Why Does My Wi-Fi Keep Dropping Out Even Though the Signal Is Strong?
We’ve said it before, and we’ll say it again for the people in the back – A strong Wi-Fi signal does not necessarily mean a reliable Wi-Fi connection.
You can have full bars of Wi-Fi signal but still be experiencing:
- Dropped Teams/ Zoom calls
- Slow or intermittent internet
- Applications disconnecting
- Devices repeatedly reconnecting
- Poor voice quality
- High latency
- Bluetooth problems occurring at the same time
The reliability of Wi-Fi depends on a lot more than just the strength of the signal. We unfortunately see many clients where they’ve tried to fix the problem by adding another Access Point – But this rarely works. Intermittent Wi-Fi problems require measurement and diagnosis to identify exactly what the problems are and how best to fix them. Throwing in another Access Point can cause more issues than they fix if not done correctly.
Here at Geekabit, we specialise in investigating the RF environment of your wider network, rather than just assuming that every reported Wi-Fi problem is caused by weak coverage. News Flash: It’s often not.
Does this sound like one of your employees?
An employee comes to the IT Manager and complains that their Wi-Fi keeps dropping out, despite their laptop showing 3 or 4 bars of signal.
Surely then, the Wi-Fi can’t be the problem? Wrong! We can see the logic, but hopefully your IT Manager gets a little more curious than either wrongly assuming that the Wi-Fi can’t be the problem, or just installing another Access Point in the vicinity of the employee experiencing problems.
But signal strength is only one measurement of wireless performance.
A reliable Wi-Fi connection depends on:
- Interference
- Noise
- Channel utilisation
- Access Point placement
- Network design
- Client behaviour
- The infrastructure behind the Wi-Fi
What do the Wi-Fi bars actually tell you?
The strength of a wireless signal when a device receives it is measured in Received Signal Strength Indicator, or RSSI.
The signal bars you see on your device show how strongly it can ‘hear’ the Access Point.
What these signal bars don’t tell you, is:
- How busy the channel is
- Whether another transmitter is interfering
- Whether packets are repeatedly being retransmitted
- Whether the access point is overloaded
- Whether the device has chosen the best AP
- Whether DHCP or DNS is working properly
- Whether the internet connection itself is stable.
Think of it as being a bit like someone talking loudly in a crowded room – You might be able to hear their voice, but struggle to understand what they are actually saying.
What people sometimes forget or don’t realise, is that Wi-Fi is two-way communication. Hearing the AP doesn’t automatically mean that the
- Also mention that Wi-Fi is two-way communication. A device hearing the AP strongly doesn’t automatically mean the AP can hear the client device equally well.
Interference can cause problems despite excellent signal
RF or Radio Frequency is what powers wireless technologies like Wi-Fi, Bluetooth, mobile phones, radio/ TV broadcasting, and radar.
Wi-Fi operates in this shared radio spectrum, meaning that interference can occur – Both through the competition for airtime and physical blocks to the waves.
This means that the frequencies used by Wi-Fi can be interfered with by other Wi-Fi devices as well as non-Wi-Fi devices. Things that can cause interference are:
- Bluetooth devices (although it’s important to point out that not every Bluetooth device destroys Wi-Fi – Modern systems are designed to co-exist. But in congested or unusual RF environments, interference can be relevant)
- Wireless audio/ video equipment
- Some IoT equipment
- Microwaves
- Cordless/ wireless equipment
- Specialist industrial or building equipment
- The buildings themselves
Remember that interference can be intermittent – An employee might complain to the IT Manager at 10am that there’s a problem, but by the time they have a chance to investigate it at 2pm, it’s apparently disappeared.
Wi-Fi Scanner vs Spectrum Analyser
It’s important to note the distinction between these 2 Wi-Fi tools.
A conventional Wi-Fi Scanner can see Wi-Fi networks and Access Points. It cannot necessarily tell you what non-Wi-Fi radio activity is occupying the spectrum.
Spectrum Analysis examines RF energy itself. This can reveal interference that wouldn’t appear as another SSID.
Professional troubleshooting of Wi-Fi problems would likely therefore combine Wi-Fi Analysis with Spectrum Analysis.
Your device may be connected to the wrong access point
Did you know that a device doesn’t necessarily connect to the AP that’s physically nearest? You do now.
Your device ultimately makes many roaming decisions by itself. A laptop can remain attached to an AP further away, when there is a better one available.
It’s also worth noting that the way a building is constructed can make physical distance misleading. For example, an AP that appears close by on a floor plan, might actually be:
- Upstairs
- Through a reinforced floor
- Behind several walls
- Around a corridor
- Serving users from an unintended location
Remember that a strong enough signal for connectivity, doesn’t necessarily mean it’s sufficient for a consistently good user experience.
Proper AP placement really matters.
Too many access points can also cause problems
If you’re experiencing Wi-Fi problems, adding more AP’s isn’t necessarily the solution. You can read more about that here.
The problem may actually be with the network design. Poorly designed networks can have:
- Excessive transmit power
- Overlapping coverage
- Too many AP’s sharing channels
- Poor channel allocation
Badly configured APs can actually increase contention.
Wi-Fi networks should be designed around coverage and capacity, rather than simply filling a building with radios. .
Channel width matters — particularly on 2.4 GHz
A Wi-Fi channel width of 20 MHz provides a narrower, more stable connection with less interference, while 40 MHz bonds two channels together to double your theoretical speed, but at the cost of higher susceptibility to interference.
The 2.4 GHz band has very limited usable spectrum. Using unnecessarily wide channels consumes more of it.
In busy environments, 40 MHz channels on 2.4 GHz can contribute to poor coexistence and increased contention.
For many business deployments, 20 MHz channels on 2.4 GHz are the sensible choice.
Wider isn’t automatically faster in a real-world environment.
It’s important when channel planning that your IT Manager considers neighbouring networks and the actual RF environment.
The problem might not actually be Wi-Fi
Picture this. One of your employees rings the IT Manager and says “The Wi-Fi went down!”
This user can be experiencing a failure anywhere along this chain:
Laptop → Wi-Fi → AP → switch → router/firewall → ISP → internet service
The potential cause of this failure could be:
- Failing or incorrectly configured network switches
- Ethernet links negotiating at the wrong speed
- Damaged cabling
- PoE problems
- VLAN/configuration errors
- DHCP exhaustion or slow DHCP responses
- DNS failures
- Gateway/router problems
- ISP instability
- Packet loss upstream
- Internet connection congestion
Unfortunately, just replacing APs isn’t going to fix any of these problems.
Why intermittent Wi-Fi problems are difficult to diagnose
Perhaps the only good thing about persistent Wi-Fi faults is that they are relatively easy to diagnose because they’re still present when the Wireless Engineer arrives.
Intermittent faults on the other hand, require evidence.
A short visit from a Wi-Fi Engineer might find a network that appears to be completely healthy. This is why it’s important to engage a wi-Fi specialist who can conduct a useful investigation that includes:
- Spectrum analysis
- Wi-Fi scanning
- Channel utilisation measurements
- AP/controller logs
- Roaming information
- Latency and packet-loss testing
- Wired-network testing
- Longer-term monitoring
Where appropriate, leaving a monitoring device onsite can help establish exactly when failures occur and whether the LAN, DNS, gateway or internet connection is affected simultaneously.
The aim of our expert Wi-Fi Engineers is to correlate your user’s reported experience with measurable network behaviour. Then we can get to work in providing the fix.
Why Bluetooth dropping out at the same time can be an important clue
Bluetooth also operates in the 2.4 GHz spectrum.
If users report both Wi-Fi and Bluetooth problems in a particular location, that is very useful diagnostic information.
Whilst it doesn’t automatically prove RF interference, it does give an engineer a reason to investigate the local 2.4 GHz spectrum rather than concentrating solely on the Wi-Fi configuration.
This is an excellent example of why asking users exactly what they experience can be as important as looking at the controller dashboard.
How should a business investigate Wi-Fi that keeps disconnecting?
If your business is experiencing intermittent Wi-Fi problems, then it’s time for your IT Manager to get curious and start recording some data. Does the problem affect one user, one room, one AP or the whole building? Start making a log of:
- Where the problem happens
- When it happens
- Which devices are affected
- Whether wired devices are affected
- Whether Bluetooth is affected
- Whether users still show strong Wi-Fi signal;
- Whether it happens during particularly busy periods.
Don’t be tempted to try random things before getting curious. The following actions can mask the underlying fault or even make the RF environment worse.
Things to avoid doing:
- Rebooting everything repeatedly
- Installing additional APs
- Turning every AP’s transmit power to maximum
- Widening channels in pursuit of higher headline speeds
What does a professional Wi-Fi investigation involve?
We sometimes see clients assuming they know what the Wi-Fi problem is and trying what they think is the obvious solution. But you need to start with the reported symptoms and get curious about what the cause could be.
A professional Wi-Fi investigation starts with the reported symptoms and uses them to lead an examination of the existing Wi-Fi design and configuration.
A specialist Wi-Fi Engineer will measure the RF environment and look for both Wi-Fi and non Wi-Fi interference. They will assess channel utilisation and channel planning.
Access Point placement will be checked, alongside actual client associations.
The wired infrastructure will also be examined as well as the internet path where relevant.
All of the data from these investigations leads to the Geekabit team making evidence-based recommendations. This could be new hardware, or some configuration changes to your existing network. Sometimes it’s as simple as repositioning equipment or fixing something elsewhere in the network.
Our expert Wi-Fi Engineers here at Geekabit will always find the cause of your Wi-Fi problems before recommending the cure. You can contact our friendly team to find out more.
Remember: Strong Wi-Fi signal doesn’t guarantee good Wi-Fi
Reliable wireless networks depend on clean spectrum, sensible RF design, appropriate AP placement, sufficient capacity and a healthy network behind the Access Points.
If your business is experiencing repeated Wi-Fi dropouts, the most useful first step isn’t necessarily buying more equipment. It’s getting curious and establishing what is actually failing.
If you need any help with business Wi-Fi troubleshooting or you are interested in a Network Health Check for your business, please don’t hesitate to get in touch with our team here at Geekabit. Our professional Wi-Fi Engineers are experts in their field and ready to help make your Wi-Fi network more reliable so your business operations run smoothly.
FAQs
Why does my Wi-Fi keep disconnecting when I have full signal?
Full Wi-Fi signal generally means your device can receive a strong signal from the access point. It doesn’t tell you whether the radio channel is congested, whether interference is present, whether packets are being lost or whether another part of the network is failing. A device can therefore display full Wi-Fi bars while still experiencing an unreliable connection.
Can Wi-Fi interference cause devices to disconnect?
Yes. Wi-Fi and other radio transmissions can interfere or compete for airtime, particularly in busy environments. This can result in reduced throughput, increased latency and retransmissions and, in more severe cases, unreliable connections. Spectrum analysis can help identify RF activity that a normal Wi-Fi scanner may not detect.
Can Bluetooth interfere with Wi-Fi?
Bluetooth and 2.4 GHz Wi-Fi share the same general frequency band and are designed with coexistence mechanisms. Usually they operate alongside each other successfully. However, heavy or unusual 2.4 GHz RF activity can affect wireless performance. If Bluetooth and Wi-Fi devices experience problems simultaneously in the same location, it can be a useful reason to investigate the local RF environment.
Why does my Wi-Fi only drop out in one room?
A location-specific problem can be caused by AP placement, building materials, interference, channel conditions or the device connecting to an AP that isn’t ideally positioned to serve that room. Measuring the network from the affected location is often more useful than relying solely on an AP controller or floor plan.
Will adding another Wi-Fi access point stop dropouts?
Not necessarily. Another AP can improve coverage where signal is genuinely inadequate, but it won’t solve problems caused by interference, DHCP, DNS, cabling, switching, broadband or poor configuration. Adding APs without considering channel planning can sometimes make wireless performance worse.
Should businesses use 20 MHz or 40 MHz channels on 2.4 GHz?
In many business environments, 20 MHz channels are preferable on 2.4 GHz because the band has limited spectrum available. Using 40 MHz channels consumes considerably more of that spectrum and can make effective channel planning and coexistence with nearby networks more difficult.
What’s the difference between Wi-Fi analysis and spectrum analysis?
Wi-Fi analysis examines Wi-Fi networks, access points, channels and related protocol information. Spectrum analysis looks at radio-frequency energy across the band, which can expose interference that isn’t generated by Wi-Fi equipment. Professional troubleshooting may use both because a Wi-Fi scanner alone cannot identify every source of RF activity.
How can I tell whether the problem is Wi-Fi or my internet connection?
Testing connectivity at several points can help isolate the problem. An engineer might test communication to the local gateway alongside DNS, external internet connectivity, packet loss and latency. Comparing wired and wireless devices can also help establish whether the fault is within the Wi-Fi network or further upstream.
Why does office Wi-Fi work perfectly sometimes and badly at other times?
Changing numbers of users, channel utilisation, neighbouring networks, intermittent RF interference and internet utilisation can all cause performance to vary throughout the day. Longer-term monitoring and spectrum analysis can be particularly useful when the fault isn’t present during an engineer’s visit.
What information should I record before reporting an intermittent Wi-Fi problem?
Record when and where the problem occurs, which devices are affected, whether the device still shows Wi-Fi signal, what application was being used and whether wired or Bluetooth devices experience problems at the same time. Patterns in this information can substantially narrow down the potential causes.
