The LED bulb works so much that future WiFi will be replaced

Pacific computer network, since the invention of Edison, tungsten filament bulb has been serving people for more than a century, however, with the advent of the LED lights, its days are running out. The power consumption of a LED lamp is only 1/10 of that of an incandescent lamp, but the service life is 30 times as great as that of an incandescent lamp. Not only that, the use of LED lights is not limited to lighting, and with the invention of smart light bulbs, it has been given more additional features, it can make your laptop, smart phone connected to the internet. Put aside Wi-Fi, Li-Fi is here.

In fact, wireless communication with visible light is not a new idea. Everyone knows that on a desert island can be used smoke signals to attract attention; perhaps in the Napoleon era, few people know that Europe has been covering the optical telegraph, otherwise it would not call lights.

And by a wisp of smoke in the Morse code the way to partition, can form a distress message, visible light communication LI-Fi rapidly by adjusting the light intensity to the data compiled into binary 0 and 1. For example, "LED" means "1", "pass" means 0, and information can be transmitted by fast switching. However, this does not mean that the Li-Fi transceiver will blink because its speed is faster than the speed of the human eye.

Wi-Fi vs Li-Fi

With the enormous increase in the number of people using WiFi, a great deal of WiFi data transmission has brought enormous pressure to existing WiFI technology, which consists of radio and microwave frequency spectrum. With the exponential growth of mobile devices, by 2019, more than 10 billion devices are expected to be exchanged around 922 Jing, 3372 megabytes, 368 billion, and 54 million 775 thousand and 808 (10 of the 18 party) bytes of information. Due to frequency congestion and electromagnetic interference, the current WiFi technology will not be able to achieve the transmission of this data. The most prominent aspect of the problem is the urban areas, because the city has the largest number of WiFi users.

Basic communication principle is to carry on the biggest data transmission in the usable electromagnetic frequency band breadth. Radio frequency spectrum is widely used and managed, but there is not enough room to meet the increasing demand of users. So Li-Hi is likely to replace radio and microwave frequencies Wi-Fi.

For communications, visible light spectra are large, unused, and unregulated. The light produced by the diode can be modulated very quickly: using a single blue LED, the data rate is as high as 3.5 Gb/s. You can also reach 1.7Gb/s by white light.

Unlike Wi-Fi transmitters, optical communications are performed in confined rooms. This limitation seems to be the limitation of Li-Fi, but its key advantage is that it is very safe: no one outside the room can eavesdrop after the curtain is hung. The array of light sources on the ceiling can send different signals to different users. Transmitter power can be localized and can be used more effectively and will not affect the adjacent Li-Fi source. Compared with Wi-Fi, no radio frequency interference is indeed a big advantage. Visible light communication is very safe and allows travelers not to switch their equipment to flight mode.

The further advantage of Li-Fi is that it can use existing power lines, such as LED lighting, so there is no need to build new infrastructure.

Help reduce the burden of things

The Internet of things is a bold vision in a world where the Internet is highly interconnected and everything can communicate with the object itself. For example, your refrigerator will notify you when the milk is drunk or when it is out of date. The sensor of the car tells you when the tire is over worn or when the tire pressure is too low.

Because of the "stuff" in the Internet of things, sensors and controllers are needed for network connectivity, so the bandwidth required for these devices to communicate is enormous. According to forecasts, by 2020, 25 billion of these devices will be connected, and in fact, most of these things only need a short distance connection, so Li-Fi will become a realistic solution.

Some companies have begun to provide visible light communications products. Li-1st, based in PureLii, Edinburgh, offers secure, 11.5Mbps enabled wireless peer to peer access - equivalent to the first generation of Wi-Fi plug and play solutions. The other is Oledcomm from France, which uses Li-Fi to connect with hospitals.

Although there are still a lot of technical challenges, the first step towards Li-Fi is now being made. To be sure, your lights will open more in the future, not just lighting.

For more LED related information, please click on China LED network or pay attention to WeChat public account (cnledw2013).