The situation when a smartphone shows a full scale of divisions, but Internet pages do not load or voice communication is interrupted, is familiar to every user. Visual indicators in Android are often conditional and do not reflect the real picture of radio quality. To understand the true state of affairs, you need to refer to the exact digital values that are hidden in the system settings of the device.
To diagnose communication problems, it is important to understand that operators use different frequencies and data transmission standards. Signal level is not just the number of “sticks” on the screen, but a complex parameter that depends on the distance to the tower, obstacles and network congestion. Knowing how to measure this indicator accurately, you can determine whether the problem lies in your smartphone or the operator's coverage.
In this article we will analyze professional diagnostic methods available to the average user without root access. You will learn to read technical network parameters, use the engineering menu and third-party monitoring software. This knowledge will allow you to make informed decisions about changing locations, operators, or even phone models to ensure stable communications.
⚠️ Attention: Menu interfaces and available functions may vary depending on the Android version, manufacturer's shell (MIUI, One UI, ColorOS) and processor model. If one method does not work, try the next method from the list.
Understanding units of measurement of communication quality
Before moving on to measurements, you need to understand the terms you will encounter. The main indicator is RSRP (Reference Signal Received Power) - the power level of the received signal. It is measured in decibel milliwatts (dBm) and is always negative. The closer the number is to zero, the better the quality of communication.
The second important parameter is SINR (Signal-to-Interference-plus-Noise Ratio), which shows the ratio of the useful signal to noise. A high SINR means the signal is clear and is not being drowned out by interference from other towers or electronic devices. Even with good RSRP, low SINR can lead to low Internet speed.
For 3G networks (UMTS/HSPA), a parameter is used RSCP, which is analogous to RSRP, but for older standards. Understanding the difference between these values is critical, since the standards for 2G, 3G, 4G and 5G networks are significantly different. Below is a table to help you interpret the obtained values.
| Parameter | Excellent signal | Average signal | Bad signal | No connection |
|---|---|---|---|---|
| RSRP (4G/5G) | -75 dBm and above | -95... -85 dBm | -110... -100 dBm | Below -120 dBm |
| SINR (4G/5G) | More than 20 dB | 10... 15 dB | 0... 5 dB | Negative values |
| RSCP (3G) | -65 dBm and above | -85... -75 dBm | -100... -90 dBm | Below -115 dBm |
Please note that the values are always negative, since the dBm logarithmic scale starts from 1 milliwatt. A decrease in signal level by 3 dBm means a halving of power. Therefore, the difference between -80 dBm and -90 dBm is colossal, although visually on the phone scale it can be displayed the same.
Using secret codes to enter the menu
The fastest way to access technical information is to use USSD commands or engineering codes. These combinations allow you to enter a hidden testing menu, where detailed data about the current connection is displayed. Enter the code in the dialing field and the menu will open automatically.
The most universal code for devices based on MediaTek chipsets and many others is ##4636##. After entering the last digit (#), the "Check" or "Testing" menu should open itself. If this does not happen, your smartphone manufacturer may have blocked this access or changed the code.
For Samsung devices, a code is often used #0011#, which opens a service menu with detailed information about the status of the SIM card and signal strength. Codes may work on some Xiaomi and Huawei models ##6484## or ##2846579##* respectively.
What to do if the codes do not work?
If none of the codes open the menu, try installing the "QuickShortcutMaker" application from the Play Store. It allows you to find hidden system activities, including engineering menus that are blocked for direct dialing. Also, access may be denied on re-flashed devices or in some regions.
Inside the testing menu, select "Phone Information". Here you will see the current network type, SIM card status and, most importantly, the "Refresh" button or automatically updated signal strength data. This is where the very ones dBmthat are needed for accurate diagnosis are displayed.
Professional applications for network monitoring
If the system menus seem too complex or inaccessible, specialized applications come to the rescue. They not only read the data, but also visualize it in a convenient form, build graphs and help you find the place with the best reception. Such utilities are often more useful than standard indicators.
One of the most popular tools is Network Cell Info Lite. This application displays information as a widget on the desktop or in a floating window. It shows RSRP, RSRQ, SINR and connection type (LTE, H+, 3G) in real time. The interface may seem overloaded, but it contains all the necessary information.
- 📶 Network Cell Info Lite - a powerful tool with widgets, tower maps and detailed statistics, ideal for finding the place with the best signal.
- 📡 Signal Check Pro - an application that specializes in accurately measuring signal strength and speed, with the ability to calibrate sensors.
- 📊 CellMapper - allows you to do more than just see signal, but also build coverage maps by sending data about towers to a common database (requires registration).
Another great option is G-NetTrack. This is a professional tool that is often used by communications engineers. It can record logs of signal changes over time and on a map. If you need to prove poor coverage to the operator or find the “sweet spot” in the house to install a router, this application will be indispensable.
When using monitor applications, turn on the “Full Screen” mode or widget to see signal changes in real time as you move around the apartment. This way you will quickly find a stable reception area.
Analysis of indicators through the developer settings
In Android there is a hidden section for developers, which can also provide useful information, although less detailed than the engineering menu. To activate this section, you need to go to “Settings” → “About phone” and quickly click on “Build number” 7 times.
After activation, the “For Developers” item will appear in the settings menu. Inside it you can find network-related options, such as “Always turn on mobile data” or selecting your preferred network type. However, for directly measuring the signal level in dBm, this section is less suitable than codes or applications.
However, here you can forcefully switch the network mode. For example, if you have unstable 4G but good 3G, you can select "3G Only" under "Preferred Network Type". This temporary solution will help maintain communication in an area of uncertain reception, sacrificing speed for the sake of stability of voice calls.
☑️ Checking network settings
Factors influencing the quality of reception
Understanding what exactly degrades the signal helps to more effectively deal with the problem. Wall materials, electromagnetic interference, and even weather can affect call quality. Metallized windows, thick concrete floors and mirror surfaces are serious obstacles to radio waves.
It is also worth considering the load on the tower. In the evening, when subscriber traffic is at its maximum, the speed may drop even with a good signal level (RSRP), but low SINR. This is due to the fact that the channel resource is divided among a large number of users.
- 🏢 Building materials —energy-saving glass and fittings in walls can screen up to 90% of the signal.
- 🌳 Terrain —hills, forests and dense buildings create “dead zones” and signal reflections.
- 📱 Antenna design —in modern smartphones, antennas are built into the body, and covering them with your hand (the “death grip” effect) can reduce the level of reception.
⚠️ Attention: Do not use magnetic phone holders in the antenna area. Magnets can create interference and reduce the efficiency of the antenna module, which will lead to a decrease in the speed and quality of communication.
Practical tips for improving the signal
If measurements show a low signal level, there are several ways to try to improve it without buying expensive equipment. First, try rebooting the device - this will force modem to reconnect to the nearest and less busy tower.
Remove the case from your phone if it contains metal elements or is too thick. Sometimes simply changing the position of the phone or moving half a meter to the side can give an increase of 3-5 dBm, which will significantly affect the stability of the connection.
As a last resort, if you are in the “borderline” reception area, turn on airplane mode for 10-15 seconds and turn it off. This forcibly initiates a network search and can help to lock onto a signal if the module was previously stuck trying to maintain a weak connection.
The most effective way to improve the signal indoors is to find a point near the window, directed towards the operator's tower, and fix the phone there.
Frequently asked questions (FAQ)
Is it true that stickers on the antenna improve the signal?
No, that's a myth. Stickers with "amplifiers" do not contain active elements and cannot amplify the radio signal. At best, they are useless, at worst, they create additional interference.
Why does the signal level fluctuate?
Signal surges (ping-pong effect) often occur at the border of the coverage of two towers. The phone constantly switches between them, trying to find the best signal, which leads to an unstable connection.
Does the SIM card affect the signal level?
Yes, an old or damaged SIM card may have poor contact with the module, which leads to reading errors and a drop in the signal level. Also, older cards may not support all frequencies of modern 4G/5G networks.
Can a virus worsen communications?
Malware can load a data channel in the background, creating the illusion of poor communication due to low speed, but viruses cannot change the physical signal level (dBm).
Is it worth buying an external antenna amplifier?
This only makes sense in country houses with a very weak signal. For a city apartment, it is often enough to place the router or phone correctly. Before purchasing, be sure to measure the signal level.