Quote:
Originally Posted by Dr.Sid
How does radar jamming work anyway ?
I understand that if you send the same frequency back all the time, radar can't detect target range. But it still can detect bearing, and for many applications it can be enough.
|
No easy answer to that question. There are many methods of jamming. Bearing certainly isn't enough in most cases, range is very important in naval warfare.
From this (
http://forums.frugalsworld.com/vbb/s...=jamming+works) thread, posted by mirv who is a USAF officer on an E-3 IIRC:
Quote:
Originally posted by Marlin
A radar signal is nothing more than a noise ping which has a frequency and a wavelength. A jammer trys to match the frequency and wavelength but at 180 degrees phase thus cancelling out the signal, but the jammer signal itself is a perfect source for your radar to detect.
[/b]
This is a pretty good thread. Finally some discussion that is doesn't have a lot of misinformation and someone who's done some homework. I only want to add a brief explanation about some jamming stuff. It's pretty geek, so bare with me.
And not to steal your thunder, what you've said is true from a basic point of view, but....jammers do a lot more than just that and radar energy is a bit more complex than just frequency and wavelength. Jammers have to "know" or determine a lot of characteristics about the victum radar.
The kind of jamming you described is called Inverse gain jamming and is typically used against conical scanning radars (like a AAA radar for example). Since conical scan radars use the phase of the target returns to generate error signals, an inverse gain deception jammer attempts to alter the phase (like you said) by inducing fake signals into the antennas. Also, by altering the amplitude of the signal, the jammer induces large errors into the tracking loop. To do this, the jammer must determine the frequency, PRF, and scan rate of the victum radar. It then transmits signals that change the phase and amplitude of the target signal, resulting in a signal 180 degrees out of phase with the actual target. This 180-degree error rapidly drives the antenna off the target and causes a break-lock. Cool eh?
http://forums.frugalsworld.com/ubb/ubbhtml/biggrin.gif
Like I said in another post, there are TONS of jamming techniques out there, most/all of which Falcon doesn't do...there's false target jamming, range deception, range gate pull-off, angle deception, inverse gain, swept square wave jamming, velocity deception, velocity pull-off, doppler noise, velocity bin masking, monopulse deception, skirt frequency, cross-eye, terrain bounce and some others. Falcon is generic, but at least it denies/delays lock-ons until burn through, can cause break-locks and even provides a nice "I'M HERE!" target.
http://forums.frugalsworld.com/ubb/ubbhtml/smile.gif
PD