Find Me w/GPS?

I don't think we are there yet, but perhaps soon. Present beacon implants produce 1/10th watt or less, not nearly enough to be received by present satellites, but enough to be received by very costly receiving systems up to several miles away. In theory they can be detected by existing cell phone towers, up to perhaps one mile, by reducing the number of cellphones each tower can accommodate. Cell phone towers do locate your approximate position. They need to do this to know when you should be handed off to the adjacent cell phone tower as you drive and talk. Even when you are not talking the cellphone tower needs to know your approximate location in case some one tries to call you. The implant could send out a beacon signal identical to the beacon signal your cell phone sends out, but lower power. I think the cellphone tower sends the signal strength of your beacon signal to a central computer which could compute the location of selected people, plus or minus about one block. They may do that at present, but not when your cellphone is turned off. Neil

Well the question occured to me after reading "Every Step You Take...Every Move You Make...My GPS Will Be Watching You" by Michael Rosenwald in the current edition of Popular Science Magazine. Looks like the ability to embed a GPS in one's person can't be too far away.

the GPS must be able to "see" the satellites. Thats why GPS aint worth squat underground or in the woods, not to mention subdural. there is a feature called "Wide area acquisition" (WAAS) which does what neil mentioned using signal transfer, but it too must initially see the satellites.
We do use survey GPS units that can give us station readings as accurate as +/- 1 cm. However they take as many as 30 minutes per station reading and signal processing another known station with which to calibrate the signal. Its not as "bulletproof" as they have you believe from systems sales.

The prolem with GPS for non military use is that the satellites keep shutting off and on for housecleaning and retasking, so unless you keep current with tasking information , your accuracy could be compromised down to a +/- 50 meter r circle. Thats still an error bar of about 1.6 acres. A heat seeking missile works better.
GPS is a tech whos PR is much better than its capability. All the articles in magazines fail to tell us that theyre talking about optimal performance of clear days with all satellites pinging. Usually, you can acquire 8 or 9 satellites at any time. Without wAAS, or vHF post processing, your error is in the multi meter level. If your trying to loocate a heretofore unknown city , like Chicago, thats adequate resolution. BUT, if your trying to find and map a point or a boundary, youd be fired.
I like to play with GPS for caching and terrain mapping and I use it on my boat for plotting waypoints. I do use it in my work for coarse measurements, never anything that we rely on.
But as far as an implant, youd need a "human downlink" antenna, like one of those teeny 'mushroom" antennas that Garmin units have.

Very interesting. I had no idea the functionality of GPS was over hyped. So those units sold to backpackers don't work accurately on overcast or stormy days? Jeeze I'll stick with my trusty Silva and topo maps. Hmmm...now I'm trying to decide which ear to clip my antenna to. Anyway thanks to both for the thoro treatment of the issue.

they wont work in overcast and snow, and bad thunderstorms. we use them on boats mostly to tell speed. if a sailor relies on GPS to plot hhis course. The only thing GPS will be good for is to precisely plot the wreckage. (capt "diddy" Schmidt-pilot of the Mildred Anne)

So you could implant the chip in a todder or an Alzheimer's that you did not particularly want to find quickly?

I have read about locating stolen cars and trucks with computer chips. Does the company computer keep checking over a 24 hour period?

LOJAKS are not GPS units. they are little 2meter band transmitters. Most thieves can detect them and search the car till they find the lojak by a little device . They pull the lojak or disable it. Ive heard of one bunch in York county where they stuck the stolen lojak onto an Amish buggy.
Some of the more modern theft devices use an interface that detects that the encoded key has been overridden and that sounds the radio. This is deep within the engine or tranny so that one looks like itll stop the thieves, unless they just use a rolloff box and drag the car onboard and pickit apart after a 2000 mile trip on the back of an 18 wheeler. If thhey want your car, kiss its ass goodbye.
light trucks, especiually thhe crew cab, short body 'pickyups' are becoming very desiraqble to thieves lately.

Here in Lancaster, they are using the RFIDs to tag cows. Just like a can of beans at Wal Mart. You can keep and change production records on a cow and read it with a scanner , and, excited, I understand they have a range of a mile or thereabouts. Cows can run but they cant hide.

Farmerman--

But wadda bout them cows in the Wide Open Spaces where the cell towers are mounted on cacti?

And the toddlers and the Alzheimer's patients?

cows r on their own. We dont raise "cows" on wide open spaaces , most Pastures in the east are only about 100 acres each , or less.Anyway, the rfid chips aare ear tags not implants 9very chic, they look like little pierced pearl earrings. The ear chips dont broadcast anyrhing, they just react to a RF stimulus thats in the area, no batteries. ANd the cows look Maahhvelous, big stupid goofy cows with pearl earrings. i wish i had a pic, youd laugh .
alzheimers patients with a gps sounds reaally creepy noddy, I gotta admit, same thing with the kids. I think thhe rfid chips will be installed in us at sometime, and it probably will start with kidsor really paranoid parents. I just dont wanna think about living in that world where our fears so rule our every move. My son is a master in tai kwan do, so he will save my ass when I start wandering off in my whities.My daughter will charm them. I think about putting a chip in her social life, but Im just being an overly protective father who remembers his own boyhood. NOWAMEAN?

I friend of mine really was kidnapped by the ELN guerrilla group near Popayan, Colombia and was released after a couple of weeks. Point of this is they never even searched him or removed his watch so how about concealing a GPS unit in some piece of personal adornment, a ring say? And pray for clear skies.

a gps will only tell the kidnapped person, where he is going. It is not an instrument that notifies anyone else. Youd need a really sensitive RFID or a small transmitter that uses something besides cell phone tech. That way, passing planes or helicopters could keep a referral search band open and shooting out queries for any rfids.
Popayan, Ive passed there on the way to thhe oil fields on the Equador border. Its hilly.

How about a version of the electronic leg tags they fit onto prisoners (in the UK at least) who are released early from prison? They are quite chunky, but a sod to dismantle unless you have a masters degree in electronic engineering, or a large saw and a fast car. The parole officers can tell if they person is in their garden or house, which must be good enough resolution to within a few metres. Maybe putting tags onto kids and old people is a bit cruel and smacks of Big Brother (from "1984", not the TV reality series). Perhaps if they were smaller.