A Design And Research Of Remote Keyless Entry System Based On KEELOQ

With the progress of science and technology, more and more household products are developing towards intelligent, bringing great convenience to people’s daily life. Smart home era has quietly come. As one of three major part of smart home, security and protection system is paid the most attentions. The access control system is the primary barrier to protect people’s personal and property safety. It has been a research focus with broad prospects for development. A wide range of access control systems, depending on the application areas, with different levels of security requirements. For the majority of the average home user, medium and high-end access control systems have high price, contact access control products and remote access system using fixed code have unsatisfactory security and reliability, therefore developing a secure, reliable, easy to use, low-cost access control system for average user has important practical significance.This paper designs and implements a remote keyless entry system(RKE) based on KEELOQ rolling code technology. KEELOQ rolling code is a data encryption technology designed specifically for the RKE system, it has been widely used in the automotive field, and its security is far better than traditional fixed code encoding.KEELOQ rolling code has an advantage of resistance to scan, anti-interception. This paper designs dual-model redundant system aiming at high reliability requirements of the intelligent access control system, and dual units work with the way of hotstandby. Host machine and backup machine make heart-beat mutual inspection periodically to monitor the other operational state. Once a fault occurs, the system automatically switches the operating module, it ensures the system could run continuously. In the software design, using C Language and Assembly Language program some key modules meanwhile. Compare C Language program with Assembly program in operating efficiency. There is a watchdog timer to prevent system paralysis caused by software failure which improves the reliability of the system further.The system uses KEELOQ rolling code technology as a data encryption means.First of all, this paper introduces rolling code technology in all its aspects, and then provides the overall design of the system, describes the working process of each module, achieves hardware design and the software program preparation. Finally,this paper gives the introduction of the system fault-tolerant design in hardware and software aspects, and verifies the dual-model system’s reliability by reliability evaluation model. The system runs well in many time tests, basically reaches the expected requirement.