AES-based Automotive Keyless Entry System And Its Implementation

With the continuous development of the automotive and the growing of functional requirements of cars, PKE enters the automobile markets and quickly get in upper automobile's good graces, following the RKE System. PKE Design Technology is almost held in some foreign companies'hands, resulting in higher cost and lower flexibility of PKE Products. So, in the big emerging car market of China, just a little of upper cars could outfit PKE System. In this paper, we took a series research of PKE System, and designed a practical, secure PKE System, and put it into practice.The paper first analyzes the research situation and development of the PKE system, and describes the functional modules in detail. The functional modules include MCU logic control module, UHF(315MHz) transceiver module, Low-Frequency(125KHz) transmitter module and LF Wake-Up module. The Wake-Up module is used to accomplish the function of self-locking and self-lock-free without any operations. Then, the UHF transceiver modules get the function of remote search and remote locking or remote unlocking. At last, to design PKE better, we studied into the PKE key-technology:Binary keying modulation, Manchester encoding, AES encryption and Authentication protocol.We take MC9S08DZ32 and PIC16LF1828 as the primary control chips of PKE System. The transceiver front-end remote control system which is used to gain ultra-low-power and high-performance of data transmission, is designed by using CC1101 and CC1150 (low-power UHF transceiver of TI) and a few additional passive components. The functions of auto Wake-Up and LF communications are accomplished by LF transceiver, which is designed by AS3933, MC33151, IRF 7389 and related passive components.The primary work is data encryption and authentication protocol in system software design. After hardware design, the article analyzes the KEELOQ encryption technology of Microchip and the VKSP security protocols. Referred to the hardware and software feature of our PKE design, the article puts forward an improved authentication protocol, based on AES Encryption arithmetic and dynamic password. And last, the entire system software design is completed.Finally, the paper adjusts the parameters of the system, by simulating the UHF (315MHz) transceiver circuits and LF (125KHz) transceiver circuits using ADS. At the end of the paper, PCB layout and system implementation of PKE system is given.