GPS System as Car Locator

<div class='quotetop'>QUOTE(Marvinh @ Sep 16 2007, 10:39 AM) [snapback]513309[/snapback]</div>

Nah, the GPS system is a radio receiver, not a transmitter. It can't be used as a car locator anymore than your AM/FM radio can.

 

There is nothing in the car to transmit the GPS coordinates, even if it could, which it can't.

If you were an amateur radio operator you could install APRS, which would report the position of the car, but only if the car is in "ready". It would be unlikely any thief would go to the extreme measures required to get it to run (go to ready) when a flatbed truck is so much easier.

I don't understand why anyone wants to spend that kind of money protecting a $25,000 car. Don't the thieves go after more expensive or more demanded re parts vehicles such as Lexus, Mercedes, or Hondas first?

 

Hi Marvin,

I do not have a Prius with a GPS, but I know a little about LoJack. Its a digital 2-way radio system. The computer connected to the digital 2-way radio will respond to its ID being received with a locating transmission. I beleive there is a network of LoJack transmitters, kinda like a paging network, that can send these ID signals at the request of law-enforment. When the ID is received at the LoJack unit, its transmitter starts sending. The Police have RDF (Radio Direction Finding) equipment aboard specially equiped squad cars. These are the cars with 4 identical antennas in a square pattern on the roof. The police just follow the signal until they find the car. Having participated in Amateur Radio transmitter hunts, tracking a source from a moving vehicle is very easy with the psuedo rotating antenna technique that the LoJack tracking equipment uses. The various reflections get averaged out and a true bearing can be quickly determined. As one drives along one sees the bearing shift left and right of the true bearing as one drives past reflectors that cause a stronger signal at the antenna than the direct signal. Once one is close, the reflecting paths become weak compared to the direct bearing. So this gives one an approximate indication of range.

What you are suggesting is similar to the Amateur Radio APRS system. But you would need a NEMA GPS serial port on the Prius and a transmitter to send the data. This might be done using WiFi. A computer receives the GPS location by serial port or maybe even blue-tooth from the car. It then searches for open WIFI networks to do a broadcast packet back to a server. The server could then be accessed to get the time and date of the last location fix. APRS has a similar system, but the hubs use internet and shortwave backhaul. The equipment in the car is the typical amateur 2-way like FM transciever, with a connection between the microphone and the radio, that splices in the GPS data in coded synchoronous packet fashion.

The original APRS system was developed by a Ham who was also in charge of Navy Midshipmen doing their summer cruises. He hooked sent the GPS data through amateur data radio adapter equipment to the maritime frequency shortwave radio on-board the training vessels. With a broadcast data every few minutes or so, and he had a realtime map of the 10 to 20 training ship locations. By the way this ham - Bob - is a Prius owner and commonly posts on the Prius Technical Yahoo Group.

There is only a blue-tooth transmitter in some Prius. It does not have the protocol or range for long distance reporting. And the GPS data may not be linked to it either at this time. But that is probably just a matter of software. The NEMA port is built into GPS chip sets, and this is probably how the mapping computer gets the location. One might be able to splice onto NEMA serial port and copy the location reporting from the GPS chip set without interupting the data to the mapping computer. Then the added in computer with WIFI could send the GPS location over available WIFI networks. The advantage of WIFI is the computer and WIFI antenna could be readily conceiled. The disadvantage is that WIFI network that are free for usage do not have wide coverage. And many pay networks would block such data from being transmitted.

 

<div class='quotetop'>QUOTE(David Beale @ Sep 16 2007, 11:03 AM) [snapback]513318[/snapback]</div>

While Hondas do make the list (along with Toyota, Dodge, Nissan, Ford, Accura and Saturn), there don't seem to be any Lexus or Mercedes in the top 10 list released by the NICB in 2006 (I couldn't find a more recently list, but figured things probably haven't changed too much in the past couple of years.)


https://www.nicb.org/cps/rde/xchg/nicb/hs.xsl/72.htm

 

Many (most?) stolen cars are stolen for parts, so a popular model would be worth more to a thief than a model with a high sticker price. As the Prius becomes more popular and older, demand for parts will go up.

 

It will work if you combine it with the Trunk Monkey Theft Retrieval System, which can be seen in operation in this video.

Tom

 

Nuvi 700 might be right for you. It has "where is my car" function.

Review: http://www.gpsmagazine.com/2007/08/garmin_...he_precisel.php

 

The newest prius models have Safety connect which features stolen vehicle locator. It is an available package for gen 3 and 4. It uses GPS technology to locate a subscriber's vehicle just the way lojack or onstar would.

 

My $0.02 is that I got DataDots on my new Civic a couple years ago. It sounded kind of like a dealer gimmick, but we figured it really wasn't. They're incredibly small dot stickers that have unique codes in them. The dots are then placed everywhere around your car, so even if a thief found one, they would never find them all. It's a very similar idea to microchipping your pet. If you car is stolen and found by police somewhere, they can check out the datadots to see who the owner is. Here's some info about it.

DataDot > Brands > DataDot > The Leading Global Microdot Manufacturer

 

Two and a half years later...

What's the deal with the DataDots? My car came with them from the factory. How does one utilize them? Is there a subscription fee? I just noticed the (very difficult to remove) sticker advertising them on my window the other day.

 

best way to do this is get an iphone wire it up to 12volts put it in spare tire well and use find my iphone to find ur car! $25 a month on ur FRAMILY plan!
if my car is stolen i dont want to find it! let all-state find it or pay me for it!