Cellular frequency ranges: getting to know the types and features
The article content
- What are cellular frequency bands?
- Why do cellular operators need multiple frequencies?
- A little about how cellular frequencies work
- Where did the frequency range come from
- Getting to know the 4th generation of cellular network systems
- Get to know the 5th generation of cellular communication systems
- Additional questions
Smartphone — This is an essential element of the life of a modern person. People everywhere use it to make calls, transfer data, and access the Internet. But not every user knows what technologies are used to organize the operation of mobile devices. Perhaps some of you will say, why go into all these details if the device already works. But not everything is so simple here. The point is that you can improve the performance of your device if you can understand all the details.
So, one of the most important parameters in this case will be such an indicator as radio waves, and in particular, the transmission frequency. Certain networks and bandwidths may serve different regions differently, some – better, others – worse. And a number of devices may be compatible only with certain radio frequencies, while they will not work with others at all. That is, both specialists and people whose professional activities are far from cellular communications should understand frequency ranges. This is the knowledge that will help you provide yourself with a convenient, stable and functional connection, high availability with reference to a specific country, or even region, and choose the best cellular operator and mobile device for yourself.
Now let's look in more detail at what the cellular frequency range is. Let's tell you why cellular network operators often have several frequencies. Let's describe how the cellular frequency range works and look at the solutions used today. We will answer a number of the most popular questions in this area.
What are cellular frequency bands?
Cellular frequencies are used by mobile devices to access cellular networks. It is with their help that calls are made, text messages are sent, videos are transmitted, and the ability to access Internet pages is provided.
Frequency of sound waves — is a physical term that defines the number of waves that will be generated per unit of time, specifically per second. They are measured in hertz (Hz). If the indicator turns out to be high, then this will indicate faster movement of the waves, but if it is low — on the contrary, slow. In cellular communications, we are talking about the frequency of sound waves that cellular devices use to maintain stable communications. The range here is such that the human ear does not react to them, that is, we simply do not notice them.
And all those frequencies that cellular network operators use today are presented in the range from 3 kHz to 300 GHz. All of them form the so-called radio frequency spectrum. Their distribution is handled by the Specialized Communications Commission and the National Telecommunications and Information Administration. They are the ones who distribute the entire spectrum into several ranges, which are called — stripes. That is, it will represent not just one particular cellular frequency, but a fairly wide range. So, for example, if they say that the 700 MHz frequency band is used, then in reality cellular communications will operate in the range from 699 to 798 MHz.
It turns out that cellular operators buy several of these frequencies from state radio broadcasting, and then configure them for communication with mobile network towers.
Why do cellular operators need multiple frequencies?
Cellular operators must have appropriate licenses not only to provide services, but also to use certain cellular communication bands. Often one license is issued for the entire strip. It is also called a block or channel. To ensure that the work of one operator does not overlap with others, different lanes are used. But for stable network operation, operators need to ensure its stability over a fairly wide range of the radio frequency spectrum. That is why they purchase blocks in different segments of the radio frequency spectrum. That is, they can have both low and fairly high frequencies at their disposal:
- Low frequencies are needed to ensure a stable connection in remote areas. Such signals are able to overcome fairly large distances and obstacles in their path.
- High frequencies cannot overcome obstacles and have a relatively short range. But they are capable of transmitting impressive amounts of data at high speed. This means that they will have higher functionality and reliability in different cities, including big cities.
- That is, if the operator has cellular frequency bands from the high and low range at its disposal, then it will be able to provide its services to the widest possible audience, both from cities and rural areas.
A little about how cellular frequencies work
As practice shows, most cellular operators have at their disposal a fairly impressive range of frequencies capable of covering large territories and a huge number of user audiences. But here it is still necessary to take into account such a point as the compatibility of user devices with certain frequencies. Modern manufacturers of smartphones and tablets, in principle, take into account the wide frequency range that exists on the market today and produce their products so that they provide a stable connection over a fairly wide range. That is, as soon as you activate your device, it will automatically connect to the frequencies of your cellular operator.
But at the same time, the method of signal transmission can be different and depends on what methods use certain ranges. There are 2 options here:
- FDD. These are full-duplex bands with frequency division channels. They consist of 2 different frequencies, which are separated by a special guard band. Thanks to this, they work completely in isolation, that is, they do not interfere with each other. Through one such band, information is sent to the tower of the cellular network operator via the so-called “uplink”. The other band is dedicated to receiving feedback from the cell tower, which is called the “downlink.” That is, thanks to this implementation of the structure, it is possible to simultaneously send and receive signals. If your device is connected to such a range, then you will observe a fairly high data transfer rate.
- TDD. These are time-division redundant communication bands. There is one frequency for both sending information and receiving a return response after a certain time interval. Despite the apparent complexity and presence of waiting time, the process of transferring data and voice is quite fast and efficient. The average user does not notice any delays in operation. But in this case it is necessary to provide a point synchronization system. This is especially true for 5G frequencies.
Where did the frequency range come from
They started talking about cellular communication frequency ranges literally as soon as cellular technology itself appeared. Its first generation was AMPS (Advanced Mobile Phone Service) technology. It provided the transmission of voice messages in the 5.8 GHz frequency range. Gradually, as the number of mobile phones in use by users increased, the opportunities that this frequency provided were not enough. After this, it was decided to open another band, with a frequency of 21.9 GHz. It was called the Personal Communications Service or, as we know it today, PCS. For quite a long time, cellular communications around the world used these 2 frequency ranges. By the way, 2G and 3G operate on the same part of the spectrum. But gradually, as 3 G technologies developed, the number of available bands began to increase significantly.
A new round of development in this direction began when smartphones appeared on the market. Along with making calls and sending text messages, these devices began to be used by users to provide a fairly impressive range of related services, including access to the Internet. In parallel with this, 4G technology also appeared on the market. She has already used the following frequency ranges:
- 600 MHz;
- 700 MHz;
- 1700/2100 MHz;
- 2300 MHz;
- 2500 MHz.
As we said above, lower frequencies allowed operators to work, including in rural areas, in remote areas.
From that time to today, the number of devices connected to the cellular network has been growing. And this trend will continue for quite a long period of time. Along with smartphones, it is also used by tablets and other gadgets, security systems, cars, drones, smart sensors, and much more that can also be classified as the Internet of Things. To meet the ever-increasing demands of the global market, cellular operators have launched the next generation of cellular technology — 5G. In some countries it has already become very widespread, in others — is just beginning its journey. Low band 5G ranges from 600 MHz to 1 GHz, Middle — from 1 to 6 GHz, and the upper — 29-39 GHz. Experts especially highlight mid-frequencies that are in a fairly narrow range of 3.7-3.98 GHz. They are called C-Band and, according to experts, its capabilities are significantly higher than those of 4G.
Now let's take a closer look at the frequency ranges of 4G and 5 G technology. Due to the fact that the 2nd and 3rd generation of mobile network systems are practically not used in practice today, we will not consider them.
Getting to know the 4th generation of cellular network systems
If we talk about 4G technology, then it is worth highlighting three groups of main parameters:
- 4G. The letter G itself, which stands next to the number — This is an abbreviation for generation. That is, if you see the term 4G, you can immediately understand that we are talking about the 4th generation of cellular communication systems. The functionality here is already much wider than that of the same 3rd generation. In particular, devices that operate on this technology can already process conversations and text messages, are characterized by stable interaction with fast Internet, and transmit huge amounts of data quickly and without lags. It was this generation that provided the opportunity for the emergence of such platforms as YouTube, Facebook, Netflix etc.
- WiMAX. This is a technology called Worldwide Microwave Interoperability. It was the very first standard in 4G technology and was widely used until about the beginning of 2016. It was gradually replaced from the market by LTE technology.
- LTE, or as it is often called 4G LTE. Represents the standard for long-term development. It is based on improving technology to ideal 4G. In view of this, there is such a term as true 4G networks, called 4G LTE-A (Verizon), 5Ge (AT&T) or 4G LTE+.
Get to know the 5th generation of cellular communication systems
5th generation of cellular communication systems — This is the newest network standard on the global market today. It was designed to provide the highest possible data transfer speeds while minimizing latency. It has huge capacities and impressive capabilities. It is characterized by high stability and reliability in operation. By analogy with the 4th generation, real 5G requires data download speeds starting from 1 Gbit/s, and the latency does not exceed one millisecond. These are much more impressive figures compared to the capabilities of 4th generation cellular communications. But still, not all 5G networks that are presented on the modern market are the same. There are 4 types of 5G depending on the frequency ranges used:
- Low frequency. Operates on a band with a frequency of up to 1 GHz. The coverage is quite identical to 4G, but soon it will be slightly higher, although not significantly. Experts say that this band — this is the basis for building nationwide coverage in different parts of the country.
- Mid-frequency. Bands with frequencies from 1 to 6 GHz are used here. The data transfer rate here is already significantly higher than that of the previous version, which makes it optimal in terms of the ratio of speed, power, penetration and propagation range. It is aimed at covering densely populated areas, those where the demand for mobile services is quite high.
- High frequency. It is also called 5G mmWave. Operates in the frequency range from 24 to 39 GHz. They are distinguished by ultra-high speeds for transmitting large amounts of data, have a minimal time delay, but they cannot penetrate deep into a building and overcome long distances. This option is optimal for use in densely populated regions. Where there is a huge amount of infrastructure.
- C-Band. This is the range that is widely used by satellite television operators. It has a narrow band, literally sandwiched between Wi-Fi 2.4-5.0 GHz. But here the speed is quite high, and the coverage is quite decent.
Which frequency range is currently used by certain global operators can be found in the relevant reference data. We also suggest studying MCC MNC list.
Now we will dwell in more detail on a number of related issues in the field of frequencies from cellular communications.
Why are cellular frequencies so important? Every cellular network user must know what communication frequencies his operator uses in order to buy a device that will work stably in this range or select a service provider capable of meeting exactly your needs in terms of quality, data transfer speed, signal range, etc. The point is is that your smartphone or other device must be compatible with the desired bands and networks that are available from your telecom operator. Otherwise, it simply won’t work. Even minor incompatibility can cause connection problems.
Will the same phone work in the frequency ranges of different operators? In principle, it will. Similar restrictions, providing for the maintenance of only one frequency band, were used in the 3rd generation of cellular communications. Today, technologies such as CDMA or GSM are already a thing of the past. This means that your device will work with multiple operators if the frequency range matches. Therefore, the more bands your device and the operators you work with, the more stable and reliable the connection will be.
How to check which frequency bands your phone supports? One of the simplest solutions here — view the technical specifications of your smartphone or tablet. Here it will be enough to simply use any browser, enter the make and model of the device into it and literally in a few seconds you will receive a list of technical characteristics. Next, you need to go to the page of your telecom operator. Often here you will find built-in online tools that will allow you to determine the compatibility of a particular smartphone with the frequencies of operators and, accordingly, with the services that they provide. You can also use special tables that show operator ranges and compare them with the parameters that your device supports. Also here you can see which other service providers you can work with from your smartphone or tablet. You can also find out the cellular frequency on which your device operates directly through a special service menu. On smartphones using the Android operating system it is called Service Mode, on Apple gadgets — Field Test. To call this menu, you just need to dial a special service number from the keyboard. Depending on your Android device model, you will need to enter one of 3 options: *#0011#, *#*#4636#*#*, or *#*#197328640#*#*. On Apple smartphones, the service menu is called up using the code *3001#12345#*. And do not forget to press the call button in any case after typing the characters. A menu with technical data will open in front of you, but in this case you will be interested in the frequency at which your device is currently operating.
As you can see, cellular communication technologies today are developing very rapidly, trying to satisfy the ever-increasing demands of the user audience. To ensure the most stable connection and data transfer, regardless of what region you are in at a given time, you need to be well versed in frequency ranges and understand which operator will be most suitable for you at a given time.