Locked keys in truck
After several months of caring for my dying MIL, I was able to take my youngest daughter and both granddaughters out camping for the first time this summer. We pulled into the campground about 8pm a...
Forum Discussion
for several years I helped design equipment for the test systems for phones and towers used for the two cell phone systems in use in the US today, GSM, (ATT etc.) and CDMA (verizon, sprint etc).
Both systems
a) operate on frequencies FAR away from the frequencies used for car remotes
b) both systems transmit digital encrypted digital signals that require decription keys for any meaniful data stream
c) CDMA signals look and are virtually background noise. Even very sophisticated test systems only see noise unless the transmitted and recieved signals have the correct digital key. It is probably the most sequre digital RF transmission system available in the world today.
d) for a car to recieve a signal in the frequency band it is tuned to recieve the cell phone signal would need to be mixed with another carrier frequency such that either the sum or difference of the two frequencies is in the remote carrier AND then the correct digital bit stream for the car reciever. And the key fob somehow would need to cause the audio signal recieved by the cell phone from the fob to be the RF digital bit stream from the remote.
So..... is it possible? Well, this is a case where only a "negative proof" is possible. Even though I can't see any way it would happen but can't prove it isn't possible. The only proof would be to see it happen (negative proof) to show it DID happen.
So.... IMHO don't expect this trick to get you out of a jam.
Both systems
a) operate on frequencies FAR away from the frequencies used for car remotes
b) both systems transmit digital encrypted digital signals that require decription keys for any meaniful data stream
c) CDMA signals look and are virtually background noise. Even very sophisticated test systems only see noise unless the transmitted and recieved signals have the correct digital key. It is probably the most sequre digital RF transmission system available in the world today.
d) for a car to recieve a signal in the frequency band it is tuned to recieve the cell phone signal would need to be mixed with another carrier frequency such that either the sum or difference of the two frequencies is in the remote carrier AND then the correct digital bit stream for the car reciever. And the key fob somehow would need to cause the audio signal recieved by the cell phone from the fob to be the RF digital bit stream from the remote.
So..... is it possible? Well, this is a case where only a "negative proof" is possible. Even though I can't see any way it would happen but can't prove it isn't possible. The only proof would be to see it happen (negative proof) to show it DID happen.
So.... IMHO don't expect this trick to get you out of a jam.
