This project belongs to the field of automotive electronics, involving key technologies such as automotive electronics, wireless communication and vehicle-mounted networks. With the rapid development of the automobile market, the continuous upgrading and application of technology, and the continuous improvement of people's living standards, automobiles have become one of the necessities of life and work. At the same time, people's requirements for the comfort and safety of automobiles are becoming increasingly high. Radio Frequency Identification (RFID) uses advanced vehicle identification and authentication technology, which has completely changed the development prospects of automobile safety and theft prevention applications and brought users a new and convenient driving experience. RFID is a wireless communication technology that can identify specific targets through radio signals and read and write related data without the need to establish a direct physical connection between the identification system and the specific target. One of the typical application representatives of RFID in the automotive industry is the automobile high-low frequency interactive identity authentication system, which brings users a new driving experience. In terms of vehicle anti-theft security, there is a complex two-way identity authentication process between the smart key and the car's high-low frequency interactive identity authentication system. The principle is that the low-frequency antenna emits low-frequency signals to detect the relative position between the smart key and the body base station in the vicinity of the car body. The body base station is responsible for verifying the identity of the smart key and deciding whether to open the door lock or start the vehicle engine. In order to avoid various shortcomings of the traditional remote control key system, the R & D team of Shanghai Keshida-Huayang Automobile Electric Co., Ltd. has realized the industrial application of high-low frequency interactive identity authentication technology in the field of car safety control after years of technical reserves and practical applications, and achieved a series of innovative results.

1. Identity authentication for high-low frequency two-way communication triggers the sensor integrated on the door handle, and the vehicle-mounted low-frequency antenna sends low-frequency signals to the smart key. After receiving the low-frequency signals, the 3D low-frequency antenna integrated in the smart key will authenticate the message. After the certification is passed, the magnetic field strength at the location will be calculated, and the ID, magnetic field strength and other signals of the smart key will be sent to the body base station in a high-frequency manner. After the body base station receives a high-frequency signal such as the smart key ID number and passes the authentication, it will send a Captcha to the smart key through the low-frequency signal. The smart key that receives the Captcha will encrypt the data of the Captcha through a specific jump code algorithm, and send the encryption result back to the body base station through the high-frequency signal. The body base station compares the encrypted data received with its own calculation results. If the two match, it realizes the unlocking/locking action of the vehicle. Similarly, the start-up process also uses this two-way communication authentication technology.

2. The smart key accurately positions the low-frequency antenna and sends a 125KHz low-frequency signal into the spherical space centered on the door handle. It is used to detect the relative position between the smart key and each low-frequency antenna, and the measured position of the smart key. The magnetic field strength is transmitted to the body base station, which determines the relative position of the smart key based on the magnetic field strength at the location of the smart key and determines whether to unlock/lock the door. When the user presses the start button, the smart key is also searched for through the low-frequency antenna. According to the field strength fed back by the smart key and when it is in the car, the body base station conducts anti-theft certification of the engine with the engine management unit and realizes subsequent operations to start the vehicle.

3. Safe, reliable and low-cost power management backup strategy The high-low frequency interactive identity authentication system replaces the traditional mechanical ignition lock. After the vehicle is successfully started, the power supply of the whole vehicle is managed and backed up by the high-low frequency interactive identity authentication system and the body system to avoid accidental flameout while the vehicle is driving.

This project has been authorized for 1 utility model patent technology, 2 software patent copyrights, and applied for 3 invention patent technologies at the same time. It is at the international advanced level and fills the gap in the domestic high-low frequency interactive identity authentication system. This technical achievement has been applied in Brilliance Zhonghua Junjie FRV, A2 and Great Wall Haval H6, H8 and other models. Over the past three years, the cumulative economic benefits have reached 190 million yuan.