Research And Design Of Passive Keyless Entry System

As the application of electronic technology on vehicle anti-theft devices, a variety of electronic anti-theft devices have emerged. However, vehicle theft continues to increase. The automobile manufacturers are competing to improve the anti-theft devices, to enhance its security, reliability. At present, with the radio technology development and utilization of computer technology in particular, vehicle anti-theft technology has been moving toward automation, intelligent development.The traditional automobile door control system are in-depth reseached and analyzed in the dissertation,and found that their safety is very low. Traditional remote control entry (RKE) system is a door control system of transmitting fixed-code one-way,and its security is provided by the code length to achieve, and can not deal with code scanning and recording ,or try all codes by professional staff.A hopping-code technology-based passive keyless entry system is designed in the dissertation. The key holder can open the door by gently touching the door. Hopping-code technology is an anti-interception, high-reliable technology. Its transmission code employs advanced nonlinear-bit encryption technology. The hopping-code sent by PKE system is unique, irregular, one-time effective, and can not be predicted, tracked, intercepted, cracked, so as to overcome the shortcomings of traditional door control system effectively.The hardware is designed and debugged in the dissertation, it mainly includes external LC resonant circuit, UHFDATA sender circuit, UHFDATA receiver circuit, 125KHz low frequency transmitter etc. The software of PKE system is also designed and debugged in the dissertation, and key technical issues of RF/LF communications and hopping-code encryption are solved. At end of the dissertation,the PKE system is tested entirely,the experimental results suggest that the system reachs design target in power consumption, communication distance and security.