Free Shipping on Orders Over $99 - Learn More

Cell Phone Signal Boosters: A Complete Buyer’s Guide

Cell Phone Signal Boosters: A Complete Buyer’s Guide

Jeff Morin |

Struggling with dropped calls, sluggish data, or dead zones in your home, office, or vehicle? You’re not alone, and the good news is: there’s a solution. Whether you're working from home, driving through remote areas, or managing a business, a cell phone signal booster can drastically improve your connectivity.

In this guide, we’re breaking down everything you need to know to fix your cell signal woes for good. From understanding why your signal is so weak to choosing the right booster for your space, this buyer’s guide will take you through every step. We’ll cover how these boosters work, the best options for different situations, and answer the key questions you didn’t even know you had.

Ready to get crystal-clear calls and faster data, no matter where you are? Let’s dive in!

1. The Causes of Bad Cell Signal

Before we go into the specifics of how cell phone boosters work, we need to cover the reasons why you’re experiencing bad cell phone signal to begin with.

Common Causes

There are several factors that contribute to poor cell phone signal:

  • Distance from Cell Towers: The farther you are from a cell tower, the weaker the signal. This is especially prevalent in rural areas.
  • Obstacles in the Way: Physical barriers like buildings, hills, and trees can obstruct signals. Weather conditions, such as heavy rain or snow, can also temporarily affect signal quality.
  • Construction Materials: Materials like concrete, brick, and metal can hinder signal penetration. If you notice a drop in signal strength when entering a building, construction materials are likely to blame.
  • Network Congestion: During peak usage times, such as rush hour, too many users on the same network can lead to decreased performance. A booster can help by targeting less congested towers that may be further away.

We'll cover these in more depth below.

Distance from the cell towers

Distance from the Cell Tower

Cellular signal is broadcast from towers that are installed by your carrier (AT&T, Verizon, etc.). The closer you are to a tower, the stronger the cell signal is going to be. As you move further away from the tower, the signal becomes weaker, which we call attenuation, until at some point it’s too weak to hold a call or transfer data.

How distance from the cell tower affects signal strength

Being too far away from a cell tower is the most common reason for weak cell signal, and the one you’ll often experience if you live or travel in very rural areas.

Terrain

Terrain and Obstacles in the Way

The second cause of poor or erratic cell signal is the presence of obstacles between you and the nearest cell tower, like a mountain, hill, or building. You may also experience this signal problem if you’re at the bottom of a valley or underground and don’t have line of sight to a nearby tower.

Signal is not usually able to penetrate through large obstacles, so it's not able to reach you. The cell signal may bounce off of other hills or buildings and reach you through reflection, in which case you’ll notice that your signal is weaker and may fluctuate up & down, otherwise you’ll most likely end up with no signal in your location.

Construction materials

Construction Materials

The last major cause of cellular signal problems is the construction materials that make up the building or vehicle that you’re in.

Brick, block, concrete, sheet metal, and wire mesh construction materials are some well-known and obvious blockers of cell service, but things like energy-efficient window coatings, tile or metal roofs, and water fixtures can also cause major signal issues.

If you find that you have a usable cell signal outside of the building or vehicle, but it drops significantly once you step inside, then construction materials are the most likely culprit.

Network congestion

Network Congestion

Network congestion occurs when too many users are trying to access the same cell tower at the same time, particularly during peak hours like rush hour or large events. This can lead to slow data speeds, dropped calls, and an overall frustrating experience. If you find your signal quality drops when everyone is using their phones, you’re likely facing congestion.

A cell phone signal booster can help in this situation by amplifying signals from less crowded towers that might be further away. By connecting to these less congested towers, the booster can improve your overall connection, ensuring better voice calls and faster data, even during busy times.

Combinations of Causes

Unfortunately, these causes of bad cell signal frequently work in combination, so you'll find a rural warehouse with weak outside signal and sheet metal walls that completely block the signal from entering the building, or a house in a valley without a clear line of sight to the nearest cell tower, and no other nearby cell towers with which to receive a signal.

When we're looking at solutions to solve your cell phone signal issues, it's good to have an idea of what combination of causes is creating the problem that you're facing, so that the right solution can be put into place.

2. How a Cell Phone Booster Can Help

Now that we have an idea of what causes bad cell signal, it's time to look at what we can do to fix it.

First, we'll cover whether cell phone boosters really work, then discuss the basics of how a signal booster works, and finally go into more depth on the two main types of signal boosters:

Lastly, we'll cover how signal strength affects coverage and 2G, 3G, and 4G LTE networks.

Do Cell Phone Signal Boosters Work?

One of the biggest questions that we get, apart from "what is a signal booster?" is "do they really work?". This is a fair question, with all of the scammy products that have been released in the past claiming to give you better signal.

Fortunately, you don't have to take our word on whether these solutions work. The FCC and the major cellular carriers have all independently tested every signal booster that is sold on the market today and have not only approved them for use, but recommended them as a preferred solution for getting better cell signal in your home, office, or vehicle

Cell Phone Signal Booster Basics

A cell phone signal booster is a system made up of an outside antenna (called a donor antenna), a cell phone signal amplifier, one or more inside antennas, and cable to connect them all together.

The outside antenna receives cell signal from the nearby cell towers and passes it over a cable to the signal amplifier. The signal amplifier boosts the strength of the signal and then passes it over another cable to the inside antenna (or multiple antennas), which broadcast the strong cell signal to the area that needs it.

How a cell phone booster works

The signal booster also works in reverse, so when a phone call is made or data is used by a mobile device, it passes through the system, is amplified, and then broadcast to the nearby cell towers.

As long as you have some usable cell signal outside, a cell phone signal booster should be able to solve your signal problems and provide you with much better service in your home, business, or vehicle.

3. Types Of Cell Phone Signal Boosters

There are two main types of signal boosters:

  • Building signal boosters (for homes and businesses) are designed to be used in one location only and provide significantly more boosting and coverage than a vehicle signal booster.
  • Vehicle signal boosters (for cars, trucks, overland, RVs, semis, fleet and marine) are designed for use while both moving (like while driving in a car), so are less powerful than a building booster.

Let's dive into those in more depth.

Building Signal Boosters

Signal boosters for use in buildings, like a home or offices, are designed to be permanently installed in one location and provide coverage to the inside area of the building.

A building signal booster works by mounting a powerful antenna outside on the roof of the building that receives the existing outside cell signal and then passes it over a low-loss cable to a signal amplifier located inside of the building. The signal amplifier will boost the existing cell signal and then pass it over a cable to one or many internal antennas that will broadcast the boosted signal to the inside area that needs the coverage.

Building signal boosters

The booster also works in reverse, receiving the signal coming from your phone, amplifying it, and then broadcasting it to the nearby cell towers through the outside antenna.

There are different levels of building boosters, from entry-level units that cover a few feet of space to enterprise systems designed to cover vast areas with better cell phone signal. As you move up from entry-level to enterprise, the boosting power of the amplifier goes up and the quality of the components (cables, antennas, connectors) improves.

The boosting power of a building signal booster can range from around 55 decibels for entry-level boosters, all the way up to the FCC maximum of 72 decibels for amplifiers designed to boost multiple carriers in a large building. If the amplifier is designed to only boost a single carrier, then the FCC allows the maximum amplifier gain to be 100 decibels.

If you find that one signal booster kit cannot provide the necessary coverage for a large space, then multiple amplifiers and a network of antennas can be used to scale up the system and cover areas of 500,000 sq ft or more in size.

Vehicle Signal Boosters

Vehicle signal boosters are meant to be used in a car, truck, RV, or boat, and thus need to handle the constantly changing signal environment outside.

Vehicle signal boosters have an omnidirectional (sends and receives in all directions) outside antenna, usually magnetic for cars and SUVs, and permanent for trucks, RVs and boats. That antenna is connected by a cable to the signal amplifier, and then another cable is run to a small inside antenna, which broadcasts the boosted signal to the devices in the vehicle.

Vehicle signal boosters

The automatic gain control (or ability to adjust the boosting power of the amplifier) is designed to constantly adjust the strength of the amplifier based on the changing outside cell signal and maximize the amount of coverage that the booster can provide inside the vehicle.

Multi-carrier vehicle signal boosters are limited to a maximum of 50 decibels of boosting power by the FCC, so the size of the coverage area that you'll receive from a vehicle signal booster is going to be much smaller than you would receive from a booster designed for a building, but every carrier will be boosted simultaneously.

Single-carrier vehicle signal boosters have a higher limit of 65 decibels of boosting power, so you'll receive a larger coverage area inside, but will only work with the carrier that the equipment was designed for.

There is a class of vehicle signal boosters that are designed to boost the signal for a single mobile device at a time. They are lower powered and also lower cost, so they'll work well for situations where only you need your phone boosted and you have occasional dead zones outside but are not going to be the best solution for extremely rural areas or if you need to boost multiple devices.

A vehicle signal booster can make a huge difference in keeping you connected while traveling in areas with dead spots or weak cell signal, so if you spend any amount of time in a car, truck, RV, or boat, and need fast data and voice calls, then a vehicle signal booster is going to be a great option.

Signal Strength & Coverage

The most important thing to understand with cell phone signal boosters is that the strength of the outside signal has a major impact on how much coverage you're going to receive from a booster.

If you have a weak existing outside signal, you're only going to receive a small amount of coverage from a signal booster since the booster does not have much existing signal to actually boost. If the outside signal becomes stronger, then the size of the coverage area inside of the home, business, or vehicle would also grow.

If the outside cell signal remained at the same weak level, then the next best way to provide more coverage inside would be to purchase a signal booster with a more powerful amplifier.

If you're already at the maximum boosting power that the FCC allows, then the only option would be to install a second signal booster system.

For this reason, it's very important to know what your existing outside cell signal is, since that will determine what size booster you should purchase to adequately cover your inside area with boosted signal, or whether you need to install multiple systems.

2G, 3G, 4G LTE, and 5G

You've probably heard the terms 2G, 3G, 4G LTE, and 5G mentioned before and wonder how those fit in when improving your cell phone signal.

  • 2G was the second generation of cellular technology and was used for allowing people to make and receive voice calls using their cell phone, as well as send text (SMS) and picture (MMS) messages. 2G has been decommissioned, and the frequency bands repurposed for new technologies, like 4G LTE and 5G.
  • 3G was the next generation of cellular networks and allowed data to be sent over the cellular networks, in addition to voice calls and text/picture messages. It also is in the process of being decommissioned and repurposed for newer technologies.
  • 4G LTE is the cellular technology that replaced 3G and is characterized by significantly faster data rates, as well as allowing voice calls to be sent over the data network, called VoLTE. 
  • 5G is the latest cellular technology and is currently being deployed around the country. It is broken out into two versions of 5G: sub-6 GHz and millimeter-wave. Sub-6 GHz is 5G that is deployed on the existing frequency bands already in use by the carriers and can be boosted with traditional signal boosters. Millimeter-wave 5G uses very high-frequency bands for maximum data speeds and minimal latency and requires new infrastructure to be deployed, so it is currently only being released in major cities.

In almost every situation, you should choose an amplifier that boosts all five FCC-approved frequency bands to ensure you're boosting the newest and best network, no matter what frequency band it's deployed on.

4. Antennas, Cables, and Accessories Explained

Accessories

While every booster kit includes everything that you need to get started boosting signal, there are some accessories that can improve the effectiveness of your system or provide added protection against failure.

Cables

Cables are an important part of any signal booster system, as the quality and length of each cable determines how much signal will be lost between the amplifier and the antenna(s). The less signal you lose in transit, the larger the inside coverage area will be, so it's good to understand the types of cable available.

Quality and Length

In theory, you would want to use the lowest loss cable possible, but there are tradeoffs to consider.

The lower the loss of the cable, the larger it is in diameter with extra insulation and shielding, making it less flexible and harder to work with. Extremely low loss cable can be as thick as a garden hose and very difficult to run in anything but a straight line. In addition, the lower loss the cable, the more expensive it is, so long cable runs can dramatically increase the cost of a system.

Each cable type will lose a certain amount of signal over a distance, with lower loss cable obviously losing less signal. Depending on how much signal you have to begin with, a long cable run can result in all of your signal being lost, with none left when you get to the end of the cable.

It's important then to use the shortest length cable possible, and use the highest grade (lowest loss) cable that you can afford and that you're able to run from the amplifier to the antenna(s).

Types of Cables

Cable types

There are a few different types of cables that are used with signal booster systems:

  • RG174: This is the cable type that comes attached to the magnetic mount antennas included in the vehicle kits. It is the most flexible, so it can be run through a closed car door, but that also means it has the most signal loss of all of the cables we'll cover. The length for this type of cable is typically limited to about 10 ft to ensure minimal signal loss.
  • RG58: This cable has less signal loss than RG174, but is still fairly flexible. RG58 is usually limited to about 20 ft in length and is used in situations where a short but flexible cable is needed, such as cable runs in an RV or boat.
  • RG6: This is the standard coax cable that you get with cable TV. RG6 is low loss and flexible enough to run throughout a house or small business, with cable lengths kept to a maximum of 50 ft.
  • RG11: This is the lower loss, more shielded cousin of RG6. It can be used for longer cable runs than 50 ft, or for less loss during shorter cable runs. RG11 is less flexible than RG6, so it's a bit more difficult to install.
  • LMR400: This is the ultra low loss cable included with our large building signal booster kits. LMR400 is very shielded, so it is challenging to run during installation, but cable runs can be up to 100 ft in length.
  • LMR600 and above: This and any higher grade cable types have even more shielding than LMR400 and are used in professional installations for either very long cable runs or to prevent as much signal loss as possible for maximum coverage. LMR600 and above cable is typically sold in rolls and a cable expert uses special tools to terminate the desired cable length. You will typically find this cable in our commercial installations.
  • Plenum: This is a special type of cable required in plenum spaces in buildings in the United States by the National Fire Protection Association for fire safety. It is available in different grades of cable.

The cables that are included in the signal booster that you purchase will usually be sufficient for your situation, but if you have a unique floor plan, very large area, or require professional installation, then it may be worth taking a look at other cable options.

Antennas

The performance, gain, and distribution pattern of your antennas can greatly affect the performance of your booster system. We'll cover the different building antenna and mobile antenna options available, and discuss the pros and cons of each.

Building Antennas

Building antennas are designed to be permanently mounted in one location and handle a signal environment that is fairly consistent (unlike mobile antennas that are constantly in motion). These antennas are typically larger and more powerful than their mobile equivalents.

While most signal booster kits come with a single inside antenna, adding additional antenna(s) can help to increase the inside coverage area, or to craft the way that the signal is distributed in uniquely shaped areas. If you have a medium to strong outside signal and aren't getting full coverage throughout your space, then an additional antenna could be a good option for you. Please note: adding an additional antenna also requires a splitter or tapper and additional cable, so please feel free to contact us for assistance selecting the right components.

Building Outside Antenna Options

There are four main types of outside antennas for buildings, omni, directional, LPDA and parabolic grid.

Check out this video we made that covers each:

 

 

Now let's dive into each antenna in more depth: 

Omni Antenna

Omnidirectional (Omni) Antenna: The omni antenna sends and receives signals in all directions, making it a great choice when cell towers from multiple carriers are located in different directions. It works best in areas where the outside signal is medium to strong and fluctuates due to obstacles like buildings or trees. This antenna is perfect for boosting signals from multiple carriers at once and works well when the signal comes from different directions. However, because it spreads the signal in all directions, it's not as powerful as a directional antenna that focuses the signal in a single direction.

Yagi Directional Antenna

Yagi Directional Antenna: A yagi antenna is designed to target signals from a specific direction, making it ideal for situations where the nearest cell tower is far away and the outside signal is weak. It’s highly effective when boosting a signal from one or more carriers, as long as their towers are in the same general direction. This focused approach gives it better performance in weak signal areas. However, a yagi is not recommended for fluctuating signals or areas where the signal bounces off obstacles, as it can only capture signal from the direction in which it’s aimed.

LPDA Antenna

LPDA (Log-Periodic Dipole Array) Antenna: The LPDA antenna is a larger and more powerful directional antenna that offers a stronger signal and greater coverage inside your home or business. It has a narrower view of the horizon than a standard directional antenna, which means it requires more effort to aim precisely at the nearest cell tower. However, if you’re able to mount and align it correctly, the LPDA can significantly boost your signal. It’s a bit more expensive than other options, but if your budget allows, it delivers excellent performance, making it ideal for weak signal areas where you need stronger coverage.

Parabolic Grid Antenna

Parabolic Grid Antenna: The parabolic grid antenna is the most powerful option for areas with extremely weak signals, providing exceptional gain and long-range performance. It’s designed to focus on a very specific point, making it ideal for rural or remote locations where the nearest cell tower may be miles away. Its narrow beam width ensures even faint signals are captured and amplified, but it requires precise alignment for the best results. This antenna is perfect for situations where line-of-sight to the tower is essential for a reliable signal, offering the strongest possible boost for distant towers.

Building Inside Antenna Options

There are four types of inside antennas for buildings: dome, ultra-slim dome, panel, and whip:

Dome Antenna

Dome Antenna: The standard dome antenna mounts on the ceiling and spreads the signal evenly in all directions, providing solid coverage for single-floor spaces. It’s typically installed on drop ceilings or in areas where a cable can be run to the back of the antenna. Dome antennas are often used in professional installations and work best when mounted below 15 feet, though some models can perform up to 20 feet high. They are a great option for covering larger areas on one floor with reliable signal distribution.

Ultra-thin Dome

Ultra-Slim Dome Antenna: The ultra slim dome antenna offers stronger signal performance than the standard dome while maintaining a sleek, low-profile design. It delivers powerful 360-degree signal coverage across a single floor, making it perfect for spaces where both signal strength and aesthetics are priorities. This antenna is ideal for offices, homes, and businesses where you want high performance without compromising on style. It should be mounted below 15 feet for optimal results, providing better overall coverage compared to the standard dome.

Panel Antenna

Panel Antenna: The panel antenna broadcasts signal in one direction, making it ideal for covering long, narrow spaces or for penetrating multiple floors. It can be mounted on a wall or ceiling depending on your needs. Panel antennas are versatile and often included in residential and commercial signal booster kits due to their ability to focus the signal in specific areas. In some setups, they can also serve as outside antennas, offering flexibility in both indoor and outdoor installations.

Whip Antenna

Whip Antenna: This small, omnidirectional antenna connects directly to the amplifier and spreads the signal in all directions. It’s less powerful than other types of antennas but compensates with no signal loss between the and the antenna itself. Whip antennas are typically used in entry-level signal booster systems or smaller spaces where simplicity and easy installation are important. 

Mobile Antennas

Mobile antennas are typically designed to be easy to install in a vehicle, like a car or truck, though they are sometimes more permanently installed, like with an RV, semi-truck, or boat. All need to handle a constantly changing outside signal and to be able to efficiently deliver signal to the mobile devices in the vehicle.

Mobile Outside Antenna Options

There are three main types of outside antennas for vehicles: magnet mount, spring or fixed, and marine:

Mini Mag Mount Antenna

Magnet Mount Antenna: This type of antenna is designed to easily attach to the roof of a vehicle using a strong magnet as the base of the antenna, and then have a flexible cable run inside to the amplifier. Magnet mount antennas are typically either 4 inches tall for multi-band systems or 12 inches tall for dual band, and are omnidirectional, so they send and receive in all directions while you're on the move.

Spring Mount Antenna

Spring or Fixed Antenna: This type of antenna is a more permanent mount designed for larger vehicles, such as semi-trucks, RVs, and overland vehicles. There are several versions of this antenna, each suited for different needs:

  • Overland and RV Antenna: This version comes with a versatile mount that can fold down, making it ideal for situations where you may need to lower the antenna for low-clearance areas or while parking. It’s designed for vehicles like RVs, delivery trucks, and off-road overland setups, providing reliable signal reception even in remote areas.
  • OTR (Over the Road) Antenna for Semi-Trucks: The OTR version is built specifically for semi-trucks and large commercial vehicles. It comes with a three-way mount, allowing flexible mounting options on different parts of the vehicle. This version is rugged and designed to handle the tough conditions of long-haul driving.

Both types of antennas are omnidirectional, meaning they can send and receive signals in all directions at the same time, making them perfect for boosting cell signal while the vehicle is moving.

Marine Antenna

Marine Antenna: This type of antenna is designed to be permanently installed on a boat in marine environments, and the included marine mount will attach to any standard marine fixture. The marine antenna is omnidirectional, so it sends and receives in all directions while you're on the water or at the dock, and can withstand the elements during any type of weather. It also has no exposed elements, so it is safe for use on a sailboat.

Mobile Inside Antenna Options

There are three types of inside antennas for vehicles: low profile, cradle, and panel:

Low Profile Antenna

Low Profile Antenna: This type of antenna is designed to be a balance between size and broadcasting power. The low profile antenna is the standard antenna included in most mobile signal booster kits, and is omnidirectional, so it will send and receive signal in all directions from where it is located. The low profile antenna is typically mounted on the dashboard of the vehicle or on the side of a seat to provide boosted signal to the driver and passenger of the car or truck.

Cradle Antenna

Cradle: This type of antenna is typically connected to a mobile amplifier (or the amplifier is built into the back of the cradle) and funnels all boosted signal to the mobile device that sits in the cradle. If you are in a very weak signal area or need to ensure that all of the boosted signal is passed to your mobile device, then a cradle is a good option for you. Please note: with a cradle, the phone or mobile device must sit in the cradle at all times, so you would need to use speaker phone or a headset to make and receive calls.

Panel Antenn for Mobile

Panel Antenna: This type of antenna is meant for larger vehicles that have extra room to fit a building-level antenna. The panel antenna is the same that is found in our building kits and is directional, so the signal comes out of one side of the antenna. It is more powerful than the low profile inside antenna, so should provide more coverage, but its size makes it challenging to use in a smaller vehicle, like a car or truck.

Splitters & Tappers

Splitters and tappers are important components of any signal booster system, as they allow you to split the signal being passed over a cable so you can create a network of inside antennas to distribute boosted signal throughout a location. They can also be used to combine signal coming from multiple antennas into one input for an amplifier.

Splitters

Splitters

A splitter is a component that evenly splits signal from one input to multiple outputs, and vice versa. Splitters typically come in two, three, and four-way versions, so you can split a single signal into up to four evenly split outputs. There is typically a small amount of loss when you use a splitter, so you should take that into account when designing an efficient signal booster system.

Tappers

Tap or Coupler

A tapper, otherwise known as a coupler, is like a splitter, but it splits a signal unevenly, rather than evenly distributing the signal across multiple outputs. It is a critical component and is used when designing signal booster systems for situations where you need to split a signal, but send more signal in one direction and less in another. Tappers come in different ratios of splitting, depending on how much signal you need to send in each direction.

Pole Mounts

Pole Mount

The yagi directional antenna that comes with most building signal boosters is designed to be mounted to a vertical pole or mast on the roof of the building and then aimed at the nearest cell tower. A pole mount is an accessory that includes the vertical pole and mounting hardware to make it easy to install a pole on the roof and mount the external antenna.

Pole antenna mounts vary in length, width, and functionality, with some being a very basic one-foot pole with an L bracket, to more complex units that use angled poles and mounting hardware with multiple installation options to precisely situate the pole in the best possible location. Choose the one that will solve your specific situation the best.

Lightning Protectors

Lightning Surge Protector

After purchasing a high-quality signal booster system, the last thing you want is anything to happen to the amplifier. This is where a lightning protector comes in.

Contrary to its name, a lightning protector (also known as a lightning surge suppressor or arrester) does not protect specifically against a lightning strike, as that would physically destroy the building that the amplifier is in, but rather it prevents the build-up of static electricity in the air caused by storms or other atmospheric conditions that can travel down the antenna cable and electrify the amplifier.

The lightning protector prevents this by connecting directly to the outside antenna cable between the outside antenna and the amplifier. The protector acts as a fuse, so if there is too much current running down the line, the fuse will blow and prevent the surge from reaching the amplifier.

If your building signal booster did not come with a lightning protector, we highly recommend that you purchase one to protect your amplifier. Electrical surges are not covered under any manufacturer's equipment warranty, so it's worth the investment to protect your signal booster.

5. Troubleshooting & Optimizing Your Booster

Every situation is a little different, so you may encounter some challenges while installing and using your cell phone signal booster.

Troubleshooting

While there are many different issues that can arise when boosting cell signal, most fall into one of two buckets: oscillation and overload. We'll cover both of these below and discuss the steps on how to fix each.

If your problem does not fall into either of these buckets, then contact us and our team of signal experts can talk through your situation and recommend ways to remedy it.

Oscillation

Oscillation occurs when the boosted signal that is being broadcast from the inside antenna(s) reaches the outside antenna and causes a feedback loop, similar to a high-pitched sound you hear if you take a microphone too close to an amplified speaker.

Oscillation Diagram

The signal booster amplifier will try to mitigate this issue by reducing the boosting power on the band that is causing the oscillation, which shrinks the coverage area so that it doesn't get back to the outside antenna.

This works a lot of the time, and because it does it automatically, you typically would not notice that it even happened. If you're seeing warning indicators on the amplifier that it is experiencing oscillation, then that means that the amplifier has tried to fix the problem and has reached its limitations, so we need to do other things to fix the problem.

One other thing to note: If the carriers that you need to boost all have roughly the same outside signal strength, then having the amplifier adjust the boosting power to fix oscillation is a good solution. If one carrier is strong and others are weak, then the strong carrier is going to have a much larger coverage area inside of the building, but the amplifier will reduce all boosting by the same amount, and shrink the weak carrier signals to almost nothing while it's trying to fix the strong signal causing the large coverage area. In this case, we'll want to try and fix the problem in another way and let the amplifier work at full power.

Fixing Oscillation

The very first thing to check when dealing with oscillation is whether the directional antenna is pointed across the roof or away from the roof (if you're using an omni antenna, then this does not apply). If the directional antenna is pointed across the roof, then there is a high likelihood that it is picking up boosted signal radiating out, so you should move the antenna to the other side, so that it is facing away from the building.

Once you've confirmed that the outside antenna is facing away from the building, then the main way to fix oscillation is to move the antennas further apart. Typically this means moving the inside antenna further from the outside antenna, but if there is an opportunity to move the outside antenna further away, and potentially higher, while still receiving the same outside signal strength, then that is a good option.

Oscillation Fixed Diagram

When moving antennas, vertical separation is more important than horizontal, though a combination of both is good. We also recommend powering down the amplifier before moving the antennas. Once the antennas are in the new positions, power up the amplifier and see if you're still experiencing oscillation. Keep moving the antennas if so.

If you've moved the antennas as much as possible and are still experiencing oscillation, one last thing to try is to introduce shielding for the outside antenna. If the antenna is outside on the roof, then moving it so that an object, like the chimney or air conditioning unit, is between the antenna on the roof and the rest of the building. If the outside antenna is installed inside, then placing metal, like foil or a metal filing cabinet, behind the antenna to block the boosted signal is an option as well.

Overload

Overload occurs when the outside signal from one or multiple carriers is very strong and is overloading the amplifier with too much cell signal. The amplifier will attempt to compensate for this by reducing the boosting power, but frequently the signal is too strong and the amplifier reaches its limitations before the problem is solved.

Overload Diagram

Fixing Overload

If you're using a yagi directional antenna for the outside, then the best way to mitigate overload is to change the direction of the outside antenna to receive less signal and allow the amplifier to work at full capacity to boost and distribute the signal.

Follow the instructions in the How to Aim a Yagi Directional Antenna guide to incrementally change the direction of the yagi antenna, and then check the amplifier for overload indicators and take signal readings inside with cell phones on each carrier you need to boost.

If it turns out that you're in an urban area and have multiple towers nearby that are overloading your antenna with strong signal from every direction, then the next best option is to use an attenuator, which is a component that sits on the antenna cable and cuts out a set amount of decibels from the signal coming in. An attenuator will cut back the cell signal across all carriers and bands, irrespective of if they are strong or weak, so it's not an ideal solution and should only be used if re-aiming the outside antenna does not help, as it may cause carriers with weak cell signal to have sub-par coverage and performance inside.

Finally, if re-aiming the outside antenna and cutting back the existing cell signal with an attenuator does not provide you with adequate coverage, the last option is to move to a more advanced amplifier that can handle a much stronger outside signal and scale its boosting power significantly down to compensate for the strong existing signal.

Tips to Improve Performance

While most standard signal booster installations should provide you with sufficient coverage for quality voice calls and fast data, if you're looking to tweak your system to provide even more performance, here are some things that you can do:

  • Reduce cable lengths: If the cables that you received with your system are longer than you really need, then purchasing a shorter cable will reduce the amount of signal loss and increase the amount of coverage that your system will be able to provide. Also, be sure that your excess cable is NOT coiled, but rather laid out in a back-and-forth pattern, as coils can cause interference.
  • Upgrade to a lower-loss cable: In addition to shortening cable lengths, you can upgrade your cable to a lower-loss version (more shielded), so your system has more signal to work with and provide more coverage inside.
  • Add more antennas: If you're using one inside antenna, and have a medium to strong outside signal along with a powerful amplifier, then you may have excess boosting capacity that is not being used by the single antenna. Adding another antenna can take advantage of this excess capacity and increase your total inside coverage area. You'll need to add additional cable and a splitter to add the second antenna to the system.
  • Upgrade your antennas: We offer higher-performance antennas that can replace the existing antennas that come with your signal booster system, for more coverage and a better-looking installation.
  • Increase the separation between your antennas: Amplifiers automatically reduce their boosting power if there is any oscillation (feedback) from the inside antenna(s) to the outside antenna. If your amplifier shows any indicator lights or readings that there is oscillation and it's working at reduced capacity, then increase the distance between antennas to allow the amp to work at full boosting power.

6. Frequently Asked Questions (FAQ)

How do I know if I need a cell phone signal booster?

You might need a cell phone signal booster if you regularly experience dropped calls, slow data, or poor signal strength indoors. Common signs include calls cutting out, texts not going through, and needing to be near windows or outside to get service. If this sounds familiar, a signal booster can likely help.

To check whether you need one, it’s helpful to measure your signal strength in decibel milliwatts (dBm) rather than just looking at the bars on your phone. Here’s a more detailed breakdown of signal strength:

  • -50 dBm to -70 dBm: Excellent to strong signal. Calls, texts, and data should work well.
  • -70 dBm to -90 dBm: Moderate to weak signal. You might notice slower data speeds or occasional dropped calls in this range, especially if the signal fluctuates.
  • -90 dBm to -100 dBm: Very weak signal. Calls may be unreliable, and data speeds are slow. This is where a booster can make a big difference.
  • -100 dBm or worse: Extremely weak or no signal. You’re likely to struggle with most cell services indoors.

You can usually check this reading on your phone by entering field test mode through the settings. The closer your number is to -100 dBm or lower, the more likely you’ll benefit from a booster.

Another sign you may need a booster is if the signal outside your building is much stronger than inside. If you step outside and your signal improves significantly, it means the structure of your home or office could be blocking the signal from reaching indoors. In these cases, a signal booster can help by capturing the outdoor signal, amplifying it, and redistributing it inside where you need coverage the most.

Which booster is best for my specific carrier (Verizon, AT&T, T-Mobile, etc.)?

A multi-carrier booster is typically the best choice because it works with all the major carriers—Verizon, AT&T, T-Mobile—and will boost all the frequencies that are authorized by the FCC to be boosted in the United States. This means any carrier using the common five frequencies will be covered, and you won’t have to worry about switching boosters if you change carriers or have visitors using different networks.

If you’re only focused on boosting one carrier, a single-carrier booster could be a better option. These boosters are usually more powerful because they focus on amplifying just one carrier’s signal, but they won’t work for anyone using a different network.

It’s also important to note that certain frequencies, like T-Mobile’s 600 MHz used for 5G, are not authorized to be boosted by any signal booster. But the majority of 5G services, especially those that provide widespread coverage, use frequencies that are supported by multi-carrier boosters. These boosters will work seamlessly with both 4G LTE and the 5G frequencies that have been approved for boosting.

When choosing the right booster, you’ll want to consider more than just your carrier. The type of outside signal you’re receiving is critical. If your outside signal is weak, you’ll need a more powerful booster and a directional antenna to focus on the nearest tower. If your signal is strong or fluctuating, an omni-directional antenna might be better.

The size of the area you need to cover indoors is another big factor. Smaller spaces, like a room or small home, can often be covered by entry-level boosters with a whip antenna. Larger areas, like an entire house or office, usually need stronger amplifiers and multiple inside antennas, such as panel or dome antennas. For businesses, slim or standard dome antennas are common.

If you're boosting signal in a vehicle, the type of inside antenna will depend on your situation. For cars, SUVs, or trucks, a low-profile inside antenna is common, while RVs or boats may use a panel antenna or even a low-profile antenna, depending on the layout.

What size area will the booster cover, and do I need multiple antennas?

The coverage area of a signal booster depends on a few key factors: the strength of your outdoor signal, the power of the booster, and the layout of the space you need to cover. In general, a booster can cover anywhere from 1,500 to over 5,000 square feet, but the actual area will vary based on these factors.

If your outdoor signal is strong, the booster will be able to distribute that signal more efficiently, covering more space inside. However, if your outdoor signal is weak, the booster may only cover a portion of the intended area. For example, if you're in a rural area with poor signal, the coverage might shrink to just a couple of rooms.

  • 1,500 to 2,500 sq ft: Typically for small homes or offices, where a single inside antenna (like a panel or dome antenna) can cover the entire area.
  • 2,500 to 5,000 sq ft: For larger homes or offices, you might need two inside antennas to ensure even coverage across multiple rooms or floors.
  • 5,000+ sq ft: In large spaces like warehouses, office buildings, or multi-story homes, multiple inside antennas are usually required to distribute the signal effectively.

If your space is more complex, with lots of rooms or thick walls, multiple antennas might be needed to ensure consistent signal throughout. You may also need splitters and additional cables to connect those antennas and get full coverage.

If it seems like your situation would require multiple antennas, or if you have questions about selecting the right type or number of antennas, please contact us. We can help guide you through the process and recommend the best solution for your specific needs.

Will a signal booster work with 5G, and is it future-proof?

Yes, most current signal boosters are designed to support 5G in addition to 4G LTE. They boost the low-band and mid-band frequencies that carriers are using for both 4G and 5G services. If your booster is approved by the FCC, it will boost the 5G frequencies that are allowed for consumer signal boosters in the U.S.

It’s important to note that not all 5G frequencies are boosted by consumer boosters. For example, the 600 MHz band used by T-Mobile for 5G is not authorized to be boosted by any signal booster. But most 5G services, especially those providing widespread coverage, use frequencies that are supported by multi-carrier boosters. These boosters work seamlessly with both 4G LTE and the 5G frequencies that have been approved for boosting.

When it comes to being future-proof, many of the same low and mid-band frequencies used for 4G LTE are also being used for 5G, meaning that a signal booster you buy today will continue to support those frequencies as carriers expand their networks. Since most carriers are rolling out 5G on existing frequencies, your booster will likely remain useful for years to come.

What type of antenna should I choose: directional, omni-directional, or high-gain?

The type of antenna you choose plays a big role in how well your booster performs. It depends on how strong and stable your outside signal is, where the nearest cell towers are, and how much coverage you need inside. Here’s a breakdown of the three main types of antennas and when to use each one:

  • Omni-directional antennas pull in signals from all directions. They’re best if you have a moderate to strong signal outside that may be coming from multiple towers or fluctuating in strength. Since they don’t need to be aimed at a specific tower, they’re ideal for areas where signals are coming from different directions or where you might not have a clear line of sight to the tower.
  • Directional antennas focus on a single cell tower and pull in a signal from one direction. They’re best for areas with weak but consistent signals. A common type of directional antenna is the Yagi antenna, which needs to be aimed directly at the nearest cell tower. These are great for rural or remote areas where the signal is coming from one clear direction but may be weak.
  • High-gain antennas (like the LPDA or parabolic grid) are similar to directional antennas but even more powerful. They’re designed for areas with very weak signals and require very precise aiming. These are typically used in extreme cases where the distance to the tower is significant, or the terrain (like hills or trees) blocks most of the signal. High-gain antennas can capture and focus weak signals over long distances, but they require careful installation.

When choosing the right antenna for you, consider the strength and consistency of your outdoor signal. If your signal is strong or coming from multiple directions, an omni-directional antenna is probably your best bet. But if your signal is weak or you’re in a rural area, a directional or high-gain antenna will likely give you better performance.

If you have questions about which antenna would work best for your specific situation, feel free to contact us. We can help guide you through the options to make sure you get the best setup for your needs.

Product Quiz

Not Sure Which Booster is Right for You? Take Our Quiz and Find Out

Answer a few questions and we'll recommend the best solution to solve your cell signal problems.