The No-Nonsense Guide To Mobile Signal Boosters

The No-Nonsense Guide To Mobile Signal Boosters

30 September 2025
Isobel Baker

If you’ve ever struggled with dropped calls, slow data, or those frustrating 'dead zones' in your office or building, you might've wondered whether a mobile signal booster could help. At Signal Solutions, we get asked a lot of questions about how boosters work, whether they’re legal, and what kind of difference they actually make.

So, in this post, we’re answering some of the most common queries we hear from customers. This will hopefully give you a clear picture of what mobile signal boosters can (and can’t) do.

1. Are mobile signal boosters legal in the UK?

Yes but... Only if they meet Ofcom regulations. The good news is that all the equipment we install, including Nextivity CEL-FI boosters, is fully compliant for use in the UK and across Europe.

Illegal boosters (often bought online from unverified sellers) can interfere with mobile networks and even cause disruption for other users. That’s why it’s so important to choose a professional installation with certified equipment.

2. How do mobile signal boosters actually work?

It’s simpler than you might think. A booster system is made up of a few key components that work together:

External antennas - Mounted outside (usually on the roof), external antennas capture the mobile signal from the nearest network mast and brings it inside.

Network unit - This is the 'brains' of the system. It cleans up the signal, removes noise and interference, and boosts its strength.

Coverage units - These take the improved signal from the network unit and distribute it across different areas of the building.

Internal antennas - Finally, internal antennas rebroadcast the boosted signal into the spaces where people actually need it, so your devices can connect seamlessly.

In larger buildings, we may also use fibre hubs to make sure the signal reaches every corner without dropping off.

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3. Will a booster work if I have no signal at all?

No, a booster can’t create a signal from nothing. It needs at least a weak mobile signal outside to work with.

The good news is that in most cases, even a very faint signal can be captured and amplified to provide strong, reliable coverage indoors.

4. Do boosters work with all mobile networks?

Yes. Nextivity CEL-FI boosters are designed to work across all major UK and European networks. That means whether you’re on EE, O2, Vodafone, Three, or another provider, you’ll benefit from improved coverage.

This is especially useful in workplaces where staff and visitors may all be on different networks.

5. What’s the difference between a booster and Wi-Fi calling?

Wi-Fi calling can be handy, but it relies on your broadband connection. If your internet is slow or goes down, so does your ability to make calls.

A mobile signal booster strengthens the actual mobile network signal. That means you’re not relying on Wi-Fi, and you’ll have consistent coverage throughout your building.

For more of an in-depth comparison, you might be interested in this blog post: Comparing Signal Boosters vs. Other Connectivity Solutions

6. What types of buildings can benefit from a signal booster?

Pretty much any type of building where mobile coverage is poor. We’ve installed boosters in:

  • Offices and co-working spaces

  • Hotels and leisure venues

  • Warehouses, stores and industrial sites

  • Schools and healthcare facilities

Whether it’s thick walls, energy-efficient glass, or just being in a tricky location, boosters can overcome the barriers that block mobile signals.

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7. How many rooms or floors can one booster cover?

That depends on the size and layout of the building, as well as the materials used in construction.

For smaller properties, a single system may be enough. For larger or more complex sites, we use multiple coverage units and internal antennas to ensure every corner gets reliable signal. We may even include a fibre hub.

8. Will a booster improve both calls and mobile data?

Yes. A properly installed booster improves both voice quality and data speeds. That means clearer calls, fewer dropouts, and faster browsing, streaming, and downloads.

9. Is installation disruptive or complicated?

Not at all. Our team handles everything from site surveys to installation and testing. The key is placing the external antenna in the best possible location to capture the strongest signal, then designing the system so coverage is evenly distributed indoors.

Most installations are completed with minimal disruption, and once it’s in place, the system runs quietly in the background.

10. Do boosters need ongoing maintenance?

Mobile signal boosters are designed to be highly reliable, so they don’t require constant servicing. Once installed, the system will continue to deliver strong coverage day in, day out.

That said, we know this is a significant investment, which is why we offer ongoing support and can carry out periodic checks if needed - especially in larger or more complex buildings. This ensures your system continues to perform at its best and gives you peace of mind that your investment is protected for the long term.

11. Do you offer a guarantee on your installations?

Yes. All of our installations come with a 5-year guarantee, which is longer than the standard offered elsewhere in the industry. We provide this because we have complete confidence in both the CEL-FI equipment we use and the quality of our installation work.

For our customers, it means peace of mind, knowing that your investment is protected and that we’ll be here to support you long after the installation is complete.

12. What happens if my booster stops working?

It’s rare, but if something does go wrong, you’re covered. Our team can usually diagnose issues quickly, and if replacement parts are needed, we’ll handle that under the guarantee where applicable.

13. Can you monitor the system online or digitally?

Yes, with our Amplifi-Qx system. This is our flagship solution, combining CEL-FI technology with our own proprietary monitoring and management software.

Unlike standard signal boosters, Amplifi-Qx provides intelligent, self-optimising coverage with real-time monitoring through our exclusive Amplifi-Qx web app and mobile app.

Available in both Digital (QUATRA) and Analogue (GO) configurations, Amplifi-Qx delivers superior performance while giving you the confidence of knowing your signal enhancement solution is always working at its best.

14. How long does installation typically take?

For smaller properties, it’s often just a couple of days. Larger commercial sites with multiple coverage units or fibre links may take a little longer, but we always plan the work carefully to minimise disruption.

Our team handles everything from the initial site survey to the final testing, so once we’re finished, you’ll have reliable coverage straight away.

How long does an installation typically take? - Youtube Video

15. Can the system be expanded in the future if my needs change?

Yes. One of the advantages of CEL-FI and our Amplifi-Qx solution is that they’re fully scalable. If your business grows, you move into a larger building, or you need to extend coverage into new areas, the system can be expanded with additional coverage units, fibre links, or antennas.

This flexibility means your investment is protected. You won’t need to start from scratch if your requirements change. Instead, we can adapt and build on your existing system to keep you connected wherever you need it.

Mobile signal boosters are a simple, effective, and legal way to solve poor mobile coverage. Whether you experience dropped calls, or you need reliable connectivity across a large commercial site, a properly installed booster can make all the difference.

If you’ve got more questions, or you’d like to find out how a booster could work in your building, fill in our free solution design and quote today.