How to Do a Site Survey

If you receive a weak signal on your phone or mobile broadband inside a building and you experience dropped calls or slow data speeds, the solution is to install a cellular signal boosting system. However, the exact equipment you’ll need will greatly depend on the signal outside of your building. It’s important to do a site survey to find out exactly how weak your signal is outside and the size of the area you need to cover inside. This will tell you what type of equipment will work best for you.

Before getting started, it helps to know a little bit about how cellular signal boosting systems work. In short, they’re made up of an antenna that receives the signal outside, an amplifier that increases the signal strength, and an inside antenna to redistribute the amplified signal. This lets you receive a stronger signal on your phone, tablet or laptop.

Typically, to conduct a site survey, you’ll use the device that you’re aiming to improve the signal for. If you need to improve the signal on a phone or tablet, you’ll use that device. If you need a better mobile broadband signal for your laptop, you’ll connect your mobile broadband modem (or “aircard”) to your laptop and you’ll measure the signal strength on your laptop.

Can I Do a Site Survey Myself?

The short answer is yes. It requires taking a few simple readings, with either your phone or laptop.

Measuring the Signal Strength in Decibels (dB)

To do a site survey, you need to be able to accurately measure the signal strength at various locations. While “bars” of signal can give you a rough measurement, it’s more accurate to measure the signal in Decibels or dB.

To process for viewing the current signal strength in decibels varies by phone. See our Field Test Mode guide page for more information.

Decibels are expressed as a negative number, like -70 dB. The closer the number is to 0, the stronger the signal. For example, -70 dB is a stronger signal than -90 dB. If your phone or computer shows a positive number, just add a negative sign to it, so 70 would really be -70 dB.

Conducting a Site Survey with a Cell Phone or Mobile Broadband Modem

There are two main goals when conducting a Site Survey. First, you want to find the location outside of your home or office with the strongest signal. This will often be on the roof of the building since the higher up you go, the fewer obstacles exist between you and the cell tower. The second goal is to determine what area needs to be covered inside your home or office. In some buildings, only a lower level may need a signal boost. Other buildings will require the entire inside area to receive a stronger signal.

To determine the signal strength that you have outside of your building, you’ll need to take some measurements in the places that you could mount your outside antenna. Generally, you want to mount the outside antenna as high as possible so that it gets a strong signal and doesn’t interfere with the inside system. Therefore, try to take a few decibel measurements on the roof of the building to get the most accurate readings.

Next, determine in square footage of the area inside where you need a stronger signal.

Interpreting the Results of Your Site Survey

The first thing to check is to make sure that you have an existing signal in at least one point outside. If you didn’t receive a signal in any of your outside measurements, there isn’t enough signal available to amplify and a cell phone signal booster system won’t work in your situation.

If your outside signal is weaker than -90 dB, we strongly recommend using a directional yagi-type outside antenna to ensure the system has a strong enough signal to cover your inside area. In general, unless you need to support multiple carriers, we always recommend using a directional antenna.

Choosing the best signal booster amplifier for your situation is more complicated. The advertised coverage area is under ideal conditions, so if you have a weaker signal, you’ll get a smaller coverage area.

Once you’ve gathered all of this information, contact the UberSignal team at (800) 590-3564 and one of our technical support specialists will be able to help you interpret the results of your Site Survey and recommend the best signal booster system for you.