ECM's

[Wraith27 6]

Hello!

 

Tell me please what is the differnce between noise-jammer and deceptive-jammer. In game of course. Does one is better for SAHM and second for AHM. Does home-on-jam is for both of thise jammers etc?????

 

Thanks!

[JediMaster 451]

I didn't know the game featured deception jamming. Pretty much every flight sim I can think of has represented noise jamming only.

[MigBuster 2,861]

In the Weapons Editor you can select your Jamming pod to do one or either - although I suspect pods in the real world may be able to do both. Whether it works in game (like the HOJ option) Im not sure.

 

 

There was a bloke who claimed to work in this area came on here a while back with some interesting things.

 

"Most sims have a fairly decent representation of deception jamming. Noise jamming I don't think I've seen in any sim except Jane's F/A-18. Incidentally, it also has towed decoys, so if I had to choose a sim with the best EW modelling it would have to be that one. If Falcon 4 has noise jamming modelled I haven't noticed. Only played LOMAC a little bit so I really can't say there.

 

 

The most modern ones are pretty simple operating wise. Turn them on when you get over Indian Country and leave them on until you fly out. They stay silent until a valid lock from a threat emitter is detected, at which point it can safely be assumed whatever cover you had is blown, and throw out some deception jamming. Done properly, deception jamming shouldn't offer a target for HOJ missiles* as the jammer is simply mimicking the threat radar's signal (hence the 'deception' part).

 

The idea is for the jammer to 'seduce' the radar's track gate, then walk it away from the jet. Which is why you sometimes hear deception jammers referred to as 'gate stealers'. If your advantage in jamming is large enough, the missile will miss completely without any further action required. If the threat radar is particularly capable (or your jammer a POS relative to it), then you'll have to hope for a increase in miss distance while you do the missile avoidance drill.

 

More advanced jamming systems are alleged to have an active cancellation capability, wherein they take a threat signal and broadcast an exact copy 180 degrees out of phase, cancelling it out. Of course, due to limitations just how large a transmitter a fighter could haul, it wouldn't cover every radar out there (unless we've done some real miracles in EW technology), but it could conceivably cover enough to provide a VLO-esqe penetration capability to conventional aircraft.

 

Noise jammers are a whole different ballgame though the objective is the same. Noise jamming could be compared to blasting someone with a fire hose so they don't realize it's raining on their head. The further away the hose is, the weaker the spray and the more likely they are to notice raindrops. If the raindrops increase in size (RCS) the hose's spray needs to be stronger to cover them up. Of course that isn't a perfect analogy, because it's generally lopsided in the OTHER direction, with the hose being relatively weak while the rain is strong, but hopefully I got the point across.

 

There are a few counters to it, frequency diversity/agility/hopping, alternate tracking methods such as IR or EO, home-on-jam missiles, but for the most part it's something you learn to work around. Frequency shifting techniques are good because it forces the jammer to either play catch-up to your freq changes or waste a lot of power covering your full operating spectrum. Dual- and multi-band radars really shine in this sort of arena, because the have a huge range of freqs compared to legacy radars.

 

* Regarding HOJ against aircraft: You really shouldn't be happy if a missile goes HOJ, especially at long range. In real life, HOJ removes target range from the missile, creating a situation where the missile has to fly lead pursuit throughout it's flight. At longer ranges, that means that even slight variations in the target's heading equate to large variations in the predicted intercept point. And since the missile doesn't know how far away the target is, it reacts to those variations as quickly as possible, G-ing away it's energy in an effort to maintain lead pursuit on the target.

 

In contrast, with range data available (ie not HOJ), the missile is able to fly a much smoother, more energy efficient proportional navigation course to intercept, only switching to high-G manuevering when the intercept point is suitably close. More energy in the terminal phase of flight, a better chance of getting that aircraft inside Region R and filling the sky with hair, teeth and eyeballs."