Today’s reader question comes from Deepak.
Here’s what he’d like to know:
I have heard that all GPS receivers also have a high frequency transmitter and the receiver body itself acts an antenna and the ID and location of the receiver are continuously being tracked by GPS master control station though the satellites.
No that is not true.
Very few “home” GPS receivers have transmitters. If you buy a car GPS or Outdoor GPS from Garmin or Magellen for example, it doesn’t have a transmitter…it would just cost too much and would be used for nothing.
Some examples of GPS devices that DO send location signals back:
- RENTAL Car GPS systems
- On Star equipped GPS systems
- Newer cellphones that have GPS directions MAY transmit your exact location.
The satellites could give a hoot about your location, or any other location of a GPS receiver. The systems that can track your location, like Onstar for example, get their location from satellites, then using an internal database, transmit this data to a specified location (Onstar control center)
About like your local FM radio station tracking every single one of the radios listening to it. The cost would be ungodly, not to mention completely pointless.
(Why do I always hear the Twilight Zone theme when I’m on these forums???)
No. The ones you buy that track your location are receivers… ONLY. There are other units used by companies with fleets of vehicles that send tracking information back to make sure that the vehicles are where they are supposed to be.