A cartoon explains what LED light visible communication is on the tall

WiFi technology has become more and more popular, but there are more and more people complaining about unstable wireless signals, slow Internet access, and too few WiFi hotspots. However, there is a new technology that can solve these problems by using a flash of light to wirelessly transmit digital information. This type of technology is often referred to as visible light communication (Li-Fi). This cartoon will tell you what it looks like on the tall Li-Fi in the most easy-to-understand explanation.

Use optical networks to spread the information that everyone sends to the world. Next, we will introduce the technology that can quickly transfer massive amounts of information at one time.

What is optical communication?

Optical communication is a technique that uses light to transmit information to the other party.

The basic structure of optical communication?

Computers and mobile phones around us send information via electrical signals "0 and 1". Optical communication is composed of a "transmitter" that converts an electrical signal into an optical signal, a "receiver" that converts an optical signal into an electrical signal, and a "fiber" that transmits light.

Advantages of optical communication

1) Long transmission distance, economical and energy saving

Assume that 10Gb of information (10 billion signals) is transmitted in one second. If electrical communication is used, the signal is adjusted every 100 meters. In contrast, if optical communication is used, the adjustment interval needs to be 100 kilometers or more. The fewer the number of adjustment signals, the less the number of machines used, and therefore the economical and energy-saving effect.

For example, when talking to a foreign friend or chatting online, it feels no different from talking in the country. Unlike the past, the sound will lag behind. In the era of only electrical communication, the distance that can be transmitted at one time is short and the amount of information transmitted is small, and international communication is mainly transmitted as a relay through artificial satellites. However, when optical communication is used, the one-time transmission distance is long and the amount of information transmitted is large. Therefore, by using the optical fiber cable laid on the seabed, it is possible to realize natural communication with overseas. (The speed of the electric wave and the light are the same. However, since the transmission path becomes longer via the satellite, the signal arrives slowly. The distance of the submarine cable is much shorter, so the signal will be reached faster.)

2) One-time transmission of massive information

A large number of users can receive the required information (movies or news, etc.) at the same time. In one second, electrical communication can only transmit up to 10Gb (10 billion 0 and 1 signals). In contrast, optical communication can transmit up to 1Tb (1 trillion 0 and 1 signals).

3) Fast communication speed

The communication will be delayed due to electrical noise, resulting in a decrease in communication speed. However, optical communication is not affected by noise, so signals can be transmitted quickly.

Where is optical communication used?

Internet-based devices such as the Internet, mobile phones, and IP phones connect everyone to their region, to the entire country, and even to the global communications network. For example, signals from computers and mobile phones gather at the base stations and network providers of local communication carriers, and then transmitted to the world through optical fibers in submarine cables.

Various devices connected to the network

The various devices we use today are networked. The emergence of the Internet has made our lives more comfortable and convenient.