RFID Smart transportation application solution for recognizing license plates

With the expansion of city size and the improvement of people's living standards, there are more and more vehicles on the road. This not only increases traffic pressure, but also puts forward higher requirements for vehicle management. Is there any new technology to solve these problems? The answer is of course, it is smart electronic license plates.

When it comes to smart electronic license plates, many people will be curious. Here we will give you a popular science about what smart electronic license plates are and their future development trends. At present, the most common method of locating and identifying license plates basically relies on image recognition. After detecting the license plate number, it is compared with the list in the database. However, image recognition is greatly affected by environmental factors, and recognition of license plates is prone to errors. Moreover, when collecting images Blind areas often occur, and these uncontrollable factors limit the further development of image recognition.

In order to solve this series of problems, smart electronic license plates came into being. Smart electronic license plates are based on RFID technology. As an emerging non-contact automatic identification technology, RFID technology is different from traditional video and image processing license plate recognition technology. In comparison, vehicle identification based on RFID technology has high accuracy, is not easily affected by the environment, has no blind spots, and can accurately and comprehensively obtain vehicle status information and road network traffic conditions. The future development trend will be that electronic license plate recognition gradually replaces traditional license plate recognition methods.

The core of electronic license plates is electronic tags based on RFID technology, and RFID electronic tags are divided into two categories: active and passive. The advantages and disadvantages of the two tags are shown in Table 1.

Considering the service life and usage scenarios of electronic license plates, passive electronic tags have the characteristics of long life, small size, easy installation, and low cost, making them more suitable for vehicle installation and use. In terms of communication distance selection, ultra-high frequency UHF 860MHz~960MHz passive RFID tags have the advantages of long communication distance and fast transmission rate. They are a very good choice for electronic license plate recognition.

Since electronic license plate recognition has such a broad prospect, it must have many incomparable advantages and characteristics compared to traditional image recognition technology. Where are the specific basic requirements and technical advantages? We will simply list a few as follows:

Basic requirements for electronic license plates:

Can Store data (vehicle model, color, owner information);

The identification tag can be read from a long distance, and the distance of the fixed reading device is more than 10 meters;

High reliability, with a reading success rate of over 99.99%;

Can identify a large number of tags at the same time, up to more than 200 per second;

Accurately identify tags in high-speed motion, and the mobile recognition speed can reach more than 100km/h.

Technical advantages of electronic license plates:

Data encryption, a unique algorithm is used in the tag communication process, and it cannot be read by third-party devices;

Easy to install, no special installation Tools or materials required;

Unique person card and garage grouping matching algorithm can accurately determine illegally used motor vehicles;

All-weather, can work reliably in any weather conditions.

Precisely because electronic license plates have so many advantages and features compared to traditional license plates, it is foreseeable that in the near future, motor vehicles will gradually use electronic license plates with electronic labels to replace the current traditional license plates. In this way, from the front end of the vehicle From the electronic license plate to the back-end license plate recognition, data transmission, vehicle management, data storage, terminal query, etc., the construction and development prospects of the entire platform are very broad. Figure 2 is a schematic diagram of the entire platform architecture.

After talking about the principles and advantages of electronic license plates, some "old drivers" may start to wonder, are electronic license plates really practical? What are the specific applications? Next, let's briefly talk about the application scenarios of electronic license plates.

Scenario 1: Smart parking system

Speaking of most current parking lot management, many "veteran drivers" may have encountered problems such as difficulty in parking, high fees, and lack of parking spaces. In order to solve these parking problems, in recent years, national policies have clearly proposed to vigorously promote the application of high-tech technologies such as smart parking systems and automatic license plate recognition. To put it simply, the "wisdom" of smart parking is reflected in: intelligently finding a parking space + automatically paying parking fees.

So, how to implement smart parking currently? Let’s take the most common parking lot as an example. The most important technologies are license plate recognition technology and non-stop electronic toll collection (ETC) technology. Before a vehicle equipped with an electronic license plate enters the parking lot, the smart parking system can accurately identify the vehicle's identity from a long distance through the electronic license plate recognition device, record the vehicle's entry and exit time for accurate charging, and allow the vehicle to pass quickly without stopping for manual recording. When the vehicle exits the parking lot after parking, the smart parking system will conduct short-range communication with the electronic license plate through the license plate recognition antenna, and automatically complete the entire charging process without the need for the driver to stop or other toll collectors to take any action.

The application of smart parking systems can improve passing efficiency and prevent the occurrence of traffic "bottlenecks" at toll stations. At the same time, RFID technology can be used to realize toll collection without human intervention, effectively curbing parking fee evasion, toll collectors' negligence of duty, and malpractice for personal gain. , while reducing the management costs of toll stations and recovering infrastructure investment faster.

Scenario 2: Intelligent traffic management system

RFID technology can be used as an effective means of information collection in traffic dispatching systems and can be applied in traffic dispatching management systems. For example, applying RFID to the bus park management system can realize the automatic, accurate, long-distance, and non-stop collection of information when buses equipped with electronic license plates enter and exit the bus station, allowing the bus dispatching system to accurately grasp the real-time dynamics of buses entering and exiting the bus parking lot. information. Through the implementation of this system, the management level of buses can be effectively improved. By using computers to conduct research and analysis on the collected data, we can grasp the vehicle usage rules, eliminate loopholes in vehicle management, realize intelligent management of bus vehicles, and enhance the image of the city.

In addition, the use of RFID as a technical means is highly economical. Compared with technologies such as Global Positioning System (GPS), it has the characteristics of easy installation, strong adaptability, low cost, and no need to modify the vehicle. At the same time, special dispatch and management can also be carried out for special service vehicles such as garbage transport vehicles and dangerous goods transport vehicles. Through the electronic license plate installed on the vehicle, identification equipment is placed at the monitoring point on a specific road section to monitor whether the vehicle is traveling on the prescribed route. When emergencies such as leakage occur, the location of the accident vehicle can be located in time.

Through the introduction of the above two practical application scenarios, we have a more intuitive and clear understanding of electronic license plates. Figure 5 is an example diagram of the application of electronic license plates in specific industries. From this we can see that the key to the application of electronic license plates , inseparable from reading and writing devices and data transmission. The IoT7000A-LI network controller launched by Zhiyuan Electronics uses the Cortex-A7 core i.MX6UL multimedia application processor as the core, with a main frequency of 528MHz, dual 100M Ethernet, and onboard dual MiniPCIE interface design, which can be expanded to GPRS/3G/ Wireless communication modules such as 4G, ZigBee, LoRa, WiFi, GPS/Beidou, etc. build a bridge between LAN and WAN. With the license plate recognition antenna, it can easily realize the reading and transmission functions of license plate data, and can operate at -40℃~+ It operates stably within a temperature range of 85°C and meets various harsh industrial applications. It is a must-have for building smart transportation systems.

In the future, with the advancement of science and technology, from smart wear to smart travel, future smart cities will be closer and closer to us, and people's travel will become more convenient. Let us look forward to the wonderful things that technological innovation will bring us. In the future.