Field Test 4G Mobile Signal Strength

Want to know if Outdoor 4G Router works for you? Do a simple field test on your mobile phone by using your mobile phone to check the signal quality outside your house.

To get more accurate data, please disable the Wi-Fi connection on your mobile phone. You can read signal bars followed by carrier name and network symbol.

Mobile Network Types

You can see what network type you’re connecting to (2G, 3G, 4G, LTE, etc.). Take note of signal bars and the symbol in the status bar of your mobile phone and compare it with the below chart.

The 4G routers can connect to 2G, 3G, and 4G mobile networks. However, to get a fast speed and stable internet connection, we should input a robust 4G LTE signal for the router. For example, if the mobile symbol is G/E/3G/H, the 4G router can not work as well as it’s designed to. Please walk around to find another location that has the minimum 2-bar LTE signal reception.

Symbol Mobile Networks Voice Call Internet Speed Email & Notification Video
4G (LTE) Fourth generation or Long term evolution
also known as LTE or WiMax
Yes 100Mbits/s+ Yes Yes
3G Third Generation
also known as UMTS / WCDMA / CDMA2000
Yes 2Mbits/s Yes Yes
(General Packet Radio Service)
Yes 50Kbits/s Yes No
(Enhanced Data GSM Evolution)
Yes 100Kbits/s Yes No
(High-Speed Packet Access)
Yes 10-100Mbits/s Yes Yes
No Symbol If signal bars get more than 1 bar
you can use voice call
N/A No No No

Mobile Signal Quality

To measure mobile phone’s signal reception in exact decibels instead of bars or dots, you can follow guidance to enable the Field Test Mode in mobile phones.

Decibel signal strengths will be negative 2~3 digits.  Unit of measurement is dBm. If your phone show a number such as 98, the actual signal strength is -98dB. The closer the number is to zero, the better the reception, so -90dB is a stronger signal than -100dB.

The numerical value of 2G / 3G / 4G H+ networks is RSSI standard which is Received Signal Strength Indicator. LTE network is RSRP standard which is Reference Signal Receive Power.

Mobile Signal Quality Chart

Field Test Mode on iPhone

  1. Go into the Phone app and switch to the Keypad. Dial *3001#12345#* and press Call button to launch the Field Test Mode on your iPhone. 
  2. In the iOS 14.8, tap the menu button on the top right corner.
  3. Click Serving Cell Info, then nevigate to Freq_band_ind. That is the LTE frequency band.
  4. Return to the previous page and tap on Rach Attempt and find the RSRP value on the first row.

Field Test on iOS 14.8

  1. Go into the Phone app and switch to the Keypad. Dial *3001#12345#* and press Call button to launch the Field Test Mode on your iphone. 
  2. In the iOS 13.3, tap on LTE > Serving Cell Info. Freq_band_ind is the LTE frequency band.
  3. Tap on Serving Cell Mass > Rsrp0 to check the LTE signal strength.

Field Test on iOS 13.3

  1. Go into the Phone app and switch to the Keypad. Dial *3001#12345#* and press Call button to launch the Field Test Mode on your iPhone. 
  2. In iOS 12, tap on Serving Cell Measurements to check the strength and band.

Field Test on iOS 12

Test Signals on Android Phone

Android Phone App - Network Cell Info Lite
  1. On Google Play store, search for Network Cell Info Lite and install it.
  2. Make sure inserted a workable SIM card in the phone, turn on GPS on the phone, and open the above newly installed APP.
  3. Tap on Raw to check the frequency band and signal strength.
Network Cell Info APP for Test Signals

Go to Settings > About Phone > Status > SIM Status and numerical signal strength will be available on either network or status which depends on the model of phone.

You can also use apps to show signal strength in decibels in Android phones.

Check Signals on 4G Router

When the 4G router is turned on with a workable SIM card, log in the 4G router admin, we can find the modem device information on the right column of the front page.

The mobile modem model, IMEI number, and connection status are listed in the device column. Click the “Reacquire” button we can get the updated modem information.

Since EV3117 firmware version, the mobile protocol has switched to “MobileData”. The “Signal Strength” changed to a percentage number for easier understanding.

To read the exact decimal signal strength, please use the below MMCLI commands on SSH terminal.

Outdoor 4G Router Modem Device info with signal quality


After logging in the router admin, go to System > Terminal. Enter the router user name root and router password, which does not shows up when inputting, to enter the command-line interface on the web browser.

Verify Modem Sequence
mmcli -L

To list the current modem.

If the router has not set up a 4G connection, the guardian module will automatically restart the modem. The modem will disappear from the list temporarily. We can use the below command to monitor the modems.

mmcli -M

Press Ctr+Z on the keyboard to exit the monitor status.

4G MobileData - Verify Modem Sequence Number
Check Signal Strength
mmcli -m 0 --signal-setup=30

Set the signal refresh rate to 30 seconds. You can change the interval to 20 seconds by replacing 30 to 20.

mmcli -m 0 --signal-get

To list the decimal signal strength of the currently connecting network.

4G Modem Manager Signal Strength

Insert a SIM card, turn on the power, and log in the 4G router admin. On the right column of the front page, you can check the modem device information, including mobile network band and signal strength.

Click the Reacquire button to get the updated signal strength information.

  • The network band is the current mobile network connecting to.
  • RSRP value is the signal strength. When connecting to 3G WCDMA or UMTS network, please check the RSSI value.

Since the mobile connection is in the first priority, on the first boot, the device information will take a few minutes to show completely.


After logging in the router admin, go to System > Terminal. Enter the router user name root and router password, which does not shows up when inputting, to enter the command-line interface on the web browser.

Verify SIM Registration

Enter gcom command to verify the SIM card installation and registration.

If it shows SIM error, please check if the SIM card is workable; if the SIM card inserts in the correct slot, the default setting is used SIM1 slot.

If the Registration is Failed, please check if the SIM card is already activated.

Check Signal Strength

Enter the below uqmi command to check the instant mobile network type and signal strength (unit is dBm).

uqmi -d /dev/cdc-wdm0 –get-signal-info

The above uqmi command does not work under the 4G-PPP protocol.

Signal bars VS decibel signal strength

Signal Bars iPhone Mobile Nokia Phone
5 > -85 dBm > -91 dBm
4 -85 ~ -90 dBm -91 ~ -101 dBm
3 -90 ~ -95 dBm -101 ~ -103 dBm
2 -95 ~ -100 dBm -103 ~ -107 dBm
1 -100 ~ -105 dBm -107 ~ -113 dBm
0 < -105 dBm < -113 dBm

4G LTE Bands and Frequencies

4G mobile phone networks has two different standards FDD LTE and TDD LTE. Both of them are used to maximize the available bandwidth.

FDD LTE uses a paired spectrum with different frequencies to transmitting (uplink) and receiving (downlink) signals simultaneously. TDD LTE uses unpaired spectrum because the working frequency for transmitting (uplink) and receiving (downlink) is exactly same.

FDD-LTE Band Uplink Downlink Band Width Duplex Spacing Guard Band
B1 1920 – 1980 MHz 2110 – 2170 MHz 60 MHz 190 MHz 130 MHz
B2 1850 – 1910 MHz 1930 – 1990 MHz 60 MHz 80 MHz 20 MHz
B3 1710 – 1785 MHz 1805 – 1880 MHz 75 MHz 95 MHz 20 MHz
B4 1710 – 1755 MHz 2110 – 2155 MHz 45 MHz 400 MHz 355 MHz
B5 824 – 849 MHz 869 – 894 MHz 25 MHz 45 MHz 20 MHz
B6 830 – 840 MHz 875 – 885 MHz 10 MHz 35 MHz 25 MHz
B7 2500 – 2570 MHz 2620 – 2690 MHz 70 MHz 120 MHz 50 MHz
B8 880 – 915 MHz 925 – 960 MHz 35 MHz 45 MHz 10 MHz
B9 1749.9 – 1784.9 MHz 1844.9 – 1879.9 MHz 35 MHz 95 MHz 60 MHz
B10 1710 – 1770 MHz 2110 – 2170 MHz 60 MHz 400 MHz 340 MHz
B11 1427.9 – 1452.9 MHz 1475.9 – 1500.9 MHz 20 MHz 48 MHz 28 MHz
B12 698 – 716 MHz 728 – 746 MHz 18 MHz 30 MHz 12 MHz
B13 777 – 787 MHz 746 – 756 MHz 10 MHz – 31 MHz 41 MHz
B14 788 – 798 MHz 758 – 768 MHz 10 MHz – 30 MHz 40 MHz
B15 1900 – 1920 MHz 2600 – 2620 MHz 20 MHz 700 MHz 680 MHz
B16 2010 – 2025 MHz 2585 – 2600 MHz 15 MHz 575 MHz 560 MHz
B17 704 – 716 MHz 734 – 746 MHz 12 MHz 30 MHz 18 MHz
B18 815 – 830 MHz 860 – 875 MHz 15 MHz 45 MHz 30 MHz
B19 830 – 845 MHz 875 – 890 MHz 15 MHz 45 MHz 30 MHz
B20 832 – 862 MHz 791 – 821 MHz 30 MHz – 41 MHz 71 MHz
B21 1447.9 – 1462.9 MHz 1495.9 – 1510.9 MHz 15 MHz 48 MHz 33 MHz
B22 3410 – 3500 MHz 3510 – 3600 MHz 90 MHz 100 MHz 10 MHz
B23 2000 – 2020 MHz 2180 – 2200 MHz 20 MHz 180 MHz 160 MHz
B24 1625.5 – 1660.5 MHz 1525 – 1559 MHz 34 MHz – 101.5 MHz 135.5 MHz
B25 1850 – 1915 MHz 1930 – 1995 MHz 65 MHz 80 MHz 15 MHz
B26 814 – 849 MHz 859 – 894 MHz 35 MHz 45 MHz 10 MHz
B27 807 – 824 MHz 852 – 869 MHz 17 MHz 45 MHz 28 MHz
B28 703 – 748 MHz 758 – 803 MHz 45 MHz 55 MHz 10 MHz
B29 N/A 717 – 728 MHz 11 MHz N/A N/A
B30 2305 – 2315 MHz 2350 – 2360 MHz 10 MHz 45 MHz 35 MHz
B31 452.5 – 457.5 MHz 462.5 – 467.5 MHz 5 MHz 10 MHz 5 MHz
B66 1710 – 1780 MHz 2110 – 2200 MHz 90/70 MHz 420 MHz 330 MHz
B71 663 – 698 MHz 617 – 652 MHz 35 MHz -46 MHz 11 MHz
TDD-LTE Band Frequency Band Width
B33 1900 – 1920 MHz 20 MHz
B34 2010 – 2025 MHz 15 MHz
B35 1850 – 1910 MHz 60 MHz
B36 1930 – 1990 MHz 60 MHz
B37 1910 – 1930 MHz 20 MHz
B38 2570 – 2620 MHz 50 MHz
B39 1880 – 1920 MHz 40 MHz
B40 2300 – 2400 MHz 100 MHz
B41 2496 – 2690 MHz 194 MHz
B42 3400 – 3600 MHz 200 MHz
B43 3600 – 3800 MHz 200 MHz
B44 703 – 803 MHz 100 MHz

14 thoughts on “Field Test 4G Mobile Signal Strength

  1. Jean-Charles Gfeller says:

    Hi, this command line
    mmcli -m 0 –signal-get
    doesn-t give me info about the signal as in the screenshot.
    It return only general informations about the router.
    I-ve got a double directional antenna, and I would like to find to best orientation. But no matter what direction I-m pointing it-s always the same signal strength showing in the “modem device information on the right column of the front page”

  2. Adrien Boudin says:

    I am in the rare case where I need to lock the 4g router on a specific band to achieve a stable connection. But I dont understand how to get the list of the bands that the modem received to be able to lock the modem to one of these bands.

  3. Jamie Olejnik says:

    I have the issue. Used mmcli -L command to confirm that using Modem 2.

    I then ran the command (which differs from your tutorial and the screenshot) mmcli -m 2 –signal-get
    I get the error: modem had no extended signal capabilities

    The Device status on the Status Overview page does not show any detail on the SIM connection apart the operator. It says SIM status – disabled. I am unable to see any signal strength details inc. which technology i.e. 4G LTE I am using…..

    Currently using firmware version EV3121. Router model EZR33.

  4. Gabriele Domenichini says:

    I cannot connect anymore. I have tried the commands but on:
    mmcli -m 0 –signal-get
    I get:
    error: modem has no extended signal capabilities

    Also, when I press Ctrl+Z it says:
    ^Z[1]+ Stopped mmcli -M

    which I’m not sure it’s correct. Normally to stop something I do Ctrl+C. Ctrl+Z stops it. Are we sure is this what we want?

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