BLUEMOMENT

I hadn't realised that GPS jamming devices are popular with both criminal gangs and lorry drivers who are trying evade the scrutiny of GPS-based fleet management systems. Seems the jamming gizmos can be bought online for £50. More here (you don't need a subscription - you can access 10 articles per month for free).

Anyway it seems that the growing popularity of these devices is causing some worry to the powers that be, and one consultant estimates that there will be a serious incident in the English Channel within ten years.

Injecting false positions could be much more fun. I know it has been done in the lab, but I'm not sure it has been demonstrated in the field.

Anyone found a way of jamming a windvane yet, short of hammering a wedge into its works?

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Never attribute to malice that which is adequately explained by stupidity - Hanlon's Razor
But don't rule out malice - First Corollary to Hanlon's Razor

And what prey is the benefit of damaging someone's self-steering? Or were you for some obscure reason thinking of sabotaging one of those graceful wind turbines?

I think sir has perhaps failed to pick up on the rather weak wordplay in mr geek's post. Something to do with the multiple meanings of jamming?
For myself I was looking forward to seeing and hearing large numbers of rastafarian-skippered vessels chugging around and jammin', jammin'....

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Ken
Rival 38 Cherry Ripe
Yes, isn't it odd that a boat named like that should be green?

I'm sorry you're not feeling better yet. Get well soon!

We've got a couple of GPS signal generators at work which give a spoofed fix at a range of literally 3-5cm. Which is frustrating in the extreme. A 100 foot range would be brilliant and the fact we don't have it makes me think it's very hard to acheive or illegal. It can't be a problem of signal level because as we know the signal levels are tiny - below the noise.

Personally, I think spoofing a credible moving position on a vessel would be impossible unless you had feedback from the vessel. Spoofing a time and date on a fixed station in a bank might be easy if you had the range but surely these numbers are sanity checked with a local quartz clock and/or an clocks in other locations?

I find the idea of ships getting lost in the Thames Estuary or hitting each other in the channel because of lost or innacurate GPS laughable. They have radar and eyes. I wonder if David Last is touting for business of some kind with a shock story?

It's also one of the holes I pointed out when the gliding world (and the flying world generally, I think) went over entirely to GPS logs for badge and record flights ... I gave up all that nonsense when they banned wind-up barographs and film cameras.

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Never attribute to malice that which is adequately explained by stupidity - Hanlon's Razor
But don't rule out malice - First Corollary to Hanlon's Razor

I think I might be making a different point with my sentence. I often need a GPS signal at work. I can't get one so I have to spoof it, but I have to gaffer tape the spoofed source 3cm from the bloody antenna and only one person can use a transmitter at any one time. Which makes me think that spoofing a position at any range is either very difficult or very illegal.

Well it will certainly be illegal unless you have a licence permitting radiation on that frequency band and using that mode and power of transmission. Such a licence won't be easy to come by I assume.
For £50 legal to own, illegal to use equipment: read also - original CB gear, ex-WD transmitters, radar speedtrap spotters, and a whole plethora of substandard domestic data propagation gear.
Stand by your beds, the stuff is out there and there's a whole lot of people who think it's fun to fek with society - think lasers and air-pilots for example.

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Just because you're paranoid
doesn't mean they're not out to get you.

Just spoke to people who know. Jamming is easy - it really is as simple as raising the noise floor at the required frequencies.

I forgot to ask about spoofing.

Can't say I can get worried about this issue. There would need to be an awful lot of vandals about with jammers before GPS got as bad as Decca was, and even if it did I'd just have to look where I was going, which I already do.

Compared to MMGW it's a non-issue.

I used to like Decca. OK, the accuracy was a lot less than GPS, but a lot better than nothing. It seemed to me a daft decision to switch off an independent, relatively cheap navigation system.

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AFAIk these jamming devices plug into the ciggy lighter and only work for a short range that affects the vehicle they are in. I suppose if you stop next to one at the lights it might affect you as well. Out at sea I think we will be safe.

Danald, What's Shard getting done to her bottom?