Design Of The Car Without The Key Entrance Guard System Based On The Rolling Code Technology

With the progress of society and technology,entrance guard system is developing toward the intelligent direction,entrance guard system is to ensure that the property is the first element of security,the security of the entrance guard system has is a hotspot of attention and research.At present all kinds of entrance guard system has been developing rapidly at home and abroad,both in price,safety or reliability have a big difference,for average users,high safety of entrance guard system the price is too high,and before the fixed code encryption entrance guard system safety can't reach,so to design a low price,high safety and reliability of entrance guard system has very important practical significance.At present,with the increase of car theft,electronic technology is widely used in the automobile anti-theft device,in order to improve the safety of the car entrance guard system,reduce the number of car theft,this paper designs a car without a key entrance guard system based on the technology of rolling code.Keeloq rolling code technology is a kind of nonlinear,more change,resistance to intercept encryption technology,the sending code every time is the only and do not repeat,make it harder for the illegal crime to scan and deciphered,so as to ensure its safety,overcome the shortcomings of traditional fixed code encryption.In this paper,aiming at the shortcomings of the Keeloq algorithm still made for its improvement,in the part of hopping code for the third time encryption,through the paper decodes the experiment,found that the bits above seven percent on changed,so that further enhance the security of the system,the radio frequency identification technology(RFID)used in this system,makes the transponder module and vehicle can more safe,rapid communication between station module.This article also carried on the detailed instructions to the system's hardware and software,the hardware part includes: car base station side hardware circuit design,high frequency receiving circuit,the low frequency transmitting circuit,transponder end hardware circuit design,low frequency receiving circuit,high frequency transmission circuit,such as the low frequency awakens the circuit design;Software part includes: the transponder main program design,the design of the key procedures,low frequency data receiving program design,vehicle station programming,study the design of the module.Finally,the system security are verified,the result shows that this design of the car without the key entrance guard system in safety,power consumption and cost,etc,in accordance with the system design.