The modern smartphone is a sophisticated communication device that processes gigabytes of data daily through networks of various standards. For owners of Xiaomi, Redmi and POCO devices, the issue of hardware compatibility with the frequencies of local operators is especially urgent. Often users are faced with a situation where the phone catches the network, but the speed of the Internet leaves much to be desired, or the device does not see 4G at all in a particular location.
Understanding how your radio works not only helps you diagnose communication problems, but also helps you make smart choices when you buy your device, especially if you’re planning to travel abroad. In this article, we’ll take a closer look at the technical aspects of frequency management, how to check them through hidden menus and third-party utilities. You’ll learn to distinguish between hardware support ranges and software constraints, and you’ll be able to conduct deep network diagnostics yourself.
Before we get to the complex manipulations, we need to understand the basic terminology: mobile communication is divided into generations: 2G, 3G, 4G (LTE) and the latest 5G. Each generation operates in a certain spectrum of frequencies, which is divided into band numbers. For example, in Russia and the CIS countries, the most important bands are Band 3 (1800 MHz), Band 7 (2600 MHz) and Band 20 (800 MHz). If your Xiaomi does not support one of the key bands for your region, stable coverage is not worth waiting.
Why you need to check supported ranges
Many users mistakenly believe that if a phone shows “4G” or “LTE”, it will use the full potential of the network.In fact, the device can connect to a less busy but slower range, negating high-speed frequencies due to their lack of support in hardware. Frequency check is critical when buying smartphones imported from other countries, since Chinese versions of Xiaomi often have a stripped-down Band set compared to global modifications.
Also, knowing the frequencies supported helps you understand why thick-walled buildings are bad. Low-frequency bands like the Band 20 have better penetration but require appropriate hardware support. If your phone's specifications don't have this range, cellars and lower floors can completely lose communication.
⚠️ Note: Hardware frequency support is determined by the modem installed. Software methods (firmware, patches) can not add support for the missing range, as this is a physical limitation of components.
The test is also relevant for those who use a smartphone as a router or modem for Internet distribution. Frequency aggregation (LTE-A), which allows you to sum up the speed of several bands at once, only works if the device and the operator tower support the same Band combinations. Without accurate data about your device, it is almost impossible to set up the optimal network mode.
Using the Engineering Menu for Diagnostics
The fastest and most reliable way to know the current connection status and supported modes is to use Xiaomi’s built-in engineering menu, which provides access to the radio settings without the need to install third-party software. USSD-code that works on most devices under control MIUI hyperos.
To get into the testing menu, open the Phone app and dial ##4636##. Immediately after entering the last star, the hidden Check menu will open. You are interested in Phone Information, which displays the current network status, connection type and, most importantly, mode switching ability.
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If #4636### doesn’t work, try entering it through the Engineering Mode app, which can be found in the app directory or downloaded from Mi GetApps.
In the window that opens, look for Set Preferred Network Type. Clicking on the dropdown list will show all the modems your modem theoretically supports. However, here's a nuance: this list shows logical modes of operation, not physical frequencies. For detailed information about specific megahertz, you'd better use the "Run a ping test" button or go to the detailed information about the cell.
At the bottom of the engineering menu, you can often see the current cell (Cell Info) and calculate the Band from the EARFCN, and you can force your phone to LTE Only mode to check if there is any 4G coverage in your area, ignoring the fallback on 3G.
☑️ Checking in the engineering menu
Frequency analysis with third-party applications
Xiaomi’s regular tools provide a general view of the network, and for professional analysis that will show the list of frequencies supported by the device (not just currently active), specialized utilities are the best suited, with the leader in this field being the NetMonster app, which can read data directly from the modem.
Once installed and authorized, NetMonster displays the Cell and Capabilities tabs, which will provide the information you want, and will provide a complete list of supported bands for 2G, 3G, 4G and 5G. Supported frequencies are usually marked green or ticked, and those that are not available in the current location are gray.
- 📡 NetMonster: Best app for detailed viewing of frequency aggregation and Band. CA (Carrier Aggregation in real time.
- 📶 CellMapper: A powerful tower mapping tool that lets you see what frequencies the operator is giving away at your point and check them against the capabilities of the phone.
- 🔋 AIDA64 or CPU-Z: The "Device" or "Network" section shows basic connection information, but is less informative than NetMonster.
Another useful tool is G-NetTrack Lite, which allows you to log a connection and see detailed technical information about the signal. Unlike NetMonster, the interface may seem complicated, but the data here is presented in the rawest and most accurate form.
⚠️ Note: Apps like NetMonster on Android 10 and higher may require additional permissions or activation via the Internet. ADB, Google has restricted access to cell data for privacy reasons.
Decoding of designations and communication standards
When you look at Xiaomi’s specifications on the manufacturer’s website or in apps, you’ll come across a variety of acronyms, and understanding their meaning is essential for correct data interpretation. First of all, look at FDD-LTE and TDD-LTE. The former is used for symmetric data transfer and is popular in Europe and Russia, the latter is asymmetrical and is common in Asia.
Frequencies are divided into groups. Low frequencies (up to 1 GHz, for example, Band 20) provide broad coverage in rural areas. Medium (1-2 GHz, Band 3, Band 7) balance coverage with speed in cities. High frequencies (above 2 GHz, Band 38, Band 40) provide maximum speed, but have a short range. Frequency aggregation allows you to combine these bands to increase throughput.
LTE category designations are common in the specifications, like Cat 6, Cat 12, or Cat 15. The higher the category, the more ranges the modem can handle at the same time, and the higher the theoretical speed. However, even if the phone supports Cat 15, but the carrier does not use aggregation in your region, you will not feel the difference.
Band and frequency correspondence table
The 5G NR (New Radio) standard is divided into two bands: FR1 (Sub-6 GHz) and FR2 (mmWave). Xiaomi smartphones sold in Europe and Russia usually support only FR1. American versions can have mmWave support, which can be visually determined by the presence of characteristic window antennas on the device body, although in our latitudes these frequencies are not yet used in mass.
Comparison of frequencies in different regions
Geography of frequency usage varies greatly: What works in Moscow may not work in Berlin or Beijing. Global versions of Xiaomi usually have the widest range of supported frequencies to cover the requirements of most countries. Chinese versions (CN Version) often lack Europe-important bands like the Band 20, making their use outside of China problematic.
Below is a table of the main ranges used by Big Four operators in Russia and CIS countries, to compare with the capabilities of your device:
| Range (Band) | Frequency (MHz) | Type of network | Meaning to the user |
|---|---|---|---|
| Band 3 | 1800 | 4G LTE (FDD) | Main range in cities, high speed |
| Band 7 | 2600 | 4G LTE (FDD) | Additional capacity in megacities |
| Band 20 | 800 | 4G LTE (FDD) | Coverage in and out of buildings |
| Band 38 | 2600 | 4G LTE (TDD) | Used by MTS and Yota to unload networks |
If you are planning a trip, be sure to check the frequencies of the operator of the destination country. In Europe, the Band 20 is critical, without which the phone can switch to a slow EDGE outside the city. In the US and Canada, the situation is even more complicated: Band 12, Band 13 and Band 17 are critically important there, support for which is often not available in Redmi budget models.
The impact of firmware on the operation of the radio module
Many users are wondering: can a flashing phone add support for new frequencies? The answer lies in the difference between software and hardware. The firmware contains (configuration files) that tell the modem what frequencies are allowed to use in a particular region. However, if the physical radio part (RF front-end) does not have filters and amplifiers for a certain frequency, no firmware will force the phone to work in this range.
However, changing the region in the phone settings can affect the priority of network search. Xiaomi has a hidden region change feature that sometimes changes the set of displayed Band in the engineering menu, but this is only a software masking. Moreover, installing global firmware on a Chinese device (and vice versa) without unlocking the bootloader and correct firmware reflash can cause some frequencies to fail due to calibration mismatch.
⚠️ Note: Experiments with changing regional modem settings through ADB-Use the adb shell command only if you are confident in your actions and know the exact name of the region (for example, use the adb shell command, RU for Russia).
There is a concept of "regional patches" that enthusiasts create to activate hidden capabilities, but in today's environment, when operators require certification of devices (VoLTE, VoWiFi), such methods become risky.
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The firmware can change the priorities of network search, but it cannot add physical support for missing frequency bands.
5G issues and future standards
With the development of networks of the fifth generation, the issue of compatibility becomes even more acute. Xiaomi smartphones of the flagship and mid-segment are already massively equipped with Snapdragon and Dimensity modems with support 5G. However, the list of supported 5G-range (n1, n3, n28, n78 etc.) can vary greatly even within the same model.
In Russia and Europe, the main 5G range is still n78 (3500 MHz). If your phone supports only Chinese 5G bands (for example, n41 or n79), then in the European zone 5G will not work, despite the appropriate marking on the box. 5G support is checked by the same methods: through NetMonster or the engineering menu, where the list of preferred networks should be NR or 5G.
Also worth considering is NSA (Non-Standalone) and SA (Standalone) technology. The first 5G networks work in conjunction with 4G (NSA), and the phone needs to confidently hold LTE to run 5G. Future SA networks will work independently. Make sure your tariff and phone settings allow for these modes, although for now it's automatic in most cases.