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This article is from WeChat official account:Love Faner (ID: ifanr), author: Lee extraordinary, from the title figure: vision China

This year’s iPhone 12 has resumed its old days of picking up goods at a price increase. Last year, users who held money to wait and see because iPhone 11 did not have 5G, finally had a reason to change.

At the press conference, Apple also introduced 5G as the most important highlight. iPhone 12 supports almost all current 5G frequency bands, surpassing mainstream Android models, but only the US version supports millimeter wave frequency bands.

Some netizens wondered whether the National Bank version that does not support millimeter wave is a castrated version of iPhone 12?

The answer is no. This will not affect domestic users’ use of 5G on iPhone 12. The domestic 5G network does not support millimeter waves.

However, there are indeed differences in the 5G experience between the iPhone 12 that supports millimeter waves and the National Bank version that uses low-frequency sub-6GHz. Let’s talk about the topic of 5G millimeters today. This article tries to clarify a few questions:

• What is the difference between the 5G experience of the US version of iPhone 12 and the National Bank version?

• Who is the “true 5G” of millimeter wave and sub-6GHz?

• Is it related to millimeter wave that iPhone 12 consumes fast power in the 5G state?

• Why does the US 5G network use millimeter wave but China does not?

• Is the current 5G millimeter wave really unavailable?

• Will China use millimeter waves in the future?

1. What is the difference between the 5G millimeter wave exclusive to the US version of iPhone 12 and the Bank of China?

The millimeter wave exclusive to the US version of iPhone 12 and the sub-6GHz supported by the National Bank version are actually the two major branches of the current global 5G network frequency band.

As the name suggests, The frequency wavelength of millimeter waves is less than 10mm, and generally refers to the frequency band above 24 GHz. Sub-6 GHz is the network frequency band below 6 GHz, because the wavelength is centimeter level, it is also called “centimeter wave.”

The millimeter wave and the centimeter wave, the name seems to be the millimeter wave wins, just like the millimeter-level positioning in the navigation satellite is obviously more accurate than the centimeter-level positioning, then 5G millimeter wave is more powerful than sub-6GH?

Indeed, millimeter wave has the unmatched advantage of sub-6GHz, which can be reflected in the most intuitive network speed.

According to the measured data of the network speed measurement platform Ookla, the download speed of 5G millimeter wave terminals is 4 times that of the frequency band below 6GHz, with an average rate of 900 Mbps and a peak rate of more than 2Gbps.

At the press conference last month, Apple stated that the iPhone 12 can achieve a peak downlink rate of up to 4Gbps, which also refers to millimeter waves. At present, domestic 5G packages within 200 yuan can provide up to 60G of traffic, which can be used up in 2 minutes at this rate.

Of course this is the theoretical peak,It is generally not achieved in actual use. In SpeedSmart’s 5G network test on iPhone 12, Verizon iPhone 12 using millimeter wave 5G has significantly higher download and upload speeds than the iPhone 12 using sub-6GHz 5G.

Since the millimeter wave is so strong, is it more cost-effective to buy a US version of iPhone 12?

Don’t worry, although millimeter waves can easily crush sub-6GHz at network speeds, there is a fatal flaw. That is, the signal attenuation is large and the coverage area is small.

According to common sense in physics, the higher the frequency, the longer the wavelength, the shorter the transmission distance, and the weaker the penetration ability. For example, the signal attenuation in the 28GHz frequency band is 1600 times higher than that of 700MHz.

So5G mobile phones using millimeter waves may be blocked by anything. Trees, rain and fog can block most of the signal, and even the human body’s loss of millimeter waves can reach 11~28dB, which can reproduce the iPhone 4’s “Death Grip”, let alone going through a wall.

Although there have been many technical solutions to solve the problems of millimeter wave signal attenuation and blocking, the performance in commercial applications is still not ideal.

More complicated manufacturing processes bring higher costs. According to Guo Mingchi, the sub-6 and millimeter wave 5G components used in the iPhone 12 series cost US$75-85 and US$125-135, respectively.

In addition, the iPhone 12 has recently been exposed to consume electricity quickly in 5G mode, which is also related to the antenna design of 5G mobile phones.

5G mobile phones generally use Massive MIMO(large-scale multiple input multiple output) antenna technology to improve network transmission efficiency, compensate for signal attenuation, and millimeter waves It is even more inseparable from this technology for commercial use.

However, Massive MIMO technology reduces transmission power consumption at the expense of higher computational cost. Multiple antennas transmit at the same time.(more out) And receiving signal (multi-input) means higher power consumption, and naturally more power consumption.

To put it simply, millimeter wave is like a sprinter with strong explosive power but limited distance. On the other hand, sub-6GHz is a long-distance runner who runs slower but farther. Its own advantages are also the opponent’s disadvantages.

Although Qualcomm ridiculed that Huawei’s 5G does not support millimeter wave last year, it is not true 5G, but in fact this is just a propaganda method between the two sides on the 5G route dispute. The millimeter wave and sub-6GHz do not actually conflict. On the contrary, 5G services will be provided in a collaborative networking manner for a long time in the future.

2. Why does the US use millimeter waves, but China does not?

As mentioned earlier, the commercial use of 5G millimeter waves faces many problems. So why does the US deploy 5G networks based on millimeter waves? Don’t American operators know the defects of millimeter waves?

Actually U.S. operators don’t want to use the low-frequency sub-6GHz, but most of this frequency band has been used for military communications and defense communications. Even if it is to be freed up for commercial use, clearing the frequency band will not be possible for a while Finished.

In this context, operators can only bet on millimeter waves. Verizon, which provides 5G millimeter wave services for iPhone 12, is also the world’s first operator of commercial 5G services. As early as 2018, it provided 5G services in 4 cities in the United States and stated that “millimeter wave spectrum is the realization of 5G ultra-wideband The cornerstone of the network”.

It can be subject to 5G millimeter wave supporting technologies that are not yet fully mature, and the popularity of 5G in the United States is relatively slow. According to data from M-Science, a subsidiary of Wall Street investment bank Jefferies, as of mid-July 2020, the number of 5G users in the United States was 4.082 million, which is less than half of the number of 5G users in South Korea.

On a global scale, most operators have first adopted Sub-6G as a 5G networking solution. S&P Global Ratings (S&P Global Ratings) A report shows that as of September this year, it has been commercialized in 52 markets around the world Of the 113 operators in China, only 12% use the millimeter wave frequency band.

Obviously, before millimeter waves completely solve the problems of signal attenuation and coverage, sub-6GHz is an effective solution to allow 5G to cover a wider range in the short term.

In fact, the United States has also realized this problem and has begun to go back and deploy sub-6GHz 5G networks. Not long ago, the United States auctioned the 100MHz mid-band spectrum originally used for military purposes to operators, and plans to start commercial use in mid-2022.

The report “5G Ecosystem: Risks and Opportunities to the US Department of Defense” published by the Defense Innovation Committee of the US Department of Defense also pointed out:

Due to propagation and cost constraints, millimeter waves cannot be deployed on a large scale in the United States at this stage. Sub-6 GHz IF spectrum (in the range of 3 GHz and 4 GHz) will become the global WAN in the next few years. standard.

Fortunately for Chinese operators, my country has relatively abundant resources in the Sub-6 frequency band, and can allocate continuous test frequencies of 100 MHz or above to several major operations, while foreign operators mostly rely on auctions to obtain frequency bands. The price is often hundreds of millions.

For example, last year Deutsche Telekom spent nearly 2.2 billion Euros (approximately RMB 17.2 billion) in order to acquire 40MHz spectrum in the 2GHz band.

Although China does not have to rush to use millimeter waves because of frequency band resources, it is also actively researching and deploying millimeter waves. Because millimeter waves, which seem a bit tasteless, are the real future of 5G.

3. 5G without millimeter wave is indeed incomplete

In the video about 5G in which classmate He became famous at station B, he once said that speed is actually the most boring application of 5G.

Picture from: Tiger Sniff

Currently, our perception of 5G is mainly due to the fact that the network speed is faster, because 5G still lacks killer applications.

In fact, in the three major application scenarios of 5G, in addition to the enhanced mobile broadband (eMBB) to increase network speed, there are also massive machine communications (mMTC) and ultra-reliable low-latency communication (URLLC).

To realize the last two 5G application scenarios, millimeter waves are inseparable.

For example, the mass machine communication (mMTC) should make the device connection density reach 1 million units/km2, so that even in the crowded subway And in the gymnasium, everyone’s equipment can also surf the Internet smoothly. This requires the use of 5G millimeter wave technology with the advantages of large bandwidth, high instantaneous speed, and large system capacity.

Application scenarios that require extremely low latency, such as AR/VR, cloud games, and industrial robots, are also applicable. The air interface time slot length of the 5G millimeter wave system can be as small as 0.125ms, which is only a quarter of the current mainstream 5G low-frequency system .

Just like the Global Mobile Communications System Association(GSMA) mentioned in the “5G Millimeter Wave Technology White Paper” that 5G millimeter wave is the inevitable direction of the evolution of mobile communication technology. Millimeter waves can fully unleash the full potential of 5G.

The technology to improve 5G millimeter wave coverage is also becoming more mature. In addition to Massive MIMO mentioned earlier, beamforming technology is also a common solution.

The difference between traditional 4G base stations and beamforming 5G base stations is like a light bulb and a flashlight.

The signal from a 4G base station diverges in all directions like a light bulb, while beamforming can aim radio waves at a terminal that needs a mobile network, like a flashlight, illuminating the beam to the target and moving with the target. Can greatly increase the communication distance of millimeter wave.

In addition, millimeter wave can deploy a large number of small base stations, and reduce the communication distance to ensure high peak throughput, thereby increasing the coverage, which is lower than the cost of 5G medium and low frequency tower-sized macro base stations.

With the support of a series of technologies, the current millimeter wave can reach 1 to 2 kilometers in outdoor line-of-sight, while the non-line-of-sight coverage distance is between 100 and 200 meters.

September Qualcomm United LoveLixin and Casa Systems expanded the millimeter wave communication range to 3.8 kilometers, which is currently the longest millimeter wave transmission distance.

Xu Hao, head of R&D in China of Qualcomm, once said that the millimeter wave capability is a complete 5G, and the deployment of 5G millimeter wave is an important step to realize the entire vision of 5G.

The above-mentioned technologies have brought the 5G that truly changed our lives closer.

When will China use 5G millimeter waves?

Although China’s 5G network was officially commercialized in June last year, according to the data of the Ministry of Industry and Information Technology, as of the end of September, the cumulative number of 5G base stations in the country has exceeded 690,000, and China’s 5G users have exceeded 150 million.

At present, there are only more than 800,000 5G base stations deployed globally, and the total number of 5G users worldwide is less than 200 million. It can be seen that China is already in a leading position in the progress of 5G construction.

While 5G is gaining popularity, China’s millimeter wave applications are also on the agenda. According to China IMT-2020(5G)The plan to join the group will be divided into three stages to promote 5G millimeter wave:

• In 2019, we will focus on verifying 5G millimeter wave key technologies and system characteristics;

• In 2020, we will focus on verifying the function, performance and interoperability of 5G millimeter wave base stations and terminals;

• Perform application verification in typical scenarios from 2020 to 2021.

At the Beijing Winter Olympics in 2022, China Unicom will adopt a 5G millimeter wave technology-based networking solution to provide network services for the Winter Olympics venues.

In addition to operators, many mobile phone manufacturers are also preparing for the commercial use of millimeter waves. The customized version of millimeter wave OnePlus 8 became China’s first smartphone to support 5G millimeter wave. Huawei Mate X also has a millimeter wave version, but it is not on sale.

In the relevant industry chain, Chi Yongsheng, vice president of China Unicom Network Technology Research Institute, pointed out that the domestic millimeter wave industry chain is relatively weak compared to foreign countries, and the degree of localization of core technologies and core devices is relatively low.

However, China has also made breakthroughs in 5G millimeter-wave chips. The millimeter-wave chip developed by Nanjing Network Communications and Security Purple Mountain Lab has reduced the cost per channel from 1,000 yuan to 20 yuan, and is expected to be commercially available in 2022.

Not only in China, more than 120 operators around the world have invested in millimeter wave research and development. What they are looking at is the huge application prospects of 5G millimeter waves and the considerable commercial potential.

According to GSMA forecasts, the contribution of millimeter wave 5G to global GDP will increase exponentially from 2020 to 2034. In 2034, it will contribute US$565 billion to global GDP and contribute US$152 billion in taxes.

At that time, when people talk about 5G, they may no longer think of mobile phones, and even have devices that can replace smart phones.

This article is from WeChat official account:Love Faner (ID: ifanr), author: Lee extraordinary