**Introduction**
Real-time detection of parking spaces plays a crucial role in achieving intelligent parking management and optimizing the utilization of parking areas. It is also an essential requirement for modernizing parking systems. The evolution of parking space detection systems has generally gone through three stages: ground loop detection, gate control, and real-time position sensing. The level of detection technology directly affects the performance of these systems. With the rapid development of sensor technology, the accuracy and reliability of detection have significantly improved. However, traditional systems often suffer from large physical structures, complex installation processes, and limitations in terms of reliability, real-time response, scalability, energy efficiency, and ease of deployment—making them unsuitable for the fast-growing demands of modern parking environments.
WiFi, a short-range wireless communication technology, uses radio waves to connect devices and is widely used in indoor wireless LANs. Its main advantages include wide coverage (up to 100 meters), high transmission speed (up to 54 Mbps), and low entry barriers, as any device supporting WiFi can join the network with proper permissions. In parking space detection systems, WiFi is used to transmit data from sensor nodes, eliminating the need for cumbersome wiring and reducing both cost and power consumption. It also enhances system scalability, making it more flexible for future expansion.
Radio Frequency Identification (RFID) is a non-contact automatic identification technology that uses radio frequency signals. Operating at the 2.4 GHz band, RFID reduces the hardware requirements of the system and minimizes sensitivity to frequency deviations. Integrating RFID into parking detection systems helps standardize equipment and improves vehicle tracking by uniquely identifying each vehicle. This allows for quick location of parked vehicles and better management of available spaces.
This paper presents a scalable AMR-based parking space detection system that integrates WiFi and RFID technologies. The proposed system significantly reduces costs, complexity, and energy consumption while improving detection accuracy and enabling easy scalability for future growth.
**1. System Design**
**1.1 Parking Space Detection System Design**
The parking space detection system consists of a server, a wireless router, a parking display, an RFID reader, and AMR (Anisotropic Magneto-Resistive) sensor nodes. The server handles data processing and sends results to the display screen. It also sends commands to the RFID reader. The wireless router connects all components into a local area network. The parking display shows real-time status of each parking spot. The RFID reader receives data from the AMR sensor nodes via WiFi and forwards commands from the server to the sensors. The AMR sensor node detects changes in the magnetic field caused by vehicles and transmits this information wirelessly to the RFID reader.
The system uses a star topology, where the RFID reader acts as the network controller, and the AMR sensor nodes function as slave nodes. This structure ensures efficient communication and centralized control.
**1.2 System Circuit Design**
The circuit design of the parking space detection system includes:
1. **AMR Sensor Node Circuit**: This includes the power supply section, magnetic field acquisition unit, data preprocessing module, and RF transceiver. The power supply is managed by the TI APL5312-33 chip, providing a stable 3.3 V output from a 4.2 V input.
2. **RFID Reader Circuit**: This includes the RF transceiver, WiFi module, data processing unit, and control section. The RFID reader communicates with the AMR sensor nodes using the SPI interface and manages data flow across the network.
The AMR sensor node utilizes the MMC2122MG magnetoresistive sensor, which offers high sensitivity, low power consumption, and stability. It supports two-axis magnetic field detection and integrates an I2C bus, allowing direct connection to a microcontroller without requiring an ADC. The MSP430F2618 microcontroller is used for data preprocessing and communication with the CC2500 RF chip, which transmits the processed data to the RFID reader.
The RFID reader’s RF transceiver employs the CC2500 chip, which communicates with the control unit via SPI. The CC2591 enhances signal strength and receiver sensitivity with low-noise amplifiers and power amplifiers, making it ideal for high-performance wireless applications. This design ensures reliable and efficient communication between the RFID reader and the AMR sensor nodes, forming a robust and scalable parking detection system.
Ware Resistance Lining Ceramics
Ware Resistance Lining Ceramics,Alumina Tile Plat,Ware Ceramic Liner,Alumina Tiles Plate
Yixing Guangming Special Ceramics Co.,Ltd , https://www.yxgmtc.com