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Arthur T Knackerbracket [soylentnews.org] writes:

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Arthur T Knackerbracket has processed the following story [schneier.com]:

We’ve now had an (unsuccessful) assassination attempt by explosive-laden drones [usnews.com].

There was an attempt on the Japanese Prime Minister a few years ago.

Do not fall for the “hype” anti-drone technology is very much a joke currently.

I’ve done a walk through on why RF jammers are at best more of a last resort than crossing your fingers when you do not have advanced intel.

First of a lot of drones when they loose control go into a “short path flight” back towards what they think is their “start point”. It takes no great brains to realise that if you change the real start point co-ordinates for the attack point co-ordinates you know where the drone is going to try and land at…

Secondly you can only jam a frequency successfully in two ways,

1, Know the actual frequency
2, Put kilowatts of power up.

Radio receivers work on “energy in a bandwidth” to control RC aircraft back in the 1970’s you could use as little as 1kHz bandwidth at the upper end of the HF band. That technology still works today.

Now if you need to jam from 1MHz to more than 6GHz to jam you would effectively need more than 6,000,000,000/1,000, more than 6 million times the power at the drone mid point with respect to the operator who could without much difficulty push 100watts into an antenna that makes it directional and more like 1kW is being used.

What most of these “drone-jamers” do is work on “known control frequencies” that it is “assumed” an attacker will use.

Changing the frequency to be well out of any likely band is not that difficult…

Slightly less easy is changing the way the data is transmitted from the operator to the drone. One trick the jammer designers rely on is recognising the data format being used and try to get a jamming margin by faking the control data rather than jam it.

I could go on the list is long with tricks that an attacker could use such as using a relay drone, using an an antenna with a cardiod pattern with the deep null facing forwards so giving even more advantage against a jammer (both of which work well).

The simple fact is you have a variation of a “smart weapon” mortar attack, and the only real defence against that is “duck and cover”.

The thing about technology as a weapon of war is you obly have a short time scale advantage. Once a potential opponent knows the technology works they can “build [sic] there own” usually at a lot lower cost and faster pace…

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