Nowadays, many offices or families will install WiFi to solve people's daily Internet problems. Wi Fi has a huge impact on the use of mobile computing, but it also has its disadvantages, such as small signal coverage, easy to be hijacked by hackers, and the increase in the number of users will become very slow.
Li fi, also known as visible light wireless communication, is a new wireless protocol, which uses visible spectrum to provide wireless network access. Li fi transmitters use LED lights to adjust the light intensity, mostly beyond the range of our eyes, and are read as data by the photosensitive receiver. Because LEDs already use chips to control their output, they can modulate up to millions of times per second, theoretically transmitting data 100 times faster than Wi Fi.
What is lifi
Although there may be many people who are not familiar with lifi, in fact, this is not a new technology just proposed recently. In a speech in 2011, Professor Harold Hass made many people realize that this is another technology that can change the world. As long as there is light, there is a high-speed network. It seems to be suspended, but in fact, the principle is not complicated.
Just adding microchips to ordinary LED bulbs can make the bulbs flash millions of times per second, in which the light on represents 1 and the light off represents 0, so binary data can be quickly encoded into light signals, and terminal devices (computers, mobile phones, tablets, etc.) under the light can receive signals to form a network through a set of special devices. Although this kind of light flickers millions of times per second, it is totally invisible to the naked eye. It looks like it's no different from ordinary light, so don't worry about being blinded.
According to the test results previously reported by foreign media, under ideal laboratory conditions, the transmission speed of lifi can reach an average of 100GB / s, and the theoretical peak value is about 224gb / s, which is nearly 100 times faster than the existing WiFi transmission speed.
In addition to cutting off WiFi in speed, lifi has many aspects that WiFi can't match
1. High density and low cost
LED lights are everywhere in our life. We can use the existing lighting lines to achieve optical communication. Moreover, the cost of LED lights transformation is much lower than the cost of deploying WiFi hotspot, let alone the cost of global base stations built to enhance data network signal (2g-5g).
2. Environmental protection without radiation
WiFi relies on invisible radio wave transmission. The higher the equipment power is, the higher the local electromagnetic radiation is, and electromagnetic interference will be generated at the same time. While lifi relies on the flicker frequency of light for data transmission, there is no problem of electromagnetic radiation and interference. Lifi is a better choice for hospitals or airplanes that are sensitive to electromagnetic signals.
3. Solve the frequency crisis
We all know that when the WiFi connected devices in your home exceed a certain range, your network speed will change. Because WiFi radio wave only accounts for a small part of the whole electromagnetic spectrum. With the continuous growth of users' demand for wireless network, the WiFi network will become crowded one day. It is understood that Professor Harold Hass has studied this Li fi technology since 2003, because he foresaw the coming spectrum crisis. The width of visible spectrum is 10000 times of WiFi, which can alleviate the current situation of global wireless spectrum resource shortage.
4. Prevent being scratched
Because the WiFi wireless signal can pass through the wall, there is the possibility of being scratched by the network, and the light characteristics determine that lifi cannot pass through the wall to transmit the signal, which means that it has strong security.