What are the 5G frequencies "mmWave" and "SUB6"? A thorough explanation of the differences, advantages and disadvantages

The next-generation communication standard "5G" is beginning to spread around us. With features such as high speed, large capacity, low latency, and multiple simultaneous connections, it is expected to bring about major changes to our lives and businesses. However, knowledge of "frequency" is essential to fully understand its performance.

In this article, we will explain in detail the mechanism of 6G, its advantages, disadvantages to know, and future prospects, focusing on the differences between the main frequency bands used in 5G, "mmWave" and "Sub5". Let's learn the basics about "frequency 5G", the core technology of the 5G era.

What is 5G frequency?

The relationship between frequencies and 5G is an important point that many people are concerned about: "Why will communication speeds become faster?" First, let's explain the basics of frequencies and 5G.

What is Frequency?

Frequency refers to the number of times a wave, such as an electric wave or a sound wave, repeats per second. It is expressed in units of Hz (Hertz). For example, a wave that vibrates 1 times per second is 1 Hz.

These radio waves are used by smartphones, televisions, radios, etc. to communicate, and each radio wave is assigned a different frequency.

The higher the frequency, the shorter the wavelength (the length of one wave) and the more information it can carry at one time, but it has the property of being difficult to reach long distances and being easily affected by obstacles.On the other hand, the lower the frequency, the longer the wavelength, the easier it is to reach long distances and is relatively resistant to obstacles, but the amount of information it can carry at one time is smaller.

What is 5G?

5G is the abbreviation for "5th generation mobile communications system," and is a communications standard that achieves even higher speeds, larger capacity, and lower latency than 4G. It is expected to be applied not only to high-load services such as video streaming and online games, but also to industrial robots and autonomous driving.

The main characteristics of 5G are:

• High speed/large capacity
• Low latency
• Multiple Connections

5G has a much faster communication speed than conventional 4G, and the amount of data that can be handled at one time has also increased dramatically. This means that video download times are significantly reduced, making it possible to enjoy higher quality video content.

In addition, 5G has extremely little time lag in communications, and is expected to be used in fields that require real-time performance, such as remote medical care and autonomous driving.

With 5G, not only smartphones but also all the things around us, such as home appliances and cars, can be connected to the Internet at the same time. This is expected to lead to widespread use in a variety of areas, such as autonomous driving and smart cities.

Main frequencies used in 5G

To achieve 5G communications, radio waves with frequencies suited to their characteristics are used. The frequency bands primarily used by 5G each have different characteristics, and understanding these is important in understanding the capabilities of 5G.

There are three main frequencies used in 5G:

• Sub6
• millimeter wave
• NR conversion        

Here's a table comparing them all:

Features	Sub6	millimeter wave	NR conversion
frequency band	Less than 6GHz	28GHz band etc. (30GHz to 300GHz)	Existing 4G frequency bands (e.g. 700MHz to 3.5GHz)
communication speed	Relatively fast	Ultrahigh speed	Faster than 4G but slower than Sub6 and mmWave
delay	Low latency	Ultra-low latency	Lower latency than 4G
Coverage Area	Relatively spacious	narrow	Wide (utilizing existing 4G areas)
Strength against obstacles	Relatively strong	weak	Relatively strong
Main role	Wide-area 5G coverage and stable communications	Providing ultra-high-speed, large-volume communications in specific areas	Rapid expansion of 5G areas and improved connection opportunities
base station	Existing 4G base stations can be partially utilized	Many new installations required	Existing 4G base stations can be utilized to the fullest extent

SUB6

Sub6 is one of the frequency bands used by 5G and refers to the frequency band below 6GHz. This frequency band has characteristics similar to the frequency band used by 4G (LTE).

Therefore, its advantage is that radio waves can reach relatively long distances and can easily go around obstacles such as buildings. This property makes it suitable for covering a wide area, and it is possible to efficiently expand 4G areas while utilizing some of the existing 5G base station equipment.

On the other hand, compared to the higher frequency band known as millimeter waves, the amount of data that can be carried at one time (communication speed) is somewhat inferior. However, due to this good balance, it is playing a central role in expanding area in the early stages of 5G adoption.

millimeter wave

NR is a technology that allows the frequency bands currently used for 4G to be used for 5G as well.

By utilizing 5G technology not only in new frequency bands dedicated to 6G, such as Sub4 and millimeter waves, but also in frequency bands that have been used for 5G up until now, it will be possible to deploy 5G areas more quickly and widely.

Specifically, a technology called Dynamic Spectrum Sharing (DSS) is used to efficiently share the same frequency band between 4G and 5G users. This has the advantage that telecommunications carriers can start providing 5G services while making maximum use of existing base station facilities, without having to wait for new frequency band allocations.

However, because the communication speed and capacity of NR frequency bands were originally designed for 4G, we cannot expect the same high performance as 6G-dedicated frequency bands such as Sub5 and mmWave. Nevertheless, they play an important role in the early expansion of 5G areas and making it easier for users to connect to 5G.

Frequency Benefits of 5G

The practical application of 5G communications will bring various benefits to our lives and society. These benefits will vary depending on the characteristics of the frequency bands used.

Here we will explain the benefits that Sub5 and millimeter wave, the main frequency bands used in 6G, each offer.

Benefits of SUB6

6G using the Sub5 frequency band plays a central role, especially in the early stages of 5G rollout.

First, 5G signals can reach relatively long distances and are relatively resistant to obstacles such as buildings, so they can cover a wide area efficiently. This means that the benefits of XNUMXG will be available relatively quickly not only in urban areas but also in suburban and rural areas.

In addition, since 4G networks can be built while reusing some of the equipment of existing 5G base stations, telecommunications carriers will have the advantage of being able to smoothly expand their 5G area coverage while keeping capital investment costs down.

Furthermore, although it is not as fast as millimeter wave, it is still faster and can transmit large amounts of data than 4G, which means it can provide a more comfortable communication environment for services that many users use on a daily basis, such as watching high-definition videos and playing online games.

Due to these advantages, Sub6 will play a fundamental role in the spread of 5G and the provision of stable services.

Advantages of mmWave

5G, which uses the millimeter wave frequency band, has different advantages over Sub6 due to its characteristics.

The biggest advantage is the overwhelming "ultra-high speed, large-capacity communication."

Millimeter wave has a much wider bandwidth than Sub6, making it possible to download large amounts of data such as movies in just a few seconds and enjoy high-definition VR (virtual reality) and AR (augmented reality) content without delay.

This will not only dramatically improve the entertainment experience, but is also expected to bring about major innovations in the industrial sector.

Another benefit is "ultra-low latency."

Because the time lag in communication will be extremely small, advanced applications that require immediacy will become possible, such as a doctor in a remote location operating a robot arm to perform surgery or precise control of factory machinery in real time.

In addition, the wide bandwidth of mmWave will further enhance its "multi-connection" characteristic, which allows multiple devices to be connected simultaneously. This will make it easier to maintain a stable communication environment even in crowded places such as stadiums and large-scale event venues.

Due to these advantages, millimeter waves are expected to be used as an innovative technology to support the social infrastructure of the future.

Frequency Disadvantages and challenges of 5G

While 5G communications offers many benefits, there are also disadvantages due to the characteristics of the frequency bands used and challenges that must be overcome.

In particular, Sub6 and mmWave have different characteristics and therefore pose different problems.

This article will explain the disadvantages of 5G frequency bands. Understanding these points will give you a more realistic view of the current state of 5G technology and efforts toward its future development.

Disadvantages of SUB6

While 6G, which uses the Sub5 frequency band, has the advantages of wide area coverage and ease of implementation, it also has some disadvantages, the biggest of which is that communication speeds are slower than those of the mmWave band.

The main features of 5G are "ultra-high speed and large capacity," but Sub6 alone may not be able to fully enjoy these benefits. In particular, for cutting-edge services that require very large amounts of data communication or extremely low latency, the performance of Sub6 may be insufficient.

Additionally, on a global scale, the frequency bands available for use as Sub6 vary by country or region, and available bandwidth may be limited.

If the bandwidth is narrow, the amount of data that can be transmitted at one time is also limited, so it is possible that the speed will not be as fast as expected. Furthermore, since it is close to the existing 4G frequency band, careful area design may be required, such as measures against radio wave interference.

Understanding these disadvantages, appropriate use of millimeter waves and technical ingenuity will be essential to improving the quality of 5G services in the future.

Disadvantages of mmWave

Millimeter waves are a very important frequency band for realizing the ultra-high speed, high-capacity communications of 5G, but they also have some disadvantages due to their characteristics.

The biggest challenge is that radio waves have an extremely strong tendency to travel in a straight line, making them extremely vulnerable to obstacles. Walls, buildings, rain, fog, and even the human body can block or attenuate radio waves.

As a result, in order to ensure a stable communication area using millimeter waves, a large number of base stations must be installed closely spaced, which means that infrastructure development is time-consuming and costly.

In addition, because radio waves have difficulty reaching long distances, the range that can be covered by a single base station is significantly narrower than that of Sub6. This is a major constraint, especially in rural areas and outdoors where a wide area needs to be covered.

Furthermore, smartphones and devices that support mmWave tend to be more expensive to manufacture than models that only support Sub6 due to more complex antenna designs, which could have an impact on device prices.

To overcome these disadvantages, research is underway into improving beamforming technology (technology that concentrates radio waves in a specific direction) and into more efficient base station placement.

Frequency The future of 5G

5G technology is still in its infancy and is expected to evolve further in the future.

In addition to improving communication speeds and expanding service areas, it is expected that the way frequencies are used will also evolve to create new services.

This chapter explores frequency trends, which will be a key factor in shaping the future of 5G.

Specifically, we will focus on the following points:

● New frequency band allocation
● Technical issues

Through this information, we will explore the possibilities of how 5G will transform our society in the future.

New frequency band allocation

In order to maximize the performance of 5G and meet diverse needs, it is essential to secure and allocate new frequency bands in addition to the ones currently in use.

In particular, research and development is being conducted on frequency bands even higher than millimeter waves (such as terahertz waves) in order to achieve faster, larger-capacity communications. These unexplored frequency bands have the potential to secure huge bandwidths, and are expected to become the foundation of next-generation communications technology, including the future 6G (sixth generation mobile communications system).

In addition, there are plans to reorganize and allocate additional frequencies to existing bands in order to use them more efficiently. For example, there are moves around the world to repurpose some of the frequency bands currently used for television broadcasting and satellite communications for mobile communications systems such as 5G.

This aims to make effective use of limited frequency resources and promote the further sophistication and spread of 5G services. However, the allocation of new frequency bands requires careful consideration and preparation, including international coordination, coexistence with existing wireless systems, and evaluation of the effects of radio waves on the human body.

Technical challenges

While the widespread adoption and advances in 5G are expected, several technical challenges must be overcome to bring it to fruition.

First, the expansion of millimeter wave coverage remains a major challenge. Because millimeter waves are vulnerable to obstacles and have a small coverage area, detailed installation of base stations is essential, but this requires huge costs and time. There is a need to develop technology that can build millimeter wave coverage more efficiently and at low cost, as well as devise new installation methods.

Another issue is power consumption. 5G, especially millimeter wave communications, tends to consume more power at base stations and terminals than 4G. From the perspective of reducing environmental impact and extending battery life, it is important to further improve power-saving technology.

Furthermore, in order to realize the "ultra-low latency" characteristic of 5G for more applications, optimization of the entire network and evolution of edge computing technology are necessary.

In addition, with the spread of IoT (Internet of Things) devices that take advantage of the multi-connectivity of 5G, strengthening security measures will also become an urgent issue. Overcoming these technical challenges one by one will maximize the potential of 5G and become a force that truly transforms society.

Summary

This article focuses on frequency, which can be said to be the core of 5G communication, and explains everything from basic knowledge to the characteristics of the main frequency bands used in 5G, Sub6 and millimeter waves, their respective advantages and disadvantages, and future prospects.

As 5G becomes more commonplace in the future, understanding how it works, particularly its frequency characteristics, will be helpful in gaining a deeper understanding of this new technology and making use of it.

5G technology has the potential to bring about major changes in society. Correctly understanding the characteristics of frequency bands will be the key to next-generation service strategies, from choosing a smartphone to IoT business and smart city initiatives.