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Brief Introduction Of Key Fob

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What is a key fob?

A key fob is a small electronic device that gives access to physical objects such as cars and garages. In general, the term also refers to decorative items a person carries with their keys, like small trinkets or souvenirs. In the automotive industry, a key fob is a small device with buttons that unlock/lock the car’s doors.

Keyless entry systems mainly use key fobs for locking and unlocking doors. When a user pushes a button on a car’s key fob, a short-range radio transmitter in the fob sends a distinct coded signal to a receiver unit in the car. That as a result unlocks or locks the doors. In addition, some key fobs can also be used to open the drunk or to start the engine remotely.

A traditional key fob is an addition to the car key itself but the newer version of it has replaced the key altogether. This kind of fob is called a keyless fob. In addition to unlocking and locking the doors, a keyless fob is also used to start the engine.

car keys

How a key fob works

A key fob contains a short-range radio transmitter/radio frequency identification (RFID) chip and antenna. It uses radio frequencies to send a distinct coded signal to a receiver unit in the device.

This receiver also contains an RFID tag, which is some form of stored information. The reader's transmitter sends a signal to the fob, which then adjusts to the transmitter's frequency. The communication between the fob and the receiver device happens instantaneously when the user presses a button on the fob.

The RFID chip on the key fob is designed to transmit specific RFID tag information. This information always matches what the receiver device has been programmed to accept.

For example, a key fob programmed to work with a car will only lock or unlock that car, and no other key fob will work with that car. So, if the information from the receiver tag matches the information that the fob is requesting, the locking or unlocking function will be completed. If there is a mismatch, the function will not be performed.

RFID key fobs often can be programmed to transmit various commands. For example, automotive key fobs often have different functions assigned to different buttons; in addition to remote vehicle lock and unlock, these functions include the following:

  • starting the ignition
  • arming or disarming the security system
  • popping the latch on the trunk
  • controlling automatic windows

car keys

Start your car with your key fob

Keyless ignition systems are becoming more common, with 62 percent of cars sold last year having this feature, Edmunds reports. Should you choose to go keyless on your next model, your fob can serve as a way to start or stop your car as long as the fob is in the car with you and your foot is on the brake. Just make sure to never leave your key fob in your car. For more information about car key supply, kindly be sure to contact us!


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