| Can A Keyless Entry Remote Unlock Your Car Via Cell Phone? |
 |
 |
 |
| Written by Guest |
| Tuesday, 09 February 2010 14:13 |
|
THE MYTH: There are many people who say they are able to unlock their car with a keyless entry remote or "key fob" from well outside the remote's radius with the use of a cell phone. Supposedly, if you call someone with an extra keyless entry remote for your car all they have to do is press unlock and hold the remote right up to the phone. On the other end you need to hold your phone right up to the receiver and the car should unlock. Think of the possibilities! It would not matter how far you were from the other person because the signal would be carried and retransmitted by the cell phone towers. This would be great if it were true... The problem is that there are some basic principles of waves that make this impossible. You see, a keyless entry remote is transmitting with radio waves and a cell phone works with sound waves. The cell phone is not designed to carry radio waves and therefore has no mechanism of receiving them. The radio waves cannot just magically go into the cell phone and travel along the connection if there is hardware in place to deal with that type of wave. Why is the myth so widespread? My best guess is that when people go to test this theory they are not standing far enough away from the car. Many remotes may only describe an effective radius of say 400-500 feet but could feasibly work from well over almost half a mile in the right conditions. The right conditions would include no large barriers between the remote and the car, as well as a nice, clear day.
Also, it is possible that some remote entry systems would actually work. Without getting too technical, if the remote transmits a kind of wave that a cell phone could pick up, then it would be feasible. There is just one other factor that would need to be in line. A keyless entry remote will typically transmit in the range of 800 MHz and cell phones are in the 300 MHz range. These would have to somehow be much closer, say with a specialized remote. As you can see there are a few key factors that would have to be adjusted, but it is possible. |
