How to improve the reception of cellular communication on Xiaomi smartphones: from MIUI settings to hardware solutions

Cell phone quality issues on Xiaomi smartphones are one of the most common complaints users have had. Even the flagship Mi 13 Ultra or Redmi Note 12 Pro+ models sometimes lose network in places where other brands are operating consistently, and the reasons may lie in both the software settings of MIUI and the hardware features of the communication module. In this article, we will discuss all possible ways to improve the signal, from basic actions to advanced methods, including changing network parameters and physical modification of the device.

It's important to understand that weak signal is not always the fault of the smartphone. Often the problem is with congestion of the operator's tower, terrain or interference from buildings. However, even in such conditions, the right Xiaomi settings can make the most of the available coverage. We have tested all methods on devices with MIUI 14 and HyperOS, but most of the solutions are relevant for older versions of the firmware.

Before you start settings, check the obvious: whether your Xiaomi is in the coverage area of the operator (use coverage maps on the sites of MTS, Beeline, MegaFon or Tele2). If the signal is absent even in open areas - the problem may be in the SIM-map or antenna module of the smartphone.

Basic checks: SIM-map, network mode and operator

Start with some basic steps that often solve the problem without deep tuning. The first thing you need to do is to reboot your smartphone. This will reset the temporary errors of the communication module and update the registration in the operator's network. If the reboot did not help, go to the checkout. SIM-map.

Remove the tray for SIM-Check the card and see if it's damaged, like chip scratches, dirt, or deformation. Xiaomi devices with a hybrid slot (like the Redmi Note 11) have a second installer that's not installed correctly. SIM The memory card can block the main contacts. SIM, This is what causes the signal to drop. SIM In other words, if you have a dual-SIM, or replace it with a spare.

Check the network settings:

1. Go to Settings. → SIM-maps and mobile networks.
2. Choose yours. SIM-map and open the network type.
3. Install 4G (preferably) or 5G/4G/3G/2G (auto).

⚠️ Note: If you choose the mode only 4G or 5G, The smartphone will not be able to switch to 3G/2G weak signal, which can lead to a complete communication interruption in some areas.

If you have Xiaomi with VoLTE (voice over 4G) support, make sure the feature is enabled:

1. Go to Settings. → SIM-maps and mobile networks → [Yours. SIM] → Enable VoLTE.
2. Activate the switch. Some firmware may need to reboot.

VoLTE improves communication quality in areas with unstable 4G, as voice calls go through the same channel as the Internet.

2. Optimize MIUI settings to amplify the signal

MIUI hides a number of parameters that can affect communication quality, one of which is the power saving mode for the mobile network, which by default can limit the power of the communication module to save battery power, to disable this limitation:

Open Settings → Battery and Performance → Power Saving Mode and select No restrictions on mobile data. Also check the settings of a particular application (such as Google Maps or messengers) if the signal is lost only when using them.

Another hidden parameter is network priority. MIUI You can manually specify the preferred network type for each SIM-map:

1. Enter the combination in the Phone app: ##4636##.
2. Select Phone Information.
3. Scroll down to Set your preferred network type.
4. Choose. LTE only (if you have a stable condition) 4G-coating NR/LTE/TD-SCDMA/GSM Auto for automatic selection.

⚠️ Note: Not all operators support 5G SA (standalone if you choose NR/LTE/... The network is lost, return the setting to LTE only.

On HyperOS devices (such as Xiaomi 14 or Redmi K70), the path to the engineering menu may be different. If code ##4636## doesn't work, try:

Settings → About Phone → MIUI version (shap 7 times to unlock the developer mode)


Next: Settings → Additional → For developers → Enable the engineering menu

Make sure that SIM-map inserted correctly

Select 4G network mode (preferably)

Enable VoLTE (if supported)

Disable energy saving for the mobile network

Check Network Priority in the Engineering Menu-->

3. Updating the firmware and modifying the radio module

Manufacturers regularly release updates to correct errors in the communication module.

1. Go to Settings → About the phone → System update.
2. Click Check Updates and install the latest version of MIUI or HyperOS.

If the update didn’t work, the problem could be a radio module (firmware for modem). XDA Developers and 4PDA forums often post separate modem firmware that improves reception. For example, for the Redmi Note 10 Pro, there is a modified radio module with improved support for B20 (800 MHz) bands that better catches the network in rural areas.

To update the radio module:

1. Download a firmware file for your model (for example, NFC_modem_fix.zip for POCO F3).
2. Rename it to modem.img and place it in the /sdcard folder.
3. Reboot to Fastboot (clip Power + Volume Reduction).
4. Connect your smartphone to your PC and execute the command: fastboot flash modem_a modem.img fastboot flash modem_b modem.img fastboot reboot

⚠️ Warning: Improper firmware of radio module can lead to loss IMEI Backup the original file before replacing it!

For devices on Qualcomm Snapdragon (most Xiaomi), you can use the QPST utility to fine-tune modem settings, but it requires an unlocked bootloader and experience with ADB.

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Before you run your radio, check the version in the engineering menu (#4636## → Phone Information). If the current version is newer than the downloaded one, no update is required.

4. Physical methods of signal amplification

If the software methods didn't work, the problem could be the hardware, the weak antenna, the bad contacts, or the shielding of the case.

✅ Check the integrity of the antenna tracks. On Xiaomi, antennas are usually located on the sides of the body (see the plastic inserts on the metal case). If the smartphone fell or was exposed to moisture, the contacts could oxidize. Disassemble the device (or contact the service) and check:

• 🔧 Status. FPC-plumes connecting antennas to the motherboard.
• 🔧 Corrosion on the antenna module contacts (frequent problem after moisture is ingested).
• 🔧 Integrity RF-cables (thin wires from antennas to modem).

✅ Use an external antenna. Some Xiaomi models (e.g. Mi Max 3 or Mi Max) POCO M3 Pro) support connection of an external antenna via the connector TS-9 or SMA. It's gonna take a while:

• 📡 Passive antenna (e.g., passive antenna, 4G LTE Antenna with AliExpress).
• 📡 Adapter for connecting to a smartphone (if there is no built-in connector, you can solder to antenna contacts on the board).
• 📡 Signal amplifier (repiter) for very weak coating areas.

✅ Remove covers and metal accessories. Metal bumpers, magnetic holders or metal-enabled covers can shield the signal. Testing has shown that even wireless charging can sometimes degrade network reception due to interference from the coil.

5. Alternative solutions: Wi-Fi Calling and operator switching

If you can’t improve your cellular signal, consider alternative ways to call and use the Internet:

📞 Wi-Fi Calling (Wi-Fi calls) is available on most Xiaomi devices MIUI 12+. To turn on:

1. Go to Settings. → SIM-maps and mobile networks → [Yours. SIM] → Wi-Fi Calling.
2. Activate the function and follow the operator’s instructions (confirmation via SMS may be required).

Wi-Fi Calling uses the Internet for voice calls, which saves in areas with poor coverage, but with weak Wi-Fi, the quality of communication can deteriorate.

🔄 Change of operator or tariff. Some operators work better in certain regions:

• 🏙️ In the cities of MegaFon and MTS often lead in coverage 4G/5G.
• 🌾 In rural areas, Tele2 or Yota may offer a more stable signal in the 800 MHz band (B20).
• 🌐 For travel abroad, roaming rates are more profitable (for example, Beeline. Travel).

📶 Use network monitoring applications. Network Cell Info Lite or NetMonster shows the current tower, signal strength (in dBm) and range used. This will help determine where the connection is best and choose the optimal location for calls.

6 Advanced Methods: IMEI Change and Firmware Modification

If all previous methods have failed, you can try changing the firmware region or IMEI. These are risky methods, but sometimes they help unlock additional frequency bands.

🔧 Some Xiaomi models (e.g. Redmi Note 9 Pro) have different firmware versions for India, Europe and China (EEA) They're often better optimized for local operators:

1. Unlock the bootloader through the Mi Unlock Tool.
2. Install custom recovery (TWRP).
3. Scroll fastboot-rom for the desired region (download at xiaomifirmwareupdater.com).

🔧 Change of change IMEI. On some Xiaomi (especially Chinese versions) IMEI It can be blocked to work with local operators. IMEI If you do decide to use clean, it may improve compatibility, but it violates the laws of many countries (including Russia) and voids the warranty. IMEI through the engineering menu:

Enter the dialer:
##36446337## → Check the current IMEI
##7465625## → Test SIM-Locks

⚠️ Attention: Change IMEI 13.3 of the Administrative Code of the Russian Federation, we do not recommend this method and we give it only for familiarization.

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Before any firmware or IMEI modifications, backup your data via Mi Cloud or TWRP. Recovering the original IMEI may require contacting a service center.

7. When to contact the service center?

If none of the methods worked, the problem could be a hardware malfunction:

• 🔌 The communication module (Qualcomm or Mediatek modem) is damaged).
• 📡 Breaking of antenna tracks after falling or getting moisture.
• 🔋 Failure of the power controller responsible for powering the modem.

The cost of repairing the communication module in Xiaomi varies from 1,500 to 5,000 rubles, depending on the model.

• Redmi 9A - Replacement of antenna ~1 800 rubles.
• POCO X3 Pro - modem replacement ~3500 rubles.
• Mi 11 – diagnostics + repair ~ 4,200 rubles.

Before the service visit:

1. Make a reset to factory settings (Settings → About Phone → Resetting).
2. Check your smartphone with another SIM-card (better than the same operator).
3. Check if the data will be saved after the repair (sometimes a complete reset is required).

FAQ: Frequent questions about signal improvement on Xiaomi