At this stage, the functions realized by the smart street light system are still relatively simple, and they are not combined with the development of the Internet of Things. The design concept is still at the level of energy saving, and the degree of intelligence is low. With the development of network technology, the interconnection of all things must be realized, and the smart street light system will be an indispensable part of modern cities. There are also some high requirements for the hardware modules of the current smart street lights.
1. Light sensor module
The optical sensor adopts photoresistor to realize simple optical detection. Mainly detect the on and off status of street lights, and measure the fault detection of LEDs.
2. GPRS communication module
TC35i is a new generation of GSM wireless communication module launched by Siemens. The module can be controlled by at command set, supports PDU mode and SMS. In addition, the module also has functions such as roaming, multi-party calling, and address book. There are power saving mode, idle mode, call mode, etc. As the core of the TC35i, the baseband processor mainly processes the voice signal and data signal in the module, including all analog and digital signals in the cellular radio equipment.
3. Doppler microwave module
Using the radar detection of the Doppler microwave module, by emitting a group of microwaves with a certain frequency, when the object or human body moves, the reflected microwaves will change its frequency. The frequency increases as the object gets closer to the source of the emission. Conversely, when the target principle is the transmitting source, the frequency is reduced. The reflected microwave frequency is detected by the microwave detection module to determine whether there is a human body or a vehicle passing by. The magnitude of the frequency has a linear relationship with the moving speed of the object, so the moving speed of the object can be reflected by the changing law of the frequency.
4. Power module
Since the voltages of the LED lamp drive circuit and control circuit are 24 volts and 3.3 volts respectively, and the ordinary mains electricity is 220 volts, the street lamps are installed in the control light box, and the voltage needs to be converted and lowered during use to provide each chip and module for use .
5. Function realization
Through the analysis of the current road conditions and the analysis of the surrounding conditions, the system is controlled in real time. Through the information collection and analysis of various sensors, the actual usage is judged, the street lights are automatically turned on, and the street lights are automatically turned off when there is no one or no car, and the lights are controlled according to the environment. When the ambient light is lower than the set threshold, the system will automatically turn on the street light, truly realizing the automatic control of the street light.
