how to check your mobile signal strength accurately field test mode

How to Check Your Mobile Signal Strength Accurately – Field Test Mode

People most often measure or identify their mobile signal strength based on the signal bar display on their mobile phone. But that’s not the real test of measuring the mobile signal strength accurately. So, now the question is how to check your mobile signal strength accurately. So that you can decide if you want to buy a mobile signal booster to enhance your mobile signal strength. The answer to this is the “Field Test Mode”.

In this post, we will discuss the Field Test Mode. And how to use it to accurately measure your mobile signal strength. Remember that the mobile signal strength could be different inside and outside a building, distance from the cell tower, etc.

Choosing Mobile Signal Booster Based on the Signal Strength

One of the first steps to selecting the right mobile signal booster for your home or office is to determine how strong the outside signal is. When most people talk about cell phone signal strength, they refer to “bars” in reference to the signal strength bar indicator on the phone. While signal bars are an easy way to measure mobile signal strength, it turns out that it’s not a very accurate way of testing mobile signal strength.

While many phones show the signal strength on a 5-bar scale, some phones only have 4 bars while others have 8. Even among phones with the same number of bars, there’s no standardization, so the strength of a 4 bar signal on one phone can be very different than a 4 bar signal on another phone.

So it is evident that signal bars aren’t very granular. For instance, say 2 or 3 bars of the signal is not being very specific in terms of measuring mobile signal strength.

You know when experts measure cell phone signal strength, they measure the signal in decibels. Decibels are a logarithmic unit of measuring signal strength and are very precise making them ideal for performing a signal test of just how strong signals you’re currently receiving.

Field Test Mode on iOS and Android Devices

Most phones have a built-in setting known as “Field Test Mode.” This Field Test Mode can show you useful information about your phone, including the signal strength in decibels. But, before we actually explain how to use the Field Test Mode, here are a few things to keep in mind about taking mobile signal readings in decibels:

  • Any signal readings you take are only valid for the phone’s individual carrier: To get readings from other carriers, you’ll need phones from each carrier. For instance, if there are four different cellular service providers in your area you won’t get the signal strength of each one through Field Test Mode. You will only get the signal strength of the cellular carrier you are using. For other carriers, you need their phone or SIM cards.
  • Keep track of the network (2G, 3G, 4G, LTE, etc.): LTE readings are sometimes measured differently from previous generation networks like 2G, 3G, and 4G. So without knowing if a signal is from an LTE network or a previous network, it’s impossible to interpret the results.

iPhone Field Test Mode

The iPhone has a hidden built-in Field Test Mode app. To access it, follow these steps:

  1. Go into Settings > WiFi and turn WiFi Off.
    This will enable you to see what network you’re connected to (2G, 3G, 4G, LTE, etc).
  2. For iOS 9.3 and above: Go into Settings > Cellular > Cellular Data Options > Enable LTE and turn LTE to Off. For iOS 9.2 and below: Go into Settings > Cellular > Enable LTE and turn LTE to Off. LTE readings can be very different from previous networks so to best interpret the results, we ideally want signal readings from a previous generation network. You can also repeat the site survey with LTE enabled, just be sure to keep track of which readings for different generation networks.
  3. Go to Phone Keypad. Dial *3001#12345#* and press the Call button: This will launch the Field Test Mode app and where the bars/dots were in the top left corner of the screen, you’ll now see a negative number. The negative number is the decibel signal strength reading and should be followed by the carrier name and then the network type.

If you see “‹ Back to Phone” in the top left corner

In iOS 9+, Apple updated the Field Test Mode app so that instead of showing the decibel signal strength in the top left corner, it now says “Back to Phone”. To take decibel signal readings on an iOS9 or newer iPhone, follow the steps below under the heading Always show Decibels instead of Dots.

When taking signal readings, move to the location where you want to take the reading, wait for 30 to 60 seconds for the signal readings to catch up, and then record the signal strength, carrier, and network type (2G, 3G, 4G, LTE, etc.).

To exit and return your iPhone to normal status, all you need to do is hit the Home button. Also, remember to go back into Settings and enable WiFi and Cellular LTE. This mode is available on any iPhone running iOS 4.1 and all later versions.

Field Test Mode in iOS 13 & iOS 12 and iPhone 11, XS, XR, X

Check this to activate and use Field Test Mode in iOS 13 & iOS 12

Android Field Test Mode

Accessing Field test mode on Android phones is also very simple. You simply need to find your way to “Settings” > “About Phone”, and your numerical signal strength (in decibel) will be available under either “Network” or “Status”, depending on the model your phone. There’s usually another option near the signal strength that says the Network Type.

There are also apps you can download from the Google Play Store that will show you the signal strength in decibels along with other information. Go to the App Store and search for “cell signal” to find available apps for your device. Download one which is compatible with your device.

When taking signal readings, move to the location where you want to take the reading, wait for 30 to 60 seconds for the signal readings to catch up, and then record the signal strength, carrier, and network type (2G, 3G, 4G, LTE, etc.).

This way you will be able to correctly record the signal strength at different places in and around your house or office.

What is it Used For?

The most common use of Field Test Mode is to conduct a special kind of field signal test known as a site survey or Floor Plan Analysis. If you find yourself living or working in an area with weak signal strength on your mobile phone, and you want to boost your signal, performing a site survey will be useful before you choose a mobile signal booster to boost your signal strength. Remember, that mobile signal boosters are also known as the cell phone signal boosters, network repeaters, signal amplifiers, signal repeaters, GSM Signal Booster, Boost Box, etc.,

The site survey involves taking several accurate readings of signal strength in and around your building, in order to calculate whether a GSM Signal Booster will help, and if so, what sort of equipment will be necessary.

Field Test mode is a very useful tool in such a situation – switching from unreliable signal bars to a precise numerical value is essential if you want to quantitatively assess your Smartphone’s signal strength in different places.

Although a site survey field test is a multi-step process, it is however very simple, and if you follow the steps we have explained you can easily measure the signal strength in and around your home or office, using the field test mode on your phone.

How to Decipher the Numbers (Decibel)?

When connected to a 2G, 3G, or 4G H+ network, this numerical value is known as RSSI (Received Signal Strength Indicator) and is a method of measuring wireless signals. LTE networks, on the other hand, are typically measured in RSRP (Reference Signal Received Power), which is why LTE readings are sometimes very different from previous generation signal readings.

Decibel signal strengths are generally double or triple digits, and it is marked in negative. Some phones don’t show a negative sign so if your phone shows just a number such as 90, the signal strength is really -89. The closer the number is to zero, the better the reception, so -79 is a stronger signal than -89.

The unit of measurement is the decibel (dB), which is a measure of the power of a cellular signal. Similar to the volume of a stereo, the numerical value is really telling you exactly how strong your phone is receiving the signal from your provider’s cellular network.

The decibel scale is not linear – an increase of 3 dB corresponds to a signal that is twice as strong while a 10 dB increase corresponds to a 10 times increase in signal strength. So an RSSI value of -60 is actually ten times stronger than an RSSI of -70, for example.

Having an accurate reading of your Received Signal Strength is crucial when you’re assessing an area with the purpose of installing a mobile phone signal booster. Being able to see exactly how strong your mobile signal is, outside and inside your building, is essential in finding out how a mobile signal booster can improve your reception.

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