LED lights become a breakthrough in indoor precise positioning technology

Since 2012, major technology giants have invested in the indoor positioning market. For example, Google's indoor map, Baidu's indoor positioning service for shopping malls, and Apple's iBeacon technology for indoor positioning have 90 hours in indoor, public places, special environments, offices, apart from being at home, accurate indoor positioning will definitely change people's life, social intercourse, shopping, entertainment and other ways. However, most of the existing indoor positioning technologies use wireless signal strength such as Bluetooth and WiFi to estimate the distance so as to realize positioning. However, they all have the following defects: many signal access points ( For example, Baidu indoor positioning uses WiFi signal access point, while Apple ibeacon uses Bluetooth signal access point) This undoubtedly increases the cost and complexity of indoor positioning technology. Second, due to the instability of wireless signal propagation, its intensity changes constantly at the same position, so it is difficult to estimate the accurate distance and improve the positioning accuracy. At present, the accuracy of indoor positioning is generally less than, that is to say, positioning cannot reach a counter or a shelf indoors, which greatly limits the application scenarios of indoor positioning. An LED lamp on the top of the head has become a breakthrough in the bottleneck of indoor positioning technology. This technology, also known as visible light communication technology, uses high-speed light and dark flicker signals that are invisible to the naked eye, such as light-emitting diodes, to transmit information. First, give each lamp an address in the room, compile this address into a modulation signal, the pulse width modulation method is used to attach this signal to the driving current of the LED lamp so that each LED lamp can emit this address through the light. When the user receives this address, it can be associated with the position of the lamp to achieve positioning. Light is transmitted in the air along a straight line, and its intensity decreases evenly with the transmission distance. If a positioned person can be illuminated by a beam of light on the top of his head, then he must be under this beam of light, therefore, the positioning accuracy can be within 1 meter. Moreover, there are a large number of light sources indoors, especially in parking lots and large commercial buildings, where lights are open 24 hours a day, this provides a large number of existing infrastructure for indoor positioning based on visible light, greatly reducing the cost of foundation laying. Once the light source is laid, it will not change in a short time, which greatly reduces the maintenance cost of this technology for indoor positioning. Based on the technical advantages of UBeacon system, Huace Optical Communication Technology Co. , Ltd. has developed UBeacon system, which is also a system with practical application value at present. UBeacon system includes LED light source, user's mobile phone and mobile phone positioning and navigation application software. It first solves the Hardware Adaptation problem. UBeacon system directly uses the user's smart phone as the optical signal receiving end. The user only needs to install an application software on the phone without adding any hardware. And considering from the cost level, the existing visible light indoor positioning system is mainly spent on hardware facilities. Since the UBeacon system does not require too much hardware, the hardware cost is only a set of modulation modules installed in LED lamps, and there is no need for communication between LED lamps, so it can be laid according to ordinary lamps, no increase in installation costs. Of course, compared with other existing indoor positioning technologies, UBeacon system has the advantage of positioning accuracy of 1 meter and is not affected by any environment, not to mention it also has the characteristics of fast positioning speed and good positioning effect. In terms of pure technology, UBeacon system has not only changed lighting, but also triggered a revolution in the history of indoor positioning technology.