Smart street lights have become the newest trend for lighting up the streets. As more and more projects about setting smart street lights are carried out, you may want to know how smart street lights work. Actually, the whole smart street light system consists of four procedures: perception, transmission, cloud computing, and control. These procedures proceed in order, resulting in the many functions of the smart street lights.
Perception
The perception part is composed of sensors, signal conditioning circuits, A/D converters, microprocessors, radio frequency communication modules, positioning modules, and power modules. Generally, the whole process goes through three parts: sensors, processors, and the wireless communication module.
The sensor module collects and converts information in the monitoring area. There are various types of sensors for smart street lights. For example, weather sensors, piezoelectric sensors, current sensors, and illumination sensors can collect different data.
The processor module is responsible for managing the entire sensor node as well as storing and processing data.
The wireless communication module is in charge of communicating wirelessly with other sensor nodes, exchanging control information, and sending and receiving data. The technology applied can include RFID, GIS, cameras, and remote sensing.
Transmission
There are many ways of transmission for smart street lights, which include NB-IoT, LoRa, optical fiber, network cable, wifi, zigbee, etc.
- Optical fiber communication: it supports docking, including pole-mounted WiFi AP, hand-in-hand ring networking, and other applications.
- Network cable: Gateways usually have Gigabit or 100M network ports, and some also support PoE power supply through the network port to achieve more functions.
- Power carrier: Broadband carrier communication technology allows for the collection of status data and centralized control via power supply connections.
- 4G/5G: Wireless communication functions can be a backup and supplement to wired connections and are appropriate for some suburbs and hilly places where installing lines is inconvenient.
- NB-IoT: This wireless communication technology provides a large number of connections, broad coverage, good penetration, low power consumption, and low cost, making it ideal for monitoring applications.
- LoRa: This is a new wireless communication technology that uses the spread spectrum to provide ultra-long-distance wireless transmission. Lora offers users a straightforward solution that achieves great range, extended battery life, and high capacity.
- ZigBee: ZigBee is a short-range, low-complexity, low-power, low-speed, and low-cost wireless communication technology. Its low power consumption and transmission rates make it ideal for short-distance data transmission between various electrical devices.
Through these means of transmission, the data collected by the sensors can be uploaded to the cloud.
Cloud computing
Cloud-based street lighting systems can be linked together via the Internet. The control terminal can perform remote monitoring and control through efficient data transmission. And then, by executing different codes, cloud computing can save energy, ensure security, and make management easier.
The smart street light system can save energy and protect the environment. It can automatically adjust the brightness and switching time of street lights based on varied weather conditions, light intensity, traffic situations, and so on. Cloud computing technology allows for real-time monitoring and management of current, voltage, and power. So the power of street lights can be modified at any moment to optimize street light energy usage.
Combining cloud computing with sensors can provide real-time traffic flow and heat map information. This will make it easier for municipal managers to modify the brightness and timing of street lights. Thus, ensure safe management of the traffic.
All street lights can be installed on the same cloud platform to achieve simultaneous control and improve management efficiency.
Control
The data is sent to the controller after it has been calculated in the cloud. The controller could be a smartphone or a PC. The manager sends instructions through the controller to regulate the street lights and monitor their status. When street lights fail, managers can receive notifications to schedule maintenance.
Conclusions
Through these four procedures, we can control the smart street lights in an easy way. In reality, the technique different systems choose may vary. No matter the sensors or the communication methods, there are many of them, and they have different benefits and costs. The smart street lights work to make it possible to save energy and achieve other amazing functions.
