The situation when expensive flagship Xiaomi or budget Redmi lose the network at the most inopportune moment, familiar to many users. the fall in Internet speed, interruptions of voice calls and constant search of the network can be caused not only by distance from the operator’s base station, but also by incorrect software settings of the device. Often the standard algorithm for network selection in Android works inefficiently, clinging to congested frequencies instead of more stable but less powerful signals.
Fortunately, the Android operating system provides access to deep system settings through what is known as an engineering menu.It is a hidden interface designed for engineers and testers that allows you to manually control the parameters of the radio module. In Xiaomi smartphones, access to these features is somewhat limited compared to pure Android, but there are proven ways to activate the necessary tools to stabilize the connection.
In this article, we will look at legal and safe ways to improve signal reception that do not require superuser (Root) rights. We will discuss how to choose the right type of network, fix a specific LTE frequency and use system codes to diagnose the antenna module. Proper network priorities often work wonders even in areas of uncertain reception, allowing your device to work at the limit of its physical capabilities.
Diagnostics of current network status and signal level
Before making changes to the modem configuration, you need to objectively assess the current situation. Standard "rods" in the corner of the screen are only a conditional graphical display that does not give an accurate idea of the quality of the communication channel. For professional diagnostics, the RSRP (Reference Signal Received Power), which is measured in decibel-milliwatts (dBm) and shows the real power of the received signal.
To see the exact, go to Settings. → The phone. → All specs → Status SIM-maps (the path may vary slightly depending on the version) MIUI You're interested in the signal level parameter here. 0 are ideal, while the values below -110 dBm is considered critical. Understanding these numbers will help you evaluate the effectiveness of subsequent settings.
Also worth noting is the Signal-to-Interference-plus-Noise Ratio (SINR), which shows the ratio of signal to noise. Even with a high signal level (RSRP), low SINR will lead to low Internet speeds due to a large number of data errors. If the SINR falls below 0 dB, the communication will be almost inoperable, and no software settings will help without an external amplifier.
Activation of the engineering menu and test menu
On Xiaomi smartphones, the classic engineering menu, available under #4636##, is often blocked by the manufacturer or redirects the user to standard settings. However, there are several ways to get around this limitation and get into the Testing section, where the key parameters of the radio module are located.
The first and easiest way is to use a dedicated activator application, such as Activity Launcher or a specialized utility like Xiaomi Engineering Mode from Google Play, which allows you to run hidden system activities directly. Once installed, look for an item associated with com.android.settings that contains the word Testing or RadioInfo.
⚠️ Attention: Changes to the engineering menu may result in the total disappearance of the network or incorrect operation of the communication module.
If you don't want to use third-party apps, you can try activating the menu via ADB (Android Debug Bridge) by connecting your phone to your computer. To do this, turn on USB debugging in the developer menu and run a test activity command, which is more reliable and works on most of MIUI Global and China firmware.
Command to activate via ADB
Configure the preferred type of network
One of the most effective measures to improve communication stability is forced network type selection. Automotive mode often tries to keep the phone in the 4G/LTE coverage area, even if the signal there is weak and unstable, instead of switching to a longer-range 3G or 2G. In the Phone Information menu, there is a drop-down list "Install preferred network type".
You can see a lot of options here, like NR/LTE/GSM, LTE only, WCDMA preferred, and others. For voice communications in areas of poor coverage, it is often more profitable to forcefully switch to 3G (WCDMA), since this standard better breaks walls and has a longer range of base stations. For the mobile Internet, on the contrary, it makes sense to try (lock) only LTE so that the phone does not jump between standards.
- 📶 LTE Only – use only if you are in the safe reception zone 4G You need top speed, but be prepared for the fact that incoming calls may not pass without VoLTE technology.
- 📞 WCDMA Only is ideal for voice calls in a basement, village or building with thick walls, where 4G no-fish.
- 🔄 NR/LTE/TD-SCDMA/GSM — standard mode for modern Xiaomi smartphones, providing a balance between speed 5G/4G and cover old networks.
Experiment with these settings depending on your location. Sometimes, simply selecting GSM only for a few minutes and returning to automatic mode helps the modem to re-register and choose a more optimal base station.
💡
If after selecting the mode "LTE Only" lost the Internet and calls, just restart the device - the settings will reset to the standard operator values.
Selecting the frequency range (Band Locking)
The most advanced method of optimization is the hand-held Band Locking. Communication operators use different frequency bands (Bands): low (for example, Band 20, 800 MHz) have excellent coverage but low speed, and high (Band 3, 1800 MHz; Band 7, 2600 MHz) give high speeds but do not penetrate obstacles well.
In Xiaomi’s engineering menu (often available through hidden menus or special lane switching apps), you can turn off extra frequencies. If you’re far from the tower, leave only low frequencies (B20, B8). This will cause the phone to ignore the weak high frequency signal and hold onto a stable low frequency signal. In urban areas, on the contrary, a shutdown can speed up the Internet.
| Range (Band) | Frequency | Characteristics | Recommendation |
|---|---|---|---|
| Band 20 | 800 MHz | High penetrating capacity | For the village, the basements, the buildings. |
| Band 3 | 1800 MHz | Basic urban standard | Universal choice |
| Band 7 | 2600 MHz | High speed, small radius. | Only downtown. |
| Band 38/40/41 | 2300-2500 MHz | Specialized LTE (TDD) | To unload the network during peak hours |
A switching app is often required to control the bands, as the standard menu is MIUI And you have to be careful, if you turn off all the lanes that are supported by the nearest tower, the connection will disappear completely, and then only rebooting the phone or retrieving it will help. SIM-map.
Resetting network settings and re-registration
Sometimes the problem is not physical parameters, but software failure, when the phone gets stuck at a certain base station, even if another, more powerful one appears nearby, in which case a complete reset of network settings helps, this action will delete stored Wi-Fi passwords and Bluetooth pairs, but often effectively solves mobile problems.
You can reset via the Settings menu → Connect and Sharing → Reset Wi-Fi, mobile networks and Bluetooth. After this operation, the phone completely rewrites the modem configuration files and starts searching the network from scratch, choosing the best option available. This is similar to turning off and turning on flight mode, but much deeper.
☑️ Checklist before network reset
It is also worth checking the settings of the access point (APN). Wrong settings APN They can cause slow Internet, even if you have a very good signal level. Go to your mobile network settings, select yours. SIM-map and access points (APN). Click the reset button to the default settings or create a new point with the options recommended by your carrier.
Hardware constraints and external factors
Remember that software settings cannot bypass the laws of physics: If a Xiaomi smartphone has a weak antenna or it is damaged (for example, after a fall or poor repair), no engineering menu will make the signal more powerful, and reception is also affected by metal phone cases, thick walls with rebars and electrical interference.
In some cases, removing the case helps, especially if it contains metal elements or magnets, magnets can adversely affect the operation of the antenna module, and overheating the device leads to a decrease in the power of the transmitter to protect the components, which also impairs communication.
⚠️ The use of third-party stickers-"antenna" or foil, which are glued to the battery or under the back cover, in most cases is a marketing move and does not give a real signal increase, and sometimes even shields the standard antenna.
If you are in a stationary point with poor coverage (office, cottage), the best solution is to use Wi-Fi Calling technology, if it is supported by your operator and smartphone, which allows you to make calls over the Internet, completely ignoring the quality of the cellular network.
💡
Software tuning can improve connection stability, but it cannot increase the physical power of receiving antennas beyond factory constraints.