◎ Science and Technology Daily reporter Liu Yan
In the second phase of China's first popular science program in the field of communications, "Communication Letter", presented by Science and Technology Daily, the World 5G Conference and the Future Mobile Communication Forum, Dr. Xu Han, head of R&D in Qualcomm China, sorted out the evolution process of mobile communication technology from 1G to 5G for us, and pointed out that technological maturity and application explosion complement each other.
Mobile communication technology, which evolves forward with an intergenerational evolution every decade or so, has changed the way people communicate, and has also promoted changes in social life and even production methods.
As Dr. Xu Han said, in the era of 1G analog communication technology, although the expensive "big brother" has limited coverage and slow speed, the communication between people has since freed itself from the shackles of fixed telephone lines. In the 2G era, analog communication technology gives way to digital communication technology, and the signal coverage of mobile phones is wider, the call quality is better, and the communication price is lower.
Dr. Xu stressed that both generations of technology are characterized by voice communication. Since the beginning of the 3G era, everything has become different, real communication technology has begun to mature, data transmission has become a keyword, and the emergence and rapid popularization of smart phones have made 3G technology land.
It is also from this time that two things are worth remembering.
Since then, the 3GPP International Standards Organization has become an important link in the industry, promoting the unification and development of global mobile communication technology standards.
The CDMA technology that emerged in the 3G era is rarely talked about today, but its technological contribution still occupies an important historical position in the development and evolution of mobile communications to this day.
Although the application spawned by 3G technology seems to be relatively rudimentary today, when the interaction between technology and application develops to a certain stage, we find that the data transmission speed is not fast enough, the bandwidth is not enough, and 4G technology has appeared, which has spawned many explosive applications.
In the same way, when 4G can't meet the further demand for bandwidth, 5G comes. More critically, its technical characteristics have brought about a revolutionary change in the role of communication technology on society, and communication technology no longer only serves people, but also connects people and all things.
From 1G to 5G, mobile communication technology has come to this day, and technological maturity and application breakthroughs complement each other.
Dr. Xu Stressed that in general, technology precedes application. Just like when you experience the benefits of 3G, 3G has actually been commercially available for some time. That is, technology has spawned new applications, which in turn have pushed technology to the next level. The same goes for 5G.
Since the commercial use of 5G, among many technologies, people are particularly concerned about millimeter wave.
Mobile phones can receive signals because there are many electromagnetic wave signals in nature that we can't see or hear.
From sound to light, there is a large spectrum that we don't normally feel, and one of them belongs to millimeter waves.
The lower the frequency, the better the propagation performance. However, low-frequency spectrum has become a scarce resource in most countries, and there is not much spectrum that can be used for 5G. Therefore, people have set their sights on high-frequency spectrum with a wide range of selectable spectrum and many available spectrum resources.
Dr Xu said: "The introduction of millimeter wave has brought about a huge breakthrough in technology. Before 4G, the high-frequency spectrum was hardly utilized. As an important part of 5G, 5G millimeter wave and medium and low frequencies cooperate with each other and complement each other, which is the key to achieving the full vision and potential of 5G. ”
The biggest feature of millimeter wave is its large bandwidth and the resulting extremely high speed; another feature is that its frame structure is relatively short, so its latency is low. Therefore, any application that requires very large bandwidth and very low latency can be used as a technical tool.
There is no technology with only advantages and no disadvantages, the key is to be able to find a better application scenario. Millimeter waves are the same, which may not be the best choice for some applications, but may be the only option for others.
"As various technical challenges continue to emerge, researchers will use a variety of technologies to solve these challenges." Dr. Xu Said, "From 1G to 5G, we have been solving problems, and the challenges of commercialization of 5G millimeter wave technology will be gradually overcome. ”
Source: Science and Technology Daily
Editor: Zhang Shuang
Review: Julie
Final Judge: Liu Haiying