Expendable jammers, EW in general


I meant to write about this electronic warfare topic for a long time, but now I suppose it's just as fine to just push readers towards looking it up:

There are - and have been for a long time - expendable radio jammers which are very small (artillery grenade or 'much less than backpack' small) and relatively cheap. These jammers can be used to knock out radio comm in a radius of several hundred metres. Emplacement is typically by hand or howitzer.
Imagine a late 80's scenario for example: An armoured battalion battlegroup advances along a road in a South German landscape (woodland hills left and right, with only unpaved forestry roads - and a paved road in the valley where there are also buildings between the agricultural areas). The defenders activate several radio jammers near the company-sized vanguard and a tank platoon lying in a flanking ambush opens fire. Valuable seconds of return fire lag are gained and doom the vanguard.
The effect would have been complimentary in a similar way as the combination of HE/DPICM and scattered mines would be; the targets would be very much restricted in their ability to cope with the challenge.

Another example: An infantry platoon is meant to raid a picket and take prisoners and radio sets for intel. A few expendable jammers are used to isolate the picket and to keep it from calling for help.

Even some experienced and longtime-serving officers don't happen to know about this and EW is in general still a black box to many. This may be part of the reason for the excessive reliance on radio comm and electronics these days.

So here are a few links, just in case you're interested in peeking at the stuff a bit:

About the hand-emplaced HEXJAM

Russian 3RB30 (couldn't find worse link, obviously)

About artillery-delivered SAMEL 90, Bulgarian version of Russian 2RB30

Electronic warfare in general:

For German, Austrian and Swiss readers:
(Band 17A; boring, but acceptable)






  1. Electronic warfare is presented as a measure of extremely powerful broadcasting that disturbs intelligible enemy communication.
    It will be observeable far beyond the limited area where it has jamming capabilities. While the information does not precisely give the whereabouts of the attacker, it is obvious that an attack is going on - calling for a counterstrike. Thus electronic warfare does require some kind of "ambush" against the quickest sorts of replies due to the information obtained by broadcasting hostile jamming.
    Fiber optic cables for communication will be increasingly important under these conditions. Laying a network of these enables short range broadcasting that will be ever harder to jam. Add some direction to the way energy is transferred and jamming requires ever increasing amounts of energy and good emplacement with intelligence about the directions of enemy broadcasting. Thus a grid of sender and receiver stations on a fibreoptic network with directed wireless transmission could defeat most attempts at tactical jamming if employed appropriately. Such secure fibres for communication even enable to set up traps for an opponent who relies on jamming in order to mute information transmission during an attack.

    Disposeable EW systems sound like a good idea, because they will have a hard time avoiding precise strikes. The presented versions are however static and limit the area of muted enemy communication. Unforseen positioning of communication infrastructure can doom such a static EW set up.
    Battery powered UAV might be among the tools of choice for setting up mobile jamming. Take for example the Camcopter that can fly low and slow, give it a powerful battery pack and a short duration EW suite. The mobile jamming pack is meant to operate during a short time, in packs switching on and off in their transmission in order to avoid precise localization for counterstrikes. This gives some capability to react on unforseen circumstances at a much higher price tag.

    All EW is information and by its interaction with the surrounding world it creates even more information. Can so-called passive radar systems work with EW broadcasting alone? This would mean that an area of jamming is also an area of radar switched on. Wouldn't this offer a useable combination with air defence?

  2. While EW is a bit of a black box to me, I've always understood that when it comes to jamming, you can jam a receiver but not a transmitter. Thus, in your first example, jammers would keep the vanguard from communicating internally, but wouldn't have the range to keep the vanguard from sending messages to the main body (though it would be one-way communication). In your second example, the picket would be able to send messages to whatever it was protecting, but again would not be able to receive messages. Any decent picket would double-bank its comms and also have field wire laid down. You can't jam a phone!

    I see such jammers as being better used against enemy command posts (keep the HQ from receiving reports from troops in contact and so preventing effective coordination) or to augment the barrier plan as you turn the enemy into a kill zone, or to add chaos to a pursuit (in conjunction with scattered mines).

    1. You always jam the reception. If someone is sending a signal with an energy amount of 1 Joule jamming means it gets scrambled into something unreadable by a jamming transmission at 100 Joules in the same direction (Jamming equals shouting much louder, so you do not understand a word said).
      Sending at as high energy output as the jamming signal gives excellent SIGINT for all observers and defeats your camouflage by other means.
      Jamming can be done with high energy output during a short time period or with a massive mobile energy source such as a giant warship and to a lesser degree by a flying aircrafts that create lots of energy with low weight systems.