key fob

An automotive key fob is a compact electronic device designed to remotely control various vehicle functions, primarily unlocking and locking the doors, as well as activating the vehicle’s alarm system. Key fobs enhance convenience and security by eliminating the need for a physical key to access or start the vehicle.

The key fob comprises a microcontroller, radio frequency (RF) transmitter and receiver, battery, and buttons for specific functions. When a button is pressed, the microcontroller processes the input and sends a coded signal to the RF transmitter. The transmitter then modulates the signal into a specific frequency and transmits it wirelessly to the vehicle’s receiver.

The vehicle’s receiver, tuned to the same frequency, decodes the received signal and verifies its authenticity. If the signal matches an authorized code stored within the vehicle’s security system, it triggers the intended action, such as unlocking the doors. Additionally, key fobs often incorporate rolling code technology, where the transmitted code changes each time the key fob is used. This prevents unauthorized interception and replication of the signal.

Key fobs also feature a battery that supplies power to the microcontroller, transmitter, and any additional functions such as remote start or trunk release. To ensure consistent operation, key fob batteries require periodic replacement.

Leave a Reply

Your email address will not be published. Required fields are marked *