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As long as you do n’t take up my frequency band, you can play whatever you want!

Yes, the frequency band resources were already heavily occupied at that time, and no one wanted to release the frequency band in their hands.

Finally, the FCC can only release three unwelcome “junk bands” from the only free bands. These frequency bands are the ISM frequency bands that we often mention now.

These frequency bands are mainly open to the three fields of industry, science, and medicine. They belong to the Free License (free license) , so they are also called “Unlicensed Spectrum”.

In terms of device transmission power, the FCC stipulates that the transmission power of these newly-licensed bands can reach 1W.

No one thought of it. This 1W is what makes today’s WiFi, Bluetooth, ZigBee and other short-range communication technologies.

At that time, in order to avoid interference between devices, the FCC required these new license-free products to use spread spectrum technology.

The so-called spread spectrum technology means that the bandwidth used to transmit information is much greater than the bandwidth of the information itself. Spread spectrum modulation is performed by spread spectrum coding at the transmitting end, and information is received by related demodulation technology at the receiving end. Spread spectrum technology was first used in the military field, and has the characteristics of high reliability, high confidentiality and less interference.

After the introduction of the new FCC regulations, it has been widely welcomed by the industry. However, just when everyone is immersed in development, new problems have emerged-

There is no uniform standard throughout the industry.

At that time, many wireless product equipment manufacturers developed their own dedicated equipment, and no one was a bird. The equipment between different manufacturers was simply not compatible.

In 1988, the US NCR company wanted to use unlicensed frequency bands to make wireless cash registers A company that was later acquired by AT & T) . So, they recruited Victor Hayes, an engineer in their R & D department, and asked him what to do about it.

Victor Hayes

Victor Hayes is very forward-looking. He believes that there must be a unified standard. Then, Victor Hayes teamed up with another engineer at Bell Labs, Bruce Tuch, to find the IEEE, hoping to establish a common set of unlicensed spectrum standards.

IEEE, Institute of Electrical and Electronics Engineers

So, in the early 1990s, IEEE established the famous 802.11 working group, with Victor Hayes as chairman.

At the same time, in 1991, NCR’s engineering team and its joint venture partner AT & T developed WaveLAN technology in Neuwegein, the Netherlands. This technology is considered to be the prototype of Wi-Fi.

So, is NCR the inventor of Wi-Fi? Not really.

While NCR was working on WaveLAN, the Australian government research institute CSIRO also invented a wireless network technology. The specific inventor is John O’Sullivan of the University of Sydney and his team.

Dr John O’Sullivan

In 1996, they successfully applied for a technology patent in the United States, the patent number is US Patent Number 5,487,069. (Later, a lawsuit was filed for this patent.)

In 1999, when the IEEE officially defined the 802.11 standard, the wireless network technology invented by CSIRO was selected and recognized as the best wireless network technology in the world, so it was adopted as the core technical standard of Wi-Fi.

Finally, the standard version of IEEE802.11: 802.11b (working in the 2.4GHz band) and 802.11a (Working in 5.8GHz band) , approved in December 1999 and January 2000 respectively.

While the working group is busy determining standards, Intersil, 3Com, Nokia, Aironet, Symbol, and Lucent have formed the Wireless Ethernet Road Compatibility Alliance (Wireless Ethernet Compatibility Alliance, abbreviated as WECA) .

The purpose of the establishment of WECA is mainly to carry out compatibility certification for products of different manufacturers, and to achieve interoperability between devices of different manufacturers.

After the establishment of the alliance, in order to facilitate market promotion, everyone plans to change a loud name, such as “WECA compatible”, “IEEE802.11b compatible” and so on. However, this sluggish terminology makes it hard for people to blurt out. For this matter, WECA also specifically consulted brand experts, who gave them many suggestions, such as “FlankSpeed”, “DragonFly” and so on.

In the end, the name “Wi-Fi” won.

It is called “Wi-Fi” because it sounds a bit like “HiFi”, which is easily reminiscent of CD players from different manufacturers that are compatible with any amplifier device. Later, some people said that “Wi-Fi” is the abbreviation of “wireless fidelity (Wireless Fidelity) “, which is actually just what people envisioned later.

In October 2002, WECA officially changed its name to Wi-Fi Alliance (Wi-Fi Alliance) .

The technology has been standardized and the stage name is also available. What should I do now?

Hug your thighs.

No matter how good your technology is, someone should be willing to use it, and it must be supported by an equipment vendor.

So, Lucent in the Wi-Fi Alliance found Apple, hoping that their products would introduce Wi-Fi.

Apple is very proud, they told Lucent: If your wireless adapter price can drop below $ 100, we will design a Wi-Fi slot in the notebook.

Lucent agreed.

In July 1999, Apple introduced Wi-Fi for the first time in its new generation of iBook notebook computers, but it is not a standard configuration, just an option.

Jobs demonstrated iBook G3 ’s “wireless” magic, he named it “AirPort”

However, it is this “optional” that quickly attracted other computer manufacturers to follow suit.

Not only have hardware manufacturers followed up on Wi-Fi, but Microsoft ’s Windows XP operating system has also added support for Wi-Fi (users do not need to install third-party drivers Or software, you can achieve wireless connection) .

Since then, the use of Wi-Fi has continued to expand, from individuals to families, from families to public places, and into the lives of each of us.

At this time, the IEEE802.11 working group readjusted the IEEE802.11 protocol standard and introduced a new physical layer standard IEEE802.11g. It uses a more advanced spread-spectrum technology called orthogonal frequency division multiplexing (OFDM) modulation technology, and its rate can be in the 2.4GHz band Reached 54Mbps.

Later, there were 802.11n, 802.11ac, and 802.11ad.

Development Track of 802.11

Because naming methods such as 802.11a / b / n / g / ac / ax are really confusing and it is not easy to see the order, IEEE decided to start with 802.11ax and name them numerically .

And 802.11ax is Wi-Fi 6 that we can’t catch on now.

After more than 20 years of development, the transmission speed of Wi-Fi 6 is 873 times that of the first generation Wi-Fi.

I have to say that Wi-Fi is a very successful wireless communication technology, it has changed us to a great extentlife.

Now, Wi-Fi is at the crossroads of history. Faced with the challenges of 5G, where will it go? Let time tell us the answer.

References:

https://mp.weixin.qq.com/s/Mq5IkeE36qnjMMJmNUFOiw

http://biz.zol.com.cn/638/6382835.html

https://www.zhihu.com/question/23539623/answer/109747299

http://xinwen.eastday.com/a/180310182443182.html