A remote keyless system (RKS), also known as remote keyless entry (RKE) or remote central locking, is an electronic lock that controls access to a building or vehicle by using an electronic remote control (activated by a handheld device or automatically by proximity). RKS largely and quickly superseded keyless entry, a budding technology that restrictively bound locking and unlocking functions to vehicle-mounted keypads. Widely used in automobiles, an RKS performs the functions of a standard car key without physical contact. When within a few yards of the car, pressing a button on the remote can lock or unlock the doors, and may perform other functions. A remote keyless system can include both remote keyless entry (RKE), which unlocks the doors, and remote keyless ignition (RKI), which starts the engine. Numerous manufacturers have offered entry systems that use door- or pillar-mounted keypad entry systems; touchless passive entry / smart key systems that allow a key to remain pocketed; and PAAK (Phone as a Key) systems.
History Remote keyless entry was patented in 1981 by Paul Lipschutz, who worked for Nieman (a supplier of security components to the car industry) and had developed a number of automotive security devices. His electrically actuated lock system could be controlled by using a handheld fob to stream infrared data. Patented in 1981 after successful submission in 1979, it worked using a "coded pulse signal generator and battery-powered infra-red radiation emitter." In some geographic areas, the system is called a PLIP system, or Plipper, after Lipschutz. Infrared technology was superseded in 1995 when a European frequency was standardised. The remote keyless systems using a handheld transmitter first appeared on the French made Renault Fuego in 1982, and as an option on several American Motors vehicles in 1983, including the Renault Alliance. The feature gained its first widespread availability in the U.S. on several General Motors vehicles in 1989.
Function
Keyless remotes contain a short-range radio transmitter, and must be within a certain range, usually 5–20 meters (16–66 ft), of the car to work. When a button is pushed, it sends a coded signal by radio waves to a receiver unit in the car, which locks or unlocks the door. In automotive implementations, the receiving element is typically integrated into the vehicle body structure as a dedicated automotive RKE receiver antenna. Most RKEs operate at a frequency of 315 MHz for North America-made cars and at 433.92 MHz for European, Japanese and Asian cars. Modern systems since the mid-1990s implement encryption as well as rotating entry codes to prevent car thieves from intercepting and spoofing the signal. Earlier systems used infrared instead of radio signals to unlock the vehicle, such as systems found on Mercedes-Benz, BMW and other manufacturers. The system signals locked or unlocked status through discreet signaling—by the lights, horn, or both. A vehicle might use a chirp system: two beeps on driver door unlocking, four beeps on unlocking of all doors, a long beep for the trunk or power tailgate or a short beep on locking and arming of the alarm. The functions of a remote keyless entry system are contained on a key fob or built into the ignition key handle itself. Buttons are dedicated to locking or unlocking the doors and opening the trunk or tailgate. On some minivans, the power sliding doors can be opened/closed remotely. Some cars will also close any open windows and roof when remotely locking the car. Some remote keyless fobs also feature a red panic button which activates the car alarm as a standard feature. Further adding to the convenience, some cars' engines with remote keyless ignition systems can be started by the push of a button on the key fob (useful in cold weather), and convertible tops can be raised and lowered from outside the vehicle while it's parked. On cars where the trunk release is electronically operated, it can be triggered to open by a button on the remote. Conventionally, the trunk springs open with the help of hydraulic struts or torsion springs, and thereafter must be lowered manually. Premium models, such as SUVs and estates with tailgates, may have a motorized assist that can both open and close the tailgate for easy access and remote operation. For offices, or residences, the system can also be coupled with the security system, garage door opener or remotely activated lighting devices.
Programming
Remote keyless entry fobs emit a radio frequency with a designated, distinct digital identity code. Inasmuch as "programming" fobs is a proprietary technical process, it is typically performed by the automobile manufacturer. In general, the procedure is to put the car computer in 'programming mode'. This usually entails engaging the power in the car several times while holding a button or lever. It may also include opening doors, or removing fuses. The procedure varies amongst various makes, models, and years. Once in 'programming mode' one or more of the fob buttons is depressed to send the digital identity code to the car's onboard computer. The computer saves the code and the car is then taken out of programming mode. As RKS fobs have become more prevalent in the automobile industry a secondary market of unprogrammed devices has sprung up. Some websites sell steps to program fobs for individual models of cars as well as accessory kits to remotely activate other car devices. On early (1998–2012) keyless entry remotes, the remotes can be individually programmed by the user, by pressing a button on the remote, and starting the vehicle. However, newer (2013+) keyless entry remotes require dealership or locksmith programming via a computer with special software . The Infrared keyless entry systems offered user programming, though radio frequency keyless entry systems mostly require dealer programming.
Passive systems
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