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Intentional GPS Jamming On the Increase
benst writes "Here's yet another way to measure the success of GPS: by the efforts to negate it. While unintentional jamming continues to rise, intentional jamming by both foreign military forces and at-home miscreants of various stripes has shown increased vigor in the past six months. Related here are recent instances of intentional jamming on each side of the border, and (briefly outlined) one initiative mounted by the National Geospatial Intelligence Agency (NGA) to counteract it. Also, here are some ways to detect and prevent jamming."
How could they be jamming us if they don't know... that we're coming... Break off the attack, the shield is still up.
Raspberry...only one man would dare to give me the raspberry...LONESTAR!
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
Some people still think that GPS can select devices and that it sends the coordinates to the devices. But it's more like observing stars (or quasars): You calculate the position out of a timestamp from the satellites. And the only thing encrypted is the more accurate timestamp, reserved for military/people paying. The satellite doesn't really care if there are devices at all, it just sends everywhere.
I think they should be jamming GPS in some places. Or more specifically, start jamming some people's GPS. [...] I know one bridge that has been hit 12 times in the last 3 years by trucks that were too tall.
You don't need a GPS jammer.
If your bridge is 8 feet high, you simply need a metal arch 9 feet high, and a 'low bridge' sign suspended from it by two one-foot pieces of chain.
Hence, any driver approaching the bridge who should fail to notice the 'low bridge' sign will have their attention drawn to it when it collides with their vehicle, causing a loud noise but less danger than a vehicle-bridge collision.
I was with you until the significantly-less-than-the=speedlimit part.
That's just ridiculous. Speed limits are almost as a rule too *low*, not too *high* -- and on a highway, traffic moving significantly slower than the majority of other vehicles presents a hazard. A car going 5mph under the speed limit is more of a hazard than a car going 5mph over -- why? Because the slow car causes ALL the traffic moving at the speed limit to pass it, while the fast car causes ONLY ITSELF to pass traffic moving at the speed limit.
... still waiting for this free-as-in-beer free beer I keep hearing about.
Good point. A state trooper once told me that the absolute safest speed to travel was the AVERAGE speed of the cars around you. Don't go slower than the rest of the cars, and don't go any faster either.
I won't call the parent of your post arrogant exactly, but his type reminds of the people who think it's okay to drive 61 mph in a 65 mph zone in the FAST LANE.
Yeah, sure they are technically correct but intentionally and more than a bit arrogantly lack any pragmatic approach to driving on the road.
It does not matter if the law says 65. If everybody is doing 74, and some people in the fast lane insist on doing 85, then getting in the fast lane and stubbornly insisting on doing 61 creates an unsafe environment for the rest of the drivers.
I have relatives that drive on the Autobahns tell me that if somebody got into the fast lane on the Autobahn and did not get up to speed that the police would pull them over immediately and cite them. If somebody stayed too long in the fast lane, they would be cited too. The leftmost lane is ONLY used for passing. Can you even imagine if that was enforced in the US?
> Just put loads of debris in the same orbit at a greatly different speed
Unfortunately, the same orbit means the same speed - different speeds, different orbits.
You need to create an orbit that crosses the satellite's orbit at some point and wait until your debris and the satellite meet at the crossing (since their orbiting times are different, they will, if you wait long enough).
True Story - Some years back at the Telco Supplier that I worked for we had one of those Corporate awayday things at a Hotel in Bristol - We were all instructed to use the Multi-storey car park nearby. When I drove the 4x4 I had at the time into the car park I noticed one of those hanging signs notifying low headroom and drove slowly under it, relieved not to hear any scrapes..
Later, during the presentations from the PHB's, one of them confessed that he and another PHB had arrived in his new BMW X5 and when they saw the same sign he asked his passenger to get out and make sure they could pass beneath it safely.. He started edging forward as the passenger called out 'Ok, Ok, keep it coming etc.' And then they were through but he was quite disconcerted at how close the ceiling seemed to be as they drove up through the car park and he commented on this to the passenger and asked how much clearance there had been between the car roof and the hanging sign. The reply was something like "Oh none, so I just held the sign up a couple of inches.."
I think he was the Technical Services Manager...
After all, they deny lots of junk up there.
Just shoot one of them down and see who complains and THEN you'll know whose it was.
Yeah, but honestly, a driver paying attention and maintaining a preference for a truly safe braking distance isn't jumping on the brakes the moment a car slips into the lane in front of them.
Slamming down on the brakes like you describe obviously increases your odds of getting rear ended in certain situations, especially if you're driving below the speed limit. But the reality is, you're a cautious driver, you see the person indicate to pull in front of you, often taking advantage of the fact that you're going under the limit - themselves wanting to drive on the limit or above it. You aren't going to hit them, so just maintain your speed. If you know you've got someone up _your_ arse, tap the brakes so the person behind you wakes up and realises you're behaving less predictably than earlier.
Most likely, the person in front is going to get further away as they ride the limit and stick right on the tail of the person in front, while you stay safe. Less likely, you have to ease your speed down to a distance you're comfortable with. Even _less_ likely is the car infront of you has to suddenly slam their brakes on - in the moments after switching lanes - to avoid killing someone, and you smash into them. But since you're so careful, I assume you had your eye on the road ahead anyway.
tl;dr, grandpa? drive defensively, drive smart, don't act unpredictably unless it serves your interests to draw attention to yourself on the road.
GPS already uses direct-sequence spread spectrum. The military-only signal uses a cryptographically secure spreading code. Even that will not protect you from a wideband jammer with enough power. Any signal can be jammed with a sufficiently large/near transmitter. The military usually solves that problem with high explosives.
Mea navis aericumbens anguillis abundat
Um, no, it isn't. It's owned, lock, stock and barrel, by the US military. Civilian devices are allowed to access it, but the satellites are not commercially owned.
Or they could just ring up the CO of the US Air Force's 50th Space Wing, since that's who owns and maintains the current "boatload of satellites".