In the nautical era of Columbus, the world suddenly became very big; after the advent of computers and the Internet, the world began to shrink again. With the increasing popularity of Internet technology applications, the human lifestyle has begun to change. Earth people seem to become "wisdom" overnight, and even items have "thoughts."
Not only that, in the future of rapid development of technology in 2050, no matter which kind of equipment is used, data can be transmitted by wireless means at any time and anywhere. The popularity of LED optical wireless networks promotes the development of the "Internet of Things", and the whole world is easily connected...
Today, people are used to wireless Internet access. Without the restraint of the network cable, we can enjoy the fun of surfing the Internet. However, because the object is blocked like a wall, some places in the room will inevitably receive no signal, or the signal is extremely weak. So, scientists imagine, why not let the lights emit signals? As long as the light is on, you will not be online.
This seemingly empty idea is now a reality. In the China Aviation Museum of the Shanghai World Expo, scientists from the Institute of Semiconductors of the Chinese Academy of Sciences presented the latest and most avant-garde results: LED optical wireless network...
According to the optical cable network principle light as a medium "flashing" signal
The LED light is switched on and off at a very fast frequency, and the light is pulsed when it is flashing to achieve signal transmission. This high-frequency flicker is undetectable by the human eye, so the LED light can be illuminated and signaled.
On the LED optical wireless network display platform of the aviation museum, a beam of light straight into a laptop, the staff freely surfing the Internet under the light. This is the LED optical wireless network - the transmission of light from LED lights as a network signal transmission tool.
The principle is that the LED lamp does not stop switching at a very fast frequency, and the light emits a pulse when the light is blinking, thereby realizing signal transmission. This high-frequency flicker is undetectable by the human eye, so the LED light can be illuminated and signaled.
Since the late 1970s, researchers have studied indoor optical communications. Engineers at the IBM Zurich laboratory built their first working system at the time. In everyday life, examples of transmitting data by light are also found everywhere. For example, the infrared transmission function on mobile phones in earlier years.
Nowadays, when energy-saving LEDs become the trend of future lighting, scientists naturally choose it as a tool for transmitting signals. Moreover, the LED light is visible light, which is more convenient for people to "press the cable".
According to the cable network, the performance mirror reflection can also access the Internet. When the diffuse light makes the whole room bright, the network signal will fill the room. Even more amazing is that the light reflected through the mirror also has the same signal!
The coverage of traditional wireless networks is highly dependent on the capabilities of wireless routers. When used, a wireless router transmits a radio frequency signal, that is, a radio wave having a certain transmission frequency. Although this type of radio wave has not been proven to be harmful to the human body, it is not environmentally friendly after all. In contrast, the biggest advantage of optical transmission signals is that there is no electromagnetic wave.
The signal strength of an optical wireless network lies in the light intensity, on the one hand, and the sensitivity of the receiving detector. At the current level of research in China, it is possible to achieve diffuse reflection reception—when the diffuse light brightens the entire room, the network signal then fills the room. Even more amazing is that the light reflected through the mirror also has the same signal!
LED optical wireless network does not have any requirements for network operators and computer equipment, as long as it is an ordinary external network. LED lights currently on the market are only illuminated. If you want to use it for communication, you must install a small "instrument" on the LED to enable high-frequency flicker.
In the past, a region had to achieve full coverage of wireless signals, and only a large number of wireless routers could be placed. Nowadays, scientists can directly carry communication signals in the place where the community wires are connected. At that time, whether it is the street lights of the community or the lighting of each house, the Internet signal can be sent.
According to the optical cable network, the advantage is faster than the optical fiber. The optical wireless network on the aircraft just targets the "last few meters" problem, that is, how to transmit the broadband data stream from the information backbone terminal to the indoor wireless device. it goes without saying.
LEDs transmit faster and the signal is more stable. The difference in LED materials can result in different modulation capabilities and maximum bandwidth. At present, internationally, LED optical wireless networks can theoretically reach a rate of 500 Mbps.
The communication company also has a "last mile" argument, referring to the dilemma of accessing broadband services from the nation's high-speed data communication backbone to end users: although this is only the last small segment of the entire communication path, The high cost is staggering. The fiber broadband into the cell is now 100M. In fact, fiber-optic communication is still light, but it is transmitted in a special fiber, and the external interference is small, so the speed is fast. However, different cells need to build different fiber networks, which usually takes a very long time.
Similarly, the optical wireless network is just for the "last few meters" problem, that is, how to transfer the broadband data stream from the information backbone terminal to the indoor wireless device, the advantages are self-evident.
Such optical wireless networks are particularly well-suited for use in hospitals and factories because traditional radio frequency transmissions can interfere with navigation devices, medical devices or control systems in these areas.
In addition, the LED optical wireless network allows people to use broadband at will on the aircraft. The aircraft is connected to the ground in real time via satellite and is thus connected to the Internet. When the LED light "lights" the network signal to each passenger, there is no electromagnetic wave interference, and the aircraft navigation is completely unaffected.
In the future, the application of this technology allows the car to communicate with the front and rear lights. But it's just a voice communication, and you have to rely on street lights to get online.
"LED Optical Wireless Network" 2050 Feasibility Report Optical wireless network is very commercial and easy to use, but it is also difficult to implement because it chooses one of the most complicated channels - the atmosphere to transmit data. The sky full of unpredictable weather will definitely bring a lot of variables to wireless optical communication, but indoor use is certainly no problem.
A series of features of optical wireless communication: fast transmission speed, low cost compared with paving fiber, fast construction speed, no need for radio frequency permission, no municipal permission to excavate pipes, portability, easy maintenance, no surrounding environment influences.
However, optical wireless communication is limited by the amount of transmitted energy, and it is impossible to transmit too far, and reliability is also affected by many external factors. For example, an enemy creates a fire on the link of an optical wireless network, destroying information integrity with artificial smoke.
However, the above drawbacks obviously do not hinder the development of optical wireless networks. When LEDs become the inevitable trend in the future, LED optical wireless networks have become inevitable.
The Internet of Things (2050) Feasibility Report (The Internet of things) is defined as: through information recognition devices such as radio frequency identification (RFID), infrared sensors, global positioning systems, laser scanners, etc., according to the agreed agreement, A network that connects any item to the Internet for information exchange and communication for intelligent identification, location, tracking, monitoring, and management.
The Internet of Things has a very broad prospect that will dramatically change our current lifestyle. It can be said that the Internet of Things portrays a world full of intelligence. Specifically, the sensor is embedded and equipped into various objects such as power grids, railways, bridges, tunnels, highways, buildings, water supply systems, dams, oil and gas pipelines, and then the "Internet of Things" is integrated with the existing Internet. To achieve the integration of human society and physical systems. On this basis, human beings can manage production and life in a more sophisticated and dynamic way to achieve a "smart" state.
LED optical wireless network: as long as the light is on, you can access the Internet
Keywords for the future city of 2050: digital life. This is a lifestyle based on the Internet and a series of digital technology applications, which can provide people with a better life experience and work convenience.