111–120 of 243 posts
What I want is a tiny portable bluetooth jammer for those who insist everyone in public must be listening to their music. Sadly they are too clunky to haul around each day.
https://github.com/cifertech/RF-Clown
You can use their files to make one via a pcb vendor like jlpcb or you can look for someone who has already done that:
https://www.tindie.com/products/ryanyu/rf-clown-v20-esp32-wi...
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> Additionally it cannot provide coverage over oceanic areas. It's really hard to jam oceanic areas though, you need a vessel capable of sustaining human life autonomously at least for days plus dealing with the high seas. Buoys could theoretically be used for that purpose, yes, but good luck getting them stationary enough. Maybe some of the secret services could pull off such a trick but at least no ordinary civilia…
> sustaining human life Not really. Drone ships are very much a thing these days.
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There are two types of GPS jamming. There's GPS jamming by the military, mostly in war zones. This seldom effects airliners because they steer clear of active war zones. Then there's GPS jamming by delivery drivers who don't want their boss watching over their shoulder all the time. When the article mentions jammers as small as a cellphone and costing less than $100, those are sold to drivers. Delivery drivers don't…
GPS jamming is fairly detectable right? I wonder if we could create some crowd souced map of jammers. I think this kind of already exists as fairly course data but if a bunch of people installed fixed GPS sensors at home and wired them up to note every time their location lock is lost or moves. It could create a hyper detailed map of where the jammers are and track them moving in realtime.
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IIUC, GPS picks one satellite and 3 more to establish time differences between the first one and the other 3. There's only one point in universe where the set of differences would match what was observed, given the broadcast orbital data of satellites, and that gives the location of the receiver. It's like you are provided radii and center coordinates of 3 circles on a paper that intersect at 1 point and you are to m…
Coherency is a state. My question is if that state can be achieved by just tuning the individual clocks/locations based on GPS as a master. And, there's other tricks, with all the inter-satellite communication [1]. And, there's a contextual difference here between civilian GPS and military GPS. Much of the precision in the existing GPS satellites is to support the military use of GPS, with intentionally error injecte…
https://www.ti.com/product-category/clocks-timing/clock-netw...
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Jam resistance and spoof resistantance are very different. What work is done to make GPS more jam resistant?
https://gps.stanford.edu/research/current-and-continuing-gps... Single element antennas, adaptive antennas, beam steering antennas. Basically attempting to pull good RF while avoiding bad RF. (this has been applied in the Russo-Ukrainian war in modified Starlink equipment) GPS antenna mods make Starlink terminal immune to jammers - https://news.ycombinator.com/item?id=39616417 - March 2024 (72 comments) https://olegk…
https://www.gpsworld.com/todd-humphreys-russian-satellites-a...
I wish there were cheap Bluetooth jammers to prevent speakers from playing when hiking
Whats really sad for aviation is there was already an extensive network of ground based navaids. As GPS has proliferated, they've slowly been decommissioned as they age out to save on cost. I'm specifically referring to VORs which provide azimuth and range to station. GPS is fantastic and as a primary source everyone loves the benefits it brings. However, in a century of aviation, everyone has kinda sorted out that y…
Although that approach depends on you being able to see the ground neither of which is guaranteed over a body of water or in poor visibility.
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Seems like we'd need a modern version that's less susceptible to jamming, otherwise aren't we just replacing one jammable service with another?
There are two types of GPS jamming. There's GPS jamming by the military, mostly in war zones. This seldom effects airliners because they steer clear of active war zones. Then there's GPS jamming by delivery drivers who don't want their boss watching over their shoulder all the time. When the article mentions jammers as small as a cellphone and costing less than $100, those are sold to drivers. Delivery drivers don't…
Btw, don't smartphones have this built in? I remember some old and cheap Android phones without GPS that came with this.
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Seems like we'd need a modern version that's less susceptible to jamming, otherwise aren't we just replacing one jammable service with another?
There are two types of GPS jamming. There's GPS jamming by the military, mostly in war zones. This seldom effects airliners because they steer clear of active war zones. Then there's GPS jamming by delivery drivers who don't want their boss watching over their shoulder all the time. When the article mentions jammers as small as a cellphone and costing less than $100, those are sold to drivers. Delivery drivers don't…