Interpretation: how far away from the application of visible light communication?

The driver of the House hearing, lights, mobile phone will be able to have the power to call and the Internet, it sounds cool, but this advanced technology has been in the laboratory environment occurred. For ordinary people, how long the project out of the laboratory? How will our lives change?

Dr. Shen Guobin of Microsoft Asia Research Institute is doing "visible light communication". He did the first indoor positioning research, in 2012 began to study visible light communication, is how to determine the location of the indoor light source. Last year, his team won the second place in the global indoor positioning game IPSN.

How does light transmit information?

As early as in 2004, IEEE magazine on the paper explained through the light-emitting diode (ie, LED lamp) to provide wireless network connection method, the specific principle is this:

LED is a semiconductor chip, with the traditional filament is not the same, the chip can be particularly fast switch, such as the use of alternating current lamp is 60 Hz, the human eye can not identify the flashing lights. At the same time, there will be a square wave, the modulation can be transmitted information, and we usually use the telephone radio communication is the same.

At present, many universities around the world have related research projects, most of them in the laboratory. In 2012, the communications industry magazine IEEE has published a paper to allow visible light transmission rate of 96Mbps.

By the end of 2013, can let the light a lamp power is 1W LED of the Fudan University in Shanghai led the lab, 4 computer under the light of the Internet, the highest rate of up to 3.25Gbps, the average net rate reached 150Mbps.

Microsoft Research Asia is also doing research in this area. The laboratory will try to light and the transmission rate of equipment at peak limit is not the same, want to study this possibility in conventional electronic devices, and his team at Taobao bought cheap LCD panel, a solar panel, a few dollars and you can test circuit board.

At present, Shen Guobin's team studied how to use the reverse reflector (Retro-Reflector), in fact, is a mirror, the original light path back to the LED lamp, forming a communication between LED and electronic devices.

They have been able to do, in the light of 1 megabytes of switching frequency, from the light to the device's downstream speed reached 10kb/s, while the upstream speed from the reflective device to reach 0.5kb/s.

In the Microsoft Asia Research and development center, we see this experiment with cheaper components made of: do not need to charge the line, there is no Wi-Fi signal, only one block with a LCD screen, mirror and solar panels similar mobile phone sized device. Light up the LED bulb flashlight, the device will light up, and began to transfer data. The LED lamp has become an energy source and information source for an ordinary device.

Intelligent traffic sign, networking equipment without charging

Try to imagine, the lights of the roadside signs of such scenes, signs immediately to nearby vehicle navigator transmission Road, tell you arrive at the destination the most unobstructed road; the morning light, you can air detector will tell you that the outdoor air quality, temperature and humidity, and the tester display has been hanging in the bed, do not need to charge, also do not need to connect Wi-Fi or bluetooth.

Dr. Shen Guobin said that the smart sign, do not need to charge the networking equipment above may be what they think of the future of visible light communication. It sounds beautiful, but it is still in the theoretical stage.

"We first thought is to discuss and product department to see this is not possible in the big Microsoft product blueprint to go inside, whether we design, or our ideas, as long as they can accept, we will be very happy. "

But it is not easy to achieve these, it is necessary to introduce a good transformation of the LED lamps, but also the need to launch electronic products with reverse launchers to the market at the same time. For a company, it is from the technology to the product, the team needs to cooperate with too much.

How far is the distance between the research and the product?

In 1880, a Canadian inventor Alexander Bell found an interesting play: change by adjusting the beam, transmission of voice signal, can both wireless dialogue - this is the first wireless telephone, is the use of visible light communication.

Baer patent application for this invention, and even the power did not appear, he also believes that this phone does not have any practical value.

In fact, no matter what the scientific research projects, in a product to do business, the product sector is still dominant. The product department has some problems to be solved, according to the development of technology is very fast and can be used on the products, and no related products, will be transformed into basic research products is very difficult.

In this case, the task is to research these cool technology through the paper or the internal Demo product departments to understand, hope they do product plans in the next will consider this technology. Shen Guobin said so.

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