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Will a noise jammer block the fighter's own radar? If I have understood it, a noise jammer, e.g., a barrage jammer, will emit a noise signal across a wide frequency band. Won't this make it hard to interpret its own radar "hits"?

I and a buddy are trying to make a more advanced Mech game where we want to model the ECM war a bit more. So we are trying to learn :).

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If you are emitting RF, you can be seen. There are two ways to emit RF: 1. Transmit (or leak) a RF signal, and 2. Reflect a RF signal.

A jamming device emits (usually) high amounts of RF, with the general idea that the receiver of someone's radar unit will be desensed or otherwise overwhelmed by the signal. Like putting a multicolored sun into a small dark room.

So with multiple receivers (as in multi-static radar) a jamming aircraft can normally be rather precisely located (assuming omnidirectional uniformity of the jamming signal).

When noise jamming, your aircraft may not broadcast on, near or on harmonics of a given frequency within a temporal frame of when you are emitting on that frequency, so your receiver has the opportunity to detect returns. More importantly, your noise emitter may drop power and your radar receiver may have cans (well, cavities) tuned to protect the sensitivity of your radar receiver when expecting a return signal.

There are many books on radar technology, but I believe EW102 covers radar, deceptions, noise jammers and other techniques in a manner that most mildly technical people can read and understand. There are other books, but I use that series in an Electronic Warfare course I teach, and they are reasonably current. The open literature is rich with advances in jamming and other stealth methodologies that have advanced tremendously in the last 50 years.

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    $\begingroup$ The use of multi-static arrays or constellations adds complexity to a solution to the source of the wideband noise. Such jamming is not typically run in a continuous mode in today's environment, and when used intermittently, is against an imminent threat, where the objective is very near term. The idea is that the threat (eg missile) is run out before a solution can be obtained. Regardless, there are many different types of jamming, with applications in different scenarios. No one technique works universally. $\endgroup$
    – mongo
    Commented Aug 1, 2017 at 13:44
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    $\begingroup$ @Notts90, a multicolored sun is an expression used to indicate a very bright emitter, which has many different frequencies (colors). RF is radio frequency and generally refers to energy emitted in the radio frequency spectra. For example the emissions of a transponder is RF. The emissions of radar are RF, and even the emissions of a jammer are RF. In these three examples, each RF source has normally increasing ERP or effective radiated power. $\endgroup$
    – mongo
    Commented Aug 2, 2017 at 12:12
  • $\begingroup$ @mongo what do you mean by EW102? What other books are there to read more about this topic? $\endgroup$
    – mike
    Commented Dec 5, 2017 at 19:34
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    $\begingroup$ @mike - EW 102 a second course in electronic warfare: hollis.harvard.edu/HVD:everything:TN_skillsoftbke00000562. Intro to Modern EW is also good: hollis.harvard.edu/… $\endgroup$ Commented Dec 5, 2017 at 19:46
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    $\begingroup$ @HephaestusAetnaean has it right. Adamy has 4 books up to EW104. We use them in EW courses. $\endgroup$
    – mongo
    Commented Dec 5, 2017 at 19:53
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That's not the nature of how ECM works.

Here's a primer on basic electromagnetic countermeasures as was used during the Vietnam War.

Since ECM, or radar jamming, works by analyzing incoming radar energy, identifying it as a hostile emanation and the transmitting a counterfeit signal, the system quickly filters out friendly radar systems and does not duplicate their signals

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    $\begingroup$ Thank you. I had found that video and saw through it. Do most of the fighter planes use Deception Jamming? I had found this article ECM that mentions both forms. And it mentions Frequency-hopping as a common counter-countermeasure to deception jamming. Noise jamming seems "safer", in the seance that you are actually always jamming, to an degree. But i will drop the point if all fighters do indeed use deceptive jamming :). I mean the video, while good, is a bit old. $\endgroup$
    – user16077
    Commented Jul 31, 2017 at 20:02
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Noise jammers will either have a filters to block out the frequency used by your own radars or there will be a "blanking" circuit to temporarily stop the noise jamming for a brief time to your radar operate.

Noise jammers are not as effective as they used to be. Back when radar had mechanically rotating antennas and relatively slow gating, the constant amount of noise prevented the radar from determining the direction or distance.

Most modern radars can easily distinguish noise jamming and ignore it. Also there are many weapons that will actually home in on the jamming signal since it is continuous.

Deception jamming is far more effective again modern radars, but there is a constant battle between Electronic counter measures (ECM) and Electronic Counter Counter measures (ECCM). so better radars need better jammers to counteract them.

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