on how the pulse compression is done and other properties of radar. Usually modern jammers will do jamming against far narrower bandwidths at any one time to get enough jamming power through. Still modern radars can burn through such jamming at pretty significant distances away against regular RCS targets. This is why more elaborate jamming methods are used, although noise jamming certainly has its place.

Yes, phase combinations are very limited. In binary phase codes it's as name suggest binary with two states. Polyphase codes can have more states, but it's still limited to fairly small number of states. Anyway, in phase coding a long pulse is divided to extremely short subpulses which are coded by varying the phase.Using phase modulation system it's possible to transmit more information than using frequency modulation as it allows more efficient use of signal bandwidth to transmit information

According to this http://www.radartutorial.eu/08.transmit ... on.en.html phase coded pulse compression seem to have very low compression ratio ,maximum value is only 13 ( or is that only for Baker code ? )

That's true only for Barker codes and I'm pretty sure no modern military radar uses these codes only. Being at best being 13 bits long and having only handful of codes makes the Barker code predictable and susceptible to jamming. Barker codes are so called optimum codes (not all of them are, but still) as they provide low sidelobes which are all equal in magnitude. There is nothing preventing using longer codes with slightly reduced sidelobe performance.

Please read this, it's the best article I could quickly find: http://dspace.mit.edu/bitstream/handle/ ... sequence=2

Another good read: http://www.acfr.usyd.edu.au/pdfs/traini ... lution.pdf

[hornetfinn]

I guess the jamming is part of the story. Also being able to detect and exploit holes in the IADS.

That too, definitely. IMO it's like this:

1. F-35 is far more capable of detecting and precisely locating threat systems than any fighter before it
2. With this knowledge it can position and orient itself for maximum effect
3. With very high gain and high power antenna of the AN/APG-81 it can put highly effective jamming against engagment and fire control radars. Even using very small part of the APG-81 for jamming purposes will beat legacy self-protection jammers easily. Using large part of APG-81 for jamming will mean jamming capability almost equal to dedicated legacy jamming platforms (in higher frequencies at least).
4. VLO stealth allows it to get much closer to threat systems to put even more effective jamming against them to protect following 4th gen aircraft

Combination of all this is make F-35 pretty much unparalleled EW system ever. Even if some dedicated jammer aircraft might have even more powerful EW systems, they will have to stay much further away from threat systems as they themselves can easily be detected and targeted because even the most powerful EW systems can't overpower radar systems if RCS is high. Another huge advantage is that they can work as one coherent force and there will be a lot of F-35s around. I don't think many people understand how big effect all this will have on combat performance, especially when 4th gen aircraft are used alongside F-35s.

[garrya]

thanks alot for those informative links hornet, i will look at it and added useful info to my blog

[spazsinbad]

DARPA Ups Funding For Autonomous Electronic Warfare Work
03 Nov 2016 Colin Clark

"WASHINGTON: DARPA is taking another step toward building autonomous electronic warfare systems with a small contract award to BAE Systems.

Artificial intelligence and autonomy loom large in the Pentagon these days. And electronic warfare, much more quietly, dominates a great deal of thinking across the services these days after we’ve watched how the Russians operate against Ukraine and in Syria. So DARPA’s additional $13.3 million award announced today is worth noting.

Why does all this matter? One of the biggest challenges facing the F-35 program, for example, is the creation of a huge digital threat library (known as mission data files) for the airplane. It includes electronic spectrum information for a wide array of emitters — radar, radio and other sources....

...Bear in mind that much of EW work and related funding is highly classified, so what we see in public is just the tip of the electromagnetic iceberg." [BEST READ IT ALL AT THE URL]

GRAPHIC: "Conceptual graphic of DARPA Adaptive Radar Countermeasures (ARC) by BAE" http://breakingdefense.com/wp-content/u ... by-BAE.jpg

Source: http://breakingdefense.com/2016/11/darp ... fare-work/

[spazsinbad]

HASC EW Expert Bacon: US ‘Not Prepared’ For Electronic Warfare Vs. Russia, China
08 Jan 2018 Sydney J. Freedberg Jr.

"...Russia & China
The high-end fight, of course, will be even harder. Traditional “stand-off” jammers aren’t stealth aircraft, so they rely on keeping their distance from anti-aircraft threats. That keeps getting harder and more dangerous as Russian-made surface-to-air missiles grow in range, with the latest round for the S-400 Triumpf system claiming a reach of 250 miles. The old Air Force Compass Call and the new EC-X, the old Navy Prowler and the new Growler, are all at risk. (So are other support planes such as AWACS).

That’s why the US needs “penetrating” jammers, Bacon [Rep. Don Bacon, a retired one-star general] said: stealth aircraft that are harder – though hardly impossible – to target and which can slip into enemy airspace to conduct electronic warfare at shorter ranges.

Would that mean the F-35 Joint Strike Fighter, which has much-touted but publicly unknown EW capabilities? Perhaps, Bacon told me, emphasizing he had to keep far away from any classified materiel. In the near-term, though, he is most interested in the F-35’s potential as “a giant sensor package,” stealthily conducting reconnaissance ahead of the main force.

No one aircraft will solve the problem, he emphasized: The US needs a “balanced force” of both manned EW aircraft and drones, both stealthy and non-stealthy. “Stealth is not the silver bullet by itself; stealth has to be surrounded with EW support,” Bacon said. (Stealth reduces radar signature but can’t eliminate it). “Before you get a B-2 or B-21 over the target, it’s going to take some EW support as well, in the high-end fight.”..."

Source: https://breakingdefense.com/2018/01/has ... sia-china/

[alloycowboy]

Electronic Warfare: The Part Of The F-35 Fighter Story You Haven't Heard

https://www.forbes.com/sites/lorenthomp ... 2c049068cc

[steve2267]

Electronic Warfare: The Part Of The F-35 Fighter Story You Haven't Heard

https://www.forbes.com/sites/lorenthomp ... 2c049068cc

Article is very positive / complimentary of the F-35's EW capabilities and provides good, generalized descriptions of those capabilities in terms the average layman can grasp.

I did like this part in particular:

Three distinctly different variants of the plane will supply each service with performance features tailored to their unique requirements, [i]in an exceptionally agile and versatile aircraft designed to be far more survivable than those that came before.[/i]

Some are now starting to publicly recognize and describe the aircraft as agile. Hurrah!

[spazsinbad]

Some quotes I like from article above by LOREN THOMPSON (LORD OF THE EVIL F-35 PUBLIC RELATIONS EMPIRE!)

"...The F-35's electronic-warfare system is built by BAE Systems, Inc., the U.S. subsidiary of Britain's biggest defense contractor. Like F-35 prime contractor Lockheed Martin, BAE Systems is a longtime contributor to my think tank and consulting client. But the company is so reserved in discussing features of the system that I didn't bother to solicit comments for this story. Fortunately, there are a few other sources one can turn to for a general grasp of how efectively F-35 maneuvers in the electromagnetic realm.

Unlike legacy tactical aircraft that had "federated" electronic-warfare systems, the F-35 architecture is highly integrated. Radio-frequency and electro-optical receivers are embedded around the edge of the airframe to provide continuous sensing of hostile emitters in every direction, with collections from all sensors fused through a central computer before being displayed on the visor of the pilot's helmet. The system also merges information from of-board sensors to provide a comprehensive picture of the local electronic environment.

F-35 is the first fighter that integrates threat data from across the relevant segments of the spectrum before displaying it to the pilot. That reduces the time required to respond to dangers while also easing pressure on the pilot. In fact, if the pilot is preoccupied with other facets of the mission, the EW system will automatically generate the optimum solution to a threat, whether that means jamming a radar, releasing chaff to confuse it, or launching false targets (usually hightech flares) to draw away heat-seeking missiles....

...Because the F-35's EW architecture is fully digitized, it weighs less, needs less space, and requires less power than legacy technology. However, the F-35 provides much greater electrical power for electronic applications than last-generation aircraft, enabling it to collect information and generate efects over larger areas. The radar is designed to generate highly directional signals for jamming so that emitters in specific locations can be disrupted without causing collateral efects elsewhere in the battlespace...."

[michaelemouse]

About VLO jammers: I get that having VLO would be useful to sneak into a stand-in jammer position but once you're emitting the jamming signal, are you're likely to give away at least your direction to that jammed radar?

One of the ways LPI radar stays undetected is by having very low power signal and AESA can be excellent at focusing power in a pencil beam to have high effective radiated power but if you're jamming an enemy radar, there still has to be a significant amount of power that reaches the victim radar from your position.

Hasn't there been a trend for stand-in jammers to overwhelmingly be drones or munitions?

[jetblast16]

The radar is designed to generate highly directional signals for jamming so that emitters in specific locations can be disrupted without causing collateral efects elsewhere in the battlespace....

Directed Energy

[sferrin]

Some quotes I like from article above by LOREN THOMPSON (LORD OF THE EVIL F-35 PUBLIC RELATIONS EMPIRE!)

This is the same guy launching all kinds of baseless innuendo against SpaceX with regards to the Zuma launch. (SpaceX is in the process of leaving ULA in the dust.) I've come to the conclusion he pretty much says what they pay him to say. (Boeing and LM -ULA partners- both contribute to his think tank.)

[white_lightning35]

I didn't know where to put this so I chose here.

https://www.forbes.com/sites/lorenthomp ... 047b0a3ec8

Thoughts?

[SpudmanWP]

Sorry, but no.

His reasoning for not re-competing the ESM was weak. Given the source, my first thought was "Is BAE sponsoring him now"?

[steve2267]

All of Loren Thompson's arguments would seem to apply to DAS as well, yet LM is switching DAS to Raytheon.

I don't think I buy Thompson's arguments at their face, but these sorts of decisions do represent risk. LM has developed a great aircraft in the F-35; I hope they don't muck it up now.

[SpudmanWP]

Worst-Case they go back to BAE