PCB Blog - Radar security system application

At present, security system is an important security system in all fields, and its fundamental role is to prevent accidents. Therefore, in-depth research and development of security technology has become increasingly concerned. Millimeter wave radar has become one of the emerging security equipment, which has powerful functions in the presence sensing, tracking and speed measurement of targets.

Millimeter wave radar has not been used for a long time in the field of security. The basic principle is that the transmitter transmits electromagnetic waves in combination with the radar antenna. If encountering obstacles on the transmission track, it will reflect, and the reflected electromagnetic waves will reach the receiver, so as to determine the actual position of the obstacles.

Intelligent millimeter wave radar induction module, integrated radar transceiver, IF circuit, MCU processing, etc., peripheral antennas and a small number of peripheral circuits constitute a complete radar sensor, which can be embedded in lamps, household appliances and various electronic products, and can realize the induction detection of human bodies, cars and other moving objects. Based on the Doppler effect, the radar module can flexibly adjust the sensing range. It adopts mature CMOS technology, single chip integration, high cost performance, self calibration function, and is free from external interference. The camera video of many traditional security equipment is vulnerable to environmental interference to generate false positives, or cannot operate around the clock. The millimeter wave radar has a strong anti-interference ability, and can operate 24 hours without interruption, and the wavelength is relatively small. It also has a penetrating function for wallboards, materials and clothing, with better detection effect and better directivity.

Millimeter wave radar has strong performance, rich algorithms and strong scalability, and is suitable for scenes with high performance requirements. It supports standard UART interface, and can be connected with other main control or sensors, and can also be used as the main control. With the continuous updating of technology, the chip integration of millimeter wave radar security equipment has been improved, the performance has become more powerful, and the cost has been reduced, which also makes it more popular in the security system. Security work is very important. When this kind of security system is actually used, security operators can divide the overall coverage area, such as early warning area, security area and threat area. When the early warning area enters suspicious people, the security system will give early warning. At the same time, the radar controls the drive of the intelligent camera to follow the intrusion target and determine its action track. The location information, specific track and moving speed of the target will be displayed in the management platform of the client, so that security personnel can make corresponding responses to avoid accidents or economic losses.

Smart FMCW scheme SOC radar, integrated digital lock loop, supports FMCW ranging, delimits the sensing area, interferes outside the shielding area, has low power consumption, low cost, and integrates high-performance 32-bit MCU. In addition to processing radar internal signals, MCU can also replace some upper computer systems. Dividing the security area and simply configuring it can promote the security work to be more orderly, the security efficiency of the system to be higher, and it is convenient for the staff to respond. Not only is it linked with the camera for shooting, but the radar can also guide the camera for tracking shooting of targets. The monitoring information shall be recorded and stored, and the history can be played back when necessary, giving play to the real value of radar tracking data. Alarm output provides API interface and secondary development.

The latest technology of millimeter wave radar security system in recent years is FMCW technology. Its principle is that the echo signal will be converted into a narrow and band difference signal form through mixing and amplification processing, and then sent to the processing module for signal processing. The purpose of processing is to retain useful signals and effectively eliminate useless interference. At the same time, the mixed frequency signal is processed after being amplified by IF, and the speed information and target distance information can be extracted through the signal spectrum. If it is necessary to identify multiple targets, the requirements for signal processing will be higher, and the algorithm used is very effective and fast, effectively identifying different targets. After adopting FMCW technology, the security monitoring system can achieve uninterrupted coverage monitoring throughout the whole process in the specified monitoring area. The reliability of this security monitoring system is relatively high. Compared with the traditional infrared system, it is light in weight, small in volume, relatively small in range blind area, and free of speed blind spot. It has high range resolution and can better resist external interference. In view of the problems faced in the development of radar technology and the potential development space, it is necessary to continuously improve and enhance radar technology, comprehensively and systematically improve the technical level and use efficiency of radar in combination with market demand and corresponding technologies, and promote the development of radar industry. In order to make the development direction of radar technology better adapt to the current industry demand, its radar information processing technology needs to be deeply reformed in the direction of intelligence and modularization, so as to improve the comprehensive use efficiency of radar and create more efficient use value.