anti theft device

[BlakesCar]

I have heard from one of my friend that Navi System can be use as a anti theft device!Is it true?There are lot of devices in aftermarket but how can i know that?

[nunya]

I would think one that's actually tied in through the car (not some stick on the windshield TomTom) could be used to at least track where your car is. As for actually being a theft disabling device, I don't know how that would be tied in. Did he mean it can actually be tied into a factory security system (which i can possibly see) or just mean maby the navigation system has its own anti-theft for the unit?

 

 

[silverton]

Basically you hardwire a GPS in to your truck, hidden somewhere with a constant 12v feed so it's always on, and you can use a website to always know where your truck is. It's like personal lo-jack, but probably better. GPS is a pretty viable option for antitheft now since it can get you as close as a meter. Thank you Clinton!

 

Well, I guess not so much anti-theft, but at least locating it after a theft has occured, as long as the battery is still hooked up, most GPS' come with a built in battery so even without a 12v feed, it should run for a day or two.

Edited December 13, 2012 by silverton

[theexbrit]

Most GPS navigation units just receive a signal from satellites, you need one that TRANSMITS a signal like they use with Onstar, etc. Most of these devices are available as a service for a monthly fee.

[silverton]

They don't need to transmit, every GPS device has a unique identifier, as long as you know that identifier and sign up on a tracking website, you can find the device. cell phones employ this technology. HTC has their own service with their Sense UI phones, but you can download apps that you pay for that will also do it. Of course the device has to be on for it to work, but as long as the GPS satellites are locked on to it, it can be found.

[BBB]

every GPS device has a unique identifier,

where can this identifying number be found? I have an old Garmin I'd like to do this with.

[theexbrit]

They don't need to transmit, every GPS device has a unique identifier, as long as you know that identifier and sign up on a tracking website, you can find the device. cell phones employ this technology. HTC has their own service with their Sense UI phones, but you can download apps that you pay for that will also do it. Of course the device has to be on for it to work, but as long as the GPS satellites are locked on to it, it can be found.

 

That's not strictly true, sure they use identifying numbers but most gps "NAVIGATION" devices can not be tracked as they are purely one-way gps recievers. Cell phones CAN because they communicate via cellular networks. Prime example being the couple that were just found after being lost for a week in the Joshua Tree desert, they had a cell phone gps navigation system but didn't pre-download any maps. Once they lost cell coverage they lost the gps map (the gps still worked but there was no map on the screen). So not only did they not know where they were, the search teams couldn't locate them by using the phone because the did not have a cell signal. Here's an article explaining it better........http://www.time.com/time/business/article/0,8599,1735091,00.html

Edited December 14, 2012 by theexbrit

[silverton]

It's a limitation of the software then, not the hardware.

[Precise1]

I think he's saying that the most GPS are one way receivers, cell phones are a different animal due to being transmitters and that it's not a valid comparison. This is his area of expertise from what I understand and what he says makes sense. Ok, maybe there are web sites and services available to track a non transmitting GPS, I don't know about that, but I'd do a lot of research and experimentation before trusting it to be my lo-jack. Saying it's software not hardware doesn't really make sense in this comparison of apples and oranges.

 

B

[silverton]

I think he's saying that the most GPS are one way receivers, cell phones are a different animal due to being transmitters and that it's not a valid comparison. This is his area of expertise from what I understand and what he says makes sense. Ok, maybe there are web sites and services available to track a non transmitting GPS, I don't know about that, but I'd do a lot of research and experimentation before trusting it to be my lo-jack. Saying it's software not hardware doesn't really make sense in this comparison of apples and oranges.

 

B

 

I'm saying it's a software limitation because when I had an HTC Sense phone, I could use the HTC website to track my phone, when I wasn't running the factory Sense software, I could no longer track it.

 

And I don't understand how it's different, sure there is a cell radio in a cell phone and that's how it talks to the cell towers, but the gps is a different chip inside the phone altogether, just like when you have a laptop with built in GPS, it's the same stuff, just in a smaller package.

[theexbrit]

I thought the article I posted in the link explained it better than me but I'll try.... Most GPS "navigation" devices are just built to receive a signal from the satellites (the satellites are broadcasting their own location in space), these devices receive a signal from several different satellites & compute their location internally within the GPS unit using triangulation of the satellites signals. The satellites are in a stationary (geosynchronous) orbit around the earth & do not move from their set location in relation to the earth. The info from the satellites signal is used by the GPS receiver to triangulate it's position, the cell phone chip uses the cell towers to do the same. Once the phone is out of cell coverage the phone chip will have no idea where it is, but the GPS chip will unless it is masked from the satellites signal, then you're screwed! :laugh: So if you're in the Mont Blanc tunnel neither the phone or the GPS will work.

 

The satellites have no idea where the GPS device is as the GPS device is not transmitting it's location, there is no need for the extra expense of adding a transmitter that would be needed for fitting a transmitter, as it is not required for the GPS device to know where it is & navigate (which is all the device is designed to do). Adding a transmitter would also dramatically reduce battery life. There are devices such as "Spot" or Trackstick" that are purely transmitters & can not help you navigate as they do not have a receiver & therefore do not know where they are, only the satellites know where the device is (because it is transmitting a signal that the satellites use to triangulate the device position) & send out the location via a signal to a ground station on earth. The satellites can then be accessed by the appropriate device (software & hardware) to show where the device is located (LoJack, etc). So basically, it all comes do to which device wants to know where it is or which device wants the satellites to know where it is (receive & transmit). There are some devices that will do both, but these are expensive & not a $200 Garmin GPS.

 

The reason that you couldn't use a non HTC program to track your phone was that the non OEM software wasn't setup to "talk" to the satellites ground station (companies want you to buy their own software & are very protective of their frequencies & software). Don't believe the sheee-ite you see in movies where someone hacks into the satellite system & knows where Shia LaBouf is at any given time It's possible I suppose but you'd have to be a friggin' good hacker.

 

Hope that helps clear this up as my arse is getting sore from sitting on my uncomfortable chair typing this!!

Edited December 16, 2012 by theexbrit

[silverton]

So essentially, The HTC Sense software was turning on the GPS to get the location, then transmitting that over the cell network? That makes sense. Wonder if it still works if some thief uses their own SIM.. probably as long as the would-be thief has a data connection.

 

Just always thought GPS was a two way thing.

Edited December 16, 2012 by silverton

[theexbrit]

So essentially, The HTC Sense software was turning on the GPS to get the location, then transmitting that over the cell network? That makes sense. Wonder if it still works if some thief uses their own SIM.. probably as long as the would-be thief has a data connection.

 

Just always thought GPS was a two way thing.

 

The phone can use the GPS chip or the phone usually triangulates from the cell towers when there is cell reception, they say it's faster.

 

I wish it were a 2 way thing as I'd like my wife to know where I am when I'm out in the desert so she would know where to send the SAR helicopters when I don't show up at the house in the evening!!! :laugh: To do that now I'd have to go buy one of those "Spot" transmitters & still use my Garmin for navigation.

[RedPath88]

I've set up a couple of cell's for tracking in the past, of those most used the GPS chip (if equipped) to get location and then transmits that info back to a website over a cell network (because the typical GPS device only receives), where you can then retrieve the location, usually on a map to make it easier for the human brain to comprehend.

 

My current phone uses the GPS chip as a primary and then tries to supplement that info with Cell signal and local wifi information to try and increase accuracy. But the primary is still the GPS and keep in mind that this is one of the higher-end current phones.

 

As for HTC phone's GPS not working after Sense was removed, it was probably due to the carrier's GPS chip access being integrated into Sense. Now this does not apply to all older or maybe even current phones because the carriers often lock out the GPS chip from use by anything but ther own paid service offerings. If the chip is not locked out then there are a number of programs that do this now, two of which I recommend based on my own experience with them. For families Life360 and for security/theft recovery (I recovered my stolen phone using this) Lookout But keep in mind that both of these, just like any other locating software for a cell phone, requires cell coverage to report its location.

Edited December 17, 2012 by RedPath88
Clearified the post

[silverton]

The GPS still worked, just being able to track the phone through HTC's service did not.

[RedPath88]

Then HTC's service was tied to Sence in one way or another.

[silverton]

Then HTC's service was tied to Sence in one way or another.

 

Right, I'm not arguing that. I just initially thought that GPS was a two way thing. Sense just has a built in service that grabs location on the phone via GPS and transfers that data over the cell connection to the built in HTC tracking service. without the HTC Sense software, it doesn't know the server to transmit the location data to.

[theexbrit]

You are correct sir!!

 

Strangely, as long as there is a cell signal most cell phones will actually use the cell towers before using the GPS to triangulate their position, they say it's faster but I don't see that really.

[silverton]

You are correct sir!!

 

Strangely, as long as there is a cell signal most cell phones will actually use the cell towers before using the GPS to triangulate their position, they say it's faster but I don't see that really.

 

Depends on if you're actually within range of at least three cell towers! I have a GPS lock on my Galaxy S3 in less than five seconds.

[theexbrit]

My GPS also locks in pretty quick on my phone so I don't know why they say it's faster

Edited December 19, 2012 by theexbrit