Abstract: Centralized monitoring and control of urban streetlights is achieved through wireless transmission and computers. The streetlight control devices, i.e., monitoring terminals, together with the monitoring center located in the streetlight management agency, form a two-level distributed computer control system. Communication between the monitoring center and each monitoring terminal host uses General Packet Radio Service (GPRS), while data exchange between the monitoring terminal host and each monitoring terminal slave uses power line carrier communication technology. Keywords: monitoring center; monitoring terminal; General Packet Radio Service (GPRS); power line carrier Abstract: This system performs monitoring and control of city street lamps via wireless transmission and computer. The street control apparatus is the monitor and control terminal. Together with the monitor and control center in the control agency, they form a two-stage distributed computer control system. The communication mode between the monitor and control center and each terminal mainframe is General Packet Radio Service (GPRS). The communication technology of power line carrier is adopted between the monitor and control terminal mainframe and each inferior frame to realize data exchange. Keywords: monitor and control center, monitor and control terminal, general packet radio service, power line carrier 1 Introduction Street lighting is an integral part of urban infrastructure, playing a crucial and irreplaceable role in urban traffic safety, public security, people's lives, and the city's appearance. It also signifies the strength and maturity of a city. Since the founding of the People's Republic of my country, urban street lighting has achieved remarkable results alongside the rapid modernization of cities, becoming a thriving public utility. However, the generally tight municipal budgets have created a significant contradiction with the increased installation of streetlights. In some open coastal cities, many streetlights, after installation, have faced financial pressures and the inability to afford the heavy electricity costs, forcing the shutdown of nearly half of the lights. As a result, some newly installed streetlights in recent years have become mere decorations, leading to a form of waste. How can we make streetlights shine, make cities shine, and make them shine more scientifically, saving electricity and money? This requires not only high-level lighting design and high-quality lighting equipment, but also a safe, reliable, and flexible control system. This system should be able to develop various control schemes based on different usage environments, functions, and lighting needs, creating diverse lighting effects through the organic combination of these schemes. Furthermore, when implementing a control scheme, it is essential to accurately monitor the operating status of each light fixture. Only by truly achieving these points can we guarantee good lighting effects. The development of modern computer-based centralized control technology provides an effective way to solve these problems. The urban street light monitoring and management system based on wireless communication is an effective and inevitable product of modern computer technology applied to urban municipal construction, realizing centralized computer monitoring, control, and management of urban street light systems. 2. System Composition The urban street light monitoring and management system based on wireless communication consists of a monitoring center, several monitoring terminal hosts, several monitoring terminal slaves, and communication equipment. The monitoring center is the hub for the operation, maintenance, processing, statistics, analysis, and supervision of the entire street light monitoring system, and is responsible for interconnection with other management networks. The monitoring terminals are responsible for the power supply and control of the street lights. The communication between the monitoring center and the monitoring terminals uses the GPRS public communication network. Telemetry, remote signaling, and remote control are performed. When an alarm occurs, SMS messages are sent to the on-duty personnel for timely fault handling. At each monitoring terminal, a GPRS terminal is configured on the standard serial port of each data acquisition device and the monitoring terminal host (located within a transformer) for data exchange with the center. The monitoring terminal hosts and monitoring terminal slaves (located within a road section control box) are connected by power lines, using power line carrier communication technology for data exchange. The system block diagram is shown in Figure 1. [align=center]Figure 1 Block Diagram of Urban Street Light Monitoring and Management System Based on Wireless Communication[/align] 3 System Working Principle The urban street light monitoring and management system based on wireless communication uses wireless transmission and computers to centrally monitor and control discrete controlled objects. In the computer monitoring and management system, the street light control devices, i.e., the monitoring terminals, and the monitoring center located in the street light management agency form a two-level distributed computer control system (the upper-level computer is located in the monitoring center room, and the lower-level computers are located in each monitoring terminal). The upper-level computer in the monitoring center also serves as the management computer and engineer's workstation, mainly performing functions such as remote control, telemetry, remote signaling, fault analysis, data retrieval, system maintenance, electronic display, and report printing. The lower-level computers in the monitoring terminals are real-time online controllers, continuously detecting line status, parameters, and querying commands from the monitoring center to complete functions such as street light switch control, current, voltage, power and power factor detection, and voltage regulation and reduction operation. The communication between the monitoring center and each monitoring terminal host uses General Packet Radio Service (GPRS), and the data exchange between the monitoring terminal host and each monitoring terminal slave uses power line carrier communication technology. 4. Main Functions of the System 4.1 Main Functions of the Monitoring Center ① Monitoring Content: Monitor transformer phase voltage, phase current, operating temperature, and humidity; monitor line switch status, active power, fault alarms, and power consumption. ② Control Content: Perform unified switching control of the entire line (line control); perform independent control of individual lamps (point control). ③ Remote Control Methods: Control the switching of streetlights according to changes in illuminance (light control); control the switching of streetlights according to a predetermined schedule (time control); the monitoring center can manually control the switching of streetlights, combining light control, time control, and manual intervention. ④ Management Functions: Complete system configuration by changing system configuration files; perform network settings; manage local or remote workstations (computers or laptops). ⑤ Alarm Function: When the monitoring terminal actively alarms or the dispatch terminal detects an alarm via telemetry, the dispatch terminal should automatically report the relevant fault parameters via voice. For unattended situations, an electronic duty function should be provided to promptly notify relevant personnel via SMS or Email. ⑥ Schedule Function: Sets automatic timed schedules, temporary schedules, full-night light schedules, and half-night light schedules. ⑦ Calculation Function: Automatically estimates the lighting rate based on changes in voltage, current, active power, and power factor. To ensure accurate lighting rate statistics, data acquisition accuracy should be better than 1%. ⑧ Geographic Information Function: Utilizes a Geographic Information System (GIS) development platform to organically combine lighting monitoring and geographic information management. The map can be zoomed and displayed in layers; the overall view shows the geographical location of the entire system, while detailed information for a specific control point can be displayed. Geographic information is the core of the interface, including geographic topographic information, installation locations of each road section and terminal equipment, parameters of various equipment, and a database of operational data. ⑨ Data Statistics and Reports: Statistically compiles various information from the system and its operation, generating reports for analysis and research targeting specific purposes. ⑩ Web Information Publishing and Remote Real-Time Inquiry: Employs Internet technology to publish various data from the system via the WWW, allowing users to view the operational status of each road section's lighting system through a web browser via the MIS network or dial-up network. ⑪ Telephone Voice Access: Through encrypted dial-up query, users can access the latest status and fault information of the current road segment monitoring system using a dual-tone multi-frequency (DTMF) phone (including mobile phones). ⑫ Security Management Function: For operational security, the system employs hierarchical access control. All important operations require strict personnel password and permission verification to prevent unauthorized operations, and detailed log records are maintained for post-event traceability. 4.2 Main Functions of the Monitoring Terminal: The monitoring terminal adopts optimized automatic calibration, automatic tracking, and AC sampling technology, enabling adjustment-free, maintenance-free, and calibration-free operation, ensuring long-term stability. ① Light Switch Control Function. ② Streetlight Operation Data Acquisition Function. The monitoring terminal mainly detects data such as current, voltage, power, power factor, electricity consumption, and contactor status. Data acquisition is divided into analog quantity acquisition, digital quantity acquisition, and switch quantity acquisition. Based on the acquired data and system settings, the operating status and fault conditions of the streetlights can be determined. ③ Intercom function: The monitoring terminal's data radio can be plugged into a microphone to communicate with the control center or street light maintenance vehicle. This allows street light maintenance personnel to communicate with each other anytime and anywhere, greatly facilitating their work. ④ Remote reset function: When the monitoring terminal malfunctions due to unexpected circumstances, it can receive a remote reset command from the control center, initialize the monitoring terminal program, and restart, improving system reliability. ⑤ Wireless data communication function: The monitoring terminal can return street light operating status data such as voltage, current, and power consumption to the control center periodically or randomly via a wireless data communication network. In addition, each monitoring terminal can act as a communication relay station, relaying data from monitoring terminals that are far away or located in high-rise buildings where communication may be difficult to maintain to the main station, thus ensuring uninterrupted communication without setting up a dedicated communication relay station. ⑥ Automatic fault reporting function: When serious faults such as power outages, daytime lights on, nighttime lights off, or cable theft are detected, an alarm is automatically sent to the control center, ensuring real-time fault response. ⑦ Output status display: The position status of each output relay and the input status of each telemetry signal are indicated by lights. ⑧ Display and button functions: Equipment operating status parameters can be displayed on-site, and operating parameters of the monitoring terminal can be entered on-site. The parameter list for the monitoring terminal is as follows: 5 Conclusion The urban street light monitoring and management system based on wireless communication is an inevitable result of the development of modern computer centralized control technology and wireless transmission technology, and is an inevitable direction for the development of urban street light management systems. This system involves the latest scientific research and technological achievements in multiple fields such as computer technology, communication technology, and automatic control technology, and is an important symbol of the level of urban modernization. Its adoption and promotion can not only improve the level of street light management and service quality, but also generate significant economic and social benefits in terms of energy conservation, environmental protection, and public safety. The innovation of this paper: Using General Packet Radio Service (GPRS) and power line carrier communication technology, and with the help of computers, centralized monitoring, control, and management of discrete street lights are implemented. The system has high scalability, strong resource sharing performance, and good economic and social benefits. 6 References [1] Shenzhen Greute Electronics Co., Ltd., Proposal for Centralized Monitoring System of Urban Lighting Night Scene and Road Street Lights. 2001, 11 [2] Guo Peng, Sun Wei. Development of Remote Wireless Monitoring System Based on Mobile Phone Short Message (SMS). Computer Measurement and Control. 2002, (8): 506-507 [3] Deng Xiaohua, Liu Guangming. Public Street Light Control System Based on Power Line Carrier and GPRS Communication. Journal of Nanchang Water Conservancy College. 2004, (3): 53-56 [4] Zhang Yusheng, He Hongtai. Overhead Power Line Monitoring System Based on GPRS Wireless Technology. 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