After the gradual popularization of LED energy-saving street lamps, the problems of low energy utilization and inconvenient monitoring of street lights in traditional urban lighting are gradually solved, saving a lot of manpower and material resources. However, how to improve the cost-effectiveness of energy-saving street lamp monitoring solutions will become the inevitable result of municipal construction. trend. Figure 1 Municipal energy-saving LED lights The intelligent street lamp can effectively adjust the brightness of the lamp according to the flow situation and weather conditions, and can monitor the state of the lamp body and improve the maintenance efficiency. Figure 2 adjusts the brightness according to the flow of people The advantage of the traditional power transmission module for street lamp transmission is that the power supply line can be directly multiplexed as a signal transmission line. However, due to the serious unqualified power quality interference in the country, the transmission effect is not ideal and the price is high, which needs to be optimized. From the aspects of “reducing the cost of terminal modulesâ€, “convenient wiring and easy maintenanceâ€, the municipal street lamp management adopts ZigBee short-distance networkable wireless transmission scheme is a good choice. Figure 3 Networking mode is multi-level transmission To further reduce costs, we must consider the "reduction of the number of routes", which requires the use of LoRa technology for long-distance transmission. Low-power and long-distance transmissions have always been one of the two options for wireless communication, until the original military LoRa low-power WAN technology (a type of Low Power Wide Area Network technology, LPWAN for short) was converted to commercial use. When the transmission power is constant, usually the larger the spreading factor is set, the higher the receiving sensitivity that the module can obtain, and the farther the communication distance will be, but at the same time, the communication rate will decrease. Figure 4 Flexible Adjustable Spreading Factor For the unrealized smart municipality and the already adopted power carrier and short-range wireless transmission scheme, it is necessary to realize the real-time control level simplification of several large-area street lamps in the city, and the cost is low, and it is necessary to satisfy both long-distance and low-power consumption. Demand, LoRa solution has two major advantages in this field: · Reduced routing, LoRa wireless spread spectrum technology, with -148dBm receiving sensitivity, has more than twice the communication distance and coverage area compared to traditional 470MHz transmission, greatly reducing the number of gateways and construction costs, as well as construction complexity, traditional networking The problem of a large number of routes and the need to carefully calculate the optimal placement point of the route within the transmission range is also solved; · Super anti-interference, street lamp power supply cables and complex urban road conditions with high buildings will have a strong interference effect on wireless communication. LoRa uses ISM band wireless communication technology, which combines digital spread spectrum, digital signal processing and forward error correction coding. To effectively ensure the wireless communication is stable and reliable and anti-interference ability; · Node scheme The LED street light intelligent management system node (node ​​includes: wireless transmission module, core control system, LED lamp body) wireless transmission part adopts LoRa wireless module such as ZM470SX-M / ZM433SX-M. Due to the particularity of the above application environments, ZLG Zhiyuan Electronics also provides customers with various antenna layout assistance services, providing customers with an effective guarantee for shortening the research and development cycle and improving the overall competitiveness of the products. Figure 5 Intelligent street light control logic based on LoRa technology · Gateway solution Industrial Internet field ZLG Zhiyuan Electronics has launched the intelligent wireless gateway Iot-3968, with ARM9 as the core, two-way MiniPCIE interface design, and a variety of optional wireless interface modules (using MiniPCIE interface design, including Wi-Fi, ZigBee , LoRa, GPRS/3G/4G, etc.), to facilitate customers to quickly build smart Internet of Things gateway products suitable for their own industry. Figure 6 IoT-3968 Smart Wireless Gateway Replaceable Atomizer,Atomizer Replacement Bottle,Replaceable Atomizer On Vape Pen,Replacement Atomizer Set Lensen Electronics Co., Ltd , https://www.lensenvape.com
