Study Of Automotive RKE/PKE System With Anti-jamming, Security Access And Smart Development

Automotive remote keyless entry system(RKE) and automotive passive keyless entry system(PKE) are currently the two main vehicle access systems. RKE system eliminates the mechanical key(find the key, insert the key into the key hole and lock/unlock). When people both hands take some carriages, one just need a simple push on the button to accomplish the lock/unlock(alarm/disarm) function which brings much convenience to people. While for the PKE system, it could further eliminates the push action, one just need to carry the fob in his pocket, and when he come near to the vehicle that belong to the fob, the PKE will automatically complete the identification recognition, when people make some movements such as pull the door handle etc. the PKE system will automatically complete the control that people want(lock/unlock, alarm/disarm) which could further provide people the convenience. At current stage, the RKE system has become the standard requirement for the vehicle, while the PKE system has been used on the luxury vehicle which could provide more high level choice.Since RKE system is an one-way communication system, its two main disadvantage are the poor anti-jamming performance and the weakness in the security level whose the RF signal could be easily eavesdrop. While PKE system’s function is somewhat simple(lock/unlock). Currently the anti-jamming countermeasure is still limited besides adding SAW filter, increasing the transmit power, increasing signal redundancy. The most effective way is using the frequency hopping technology, but this will highly increase the relatively cheap RKE/PKE system’s overall cost. Under the security level, the Keeloq algorithm is widely used in normal RKE/PKE system for encryption/decryption. The 1980 s DES standard unbalanced Feistel structure is used in the Keeloq algorithm which has been theoretically broken by the cryptanalysis and physical side channel attack. It needs to be improved to meet the more complicated environment day by day. As the vehicle IT times coming, the development of the function needs to be pay more focus on the fob display that could show the vehicle current status, and this will also be a RKE system’s development trend.There are three focus of this thesis which is on the anti-jamming performance, security level and smart development. For the anti-jamming performance, we put forward a simple software improvement to enhance the anti-jamming performance, while does not need to add additional hardware cost and maintain the same power consume. And further we use the Matlab/Simulink tools to simulate the results. Under the security level, this thesis introduces the Keeloq algorithm’s hardware and software design and how to use the Keeloq in the RKE/PKE system, and we descript the current RKE/PKE system’s attack method and compare the resources and time needed for different attack method. Finally we introduced the SPN structure AES algorithm usage on the RKE/PKE system which could highly improve the RKE/PKE system’s security level. Under the RKE/PKE system smart development, the thesis introduced the two-way RKE communication system, the system diagram and the chip available. We put forward two main parameters: distance to cover and the battery life as the crucial factor. And we theoretically analyze the distance calculation for both. Finally we tested the vehicle’s RKE distance and make a radar plot for the result.This thesis main work is as below:(A) Anti-jamming performance(1) Describe and analyze the current anti-jamming countermeasure.(2) Put forward a solution that using inserting BACW(Blank Alternative Code Word) to improve the anti-jamming performance.(3) Using Matlab/Simulink to simulate the system’s result and its feasibility.(B) Security level(1) Describe the current RKE/PKE system security access method, and mainly focus on the Keeloq algorithm software and hardware implementation.(2) Introduce the current RKE/PKE attack method, traditional attack and cryptanalysis attack and make a list for the time and resource consuming to complete a successful attack.(3) Make the use of the AES algorithm for the RKE/PKE system.(C) Smart development(1) For the smart RKE/PKE communication system hardware design, we put forward 2 main parameter: distance to cover and battery life and make out the theoretical calculation.(2) For the smart RKE/PKE communication system software design make the definition for frame structure and the software flow chart.(3) Make a distance test on the real vehicle and get the result in the distance improvement.