How to troubleshoot Wi-Fi Interference with NetSpot

Wi-Fi is a very advanced technology, a magic of its kind. Although it is not magic of course but a logically explainable effect of radio waves. When your devices use WiFi to connect to Internet the signals are sent with radio waves and despite of all advanced features wireless interference can happen. As a result your wireless connection may become weak and unreliable.

Wireless interference explained


Your wireless network is most probably affected by wireless interference when the following symptoms occur: an intermittent connectivity or unexpected disconnections, delays in connection and data transfer, slow network speeds, and poor signal strength.

The usual source for Wi-Fi interference is something that causes radio frequency interference. The reasons can be different:

  • The way wireless router is positioned
  • Physical obstacles, like walls and floors
  • Any other wireless appliances (baby monitors, garage door openers, etc.)
  • Kitchen appliances, such as microwave or fridge
  • Other Wi-Fi networks in the same space

Positioning of a Wireless Router


Obviously the way you position your wireless router will have effect on your coverage area and WiFi signal strength.

How to troubleshoot

  • Put the router in the middle of the space where network is. If the router is placed off the middle, then the signal won't be even
  • Make sure the router antenna is vertical. Many antennas are adjustable and can be horizontal, but the straight up is usually the best position
  • Put your router on an elevated surface. The reception will be better on the desk rather than on the floor

Physical obstacles


The building of the space (be it a home or an office) affects wireless communication range and speed. The materials used in the construction also matter, e.g. wood or glass will have the minimal impact, while concrete, brick and metal can make the connection more difficult to establish and cause slow network speeds. So don't forget to pay attention to the type of materials the router is placed by.

Have a look at the list of physical obstacles and what effect they may have on the wireless signal.

Type of Barrier Interference Level
Wood Low
Plaster Low
Synthetic Material Low
Glass Low
Water Medium
Bricks Medium
Marble Medium
Concrete High
Metal High
Mirror Very High

How to troubleshoot

  • Try moving the wireless device to a different spot. Even a couple of feet can make a huge difference in WiFi signal strength. Some wireless devices, like Wi-Fi routers or cordless phones have adjustable antennas. Try and point that antenna in a different direction to see if it can reduce WiFi interference as well.
  • Add a Wi-Fi extender to your network. These devices re-transmit the signal from your router even if it is on a different room thus providing better connection to a device that was receiving a very poor signal or was cut off at all.
  • There are also Powerline adapters to consider. These are very good for larger spaces with thicker walls and floors. These adapters use your existing electrical Ethernet wires sparing you the need of buying new expensive wiring. Connecting a powerline adapter to a Wi-Fi extender is an efficient method of extending WiFi connection to the most remote spots in your space.

Frequency Interference (Other wireless appliances)


Even if the devices are not Wi-Fi related they may be working on the same 2.4GHz or 5GHz frequencies. Bluetooth devices, cordless phones, baby monitors are the examples. Also such appliance as microwave may be generating the radio frequency noise and as a result the network may be slower or disconnect. Have a look at the list below with the possible sources of signal interference.

  • Microwave — the closer the router is to microwave the more network interference you can expect to occur when the microwave is in action. That is especially true for older wireless routers that just like microwaves operate in the 2.4 GHz spectrum.
  • Cordless Phone — again 2.4 GHz spectrum. Just like previous item these phones can cause large signal interference. Wi-Fi Interference will occur during active call time.
  • Poorly Wired Satellite Dish — if a satellite dish is not properly wired or the old wires are deteriorating it can cause quite a signal interference.
  • Other Wireless Devices — any wireless device can technically be the reason for a signal interference. These can be wireless speakers, baby monitors, garage door openers, etc. Some other wireless devices operating in 2.4 GHz or 5 GHz spectrum, including microwave transmitters, wireless cameras can also contribute to wireless interference.
  • Power sources — electrical railroad tracks or power lines that are in close proximity can be causing WiFi interference. If you can try not to position your Wi-Fi router near power lines in the wall or close to the breaker box.
  • Poorly shielded cables — if you suspect that a certain device is the cause of interference, try to disconnect it and use a different cable for it.
  • Some external monitors and LCD displays — these can be specifically annoying on the 2.4GHz band between channels 11 and 14. If you are working with a monitor connected to a closed laptop the interference might be even stronger. Make your access point use 5 GHz or a lower 2.4 GHz channel.
  • Neighbors' WiFi — powerful WiFi networks that overlap can affect each other.

How to troubleshoot

It is always a good idea to turn off and unplug electronic devices temporarily to see how it affects the wireless interference issue. Another option is moving the wireless devices. If you feel like there is a specific wireless device causing the issue, check if it offers options to switch WiFi channels. Try switching to the robust 5GHz frequency. If it still doesn't really help you can try the updated models with better radio wave noise shielding.

Frequency interference can also be fixed by changing the channel for the WiFi router. The channel can be usually set from 1-11 for the broadcast frequency. The more expensive and advanced routers can broadcast at 5 Ghz frequency, which is great.

Interference from competing Wi-Fi networks


If the Wi-Fi networks around are using the same frequency channel they might be causing the interference as well. A regular WiFi network in North America can work on either of 11 channels, while other countries have 13. So if more than one network is using the same channel, there will always be a competition for the bandwidth. Cities and large apartment buildings are especially prone to interference issues because more WiFi networks are overlapping and probably using same channels.

How to troubleshoot

Often the latest WiFi routers offer an option to find the least busy Wi-Fi channel. Look into the user manual to see how to enable that option and set it up properly. If you have automatic switching enabled but still get the slow speed and a breaking connection try to set up the channel manually and do a speed test to see which one is the fastest. Use NetSpot as a Wi-Fi Channel Scanner.

Other Obstacles


Other issues that can influence the WiFi performance may not fall into any of traditional categories but still need to be considered:

  • Hearing aid can cause some signal disruption when very close.
  • Power lines, power stations, railway tracks may not be the cause of interference but if you have a feeling they may be affecting your network, try playing with that too.
  • Blasting area. For example a mine.
  • Your hand. Yes, the way you hold your phone may interfere with network signal as well. Change your grip and see if you can get a better WiFi signal.

How to beat Wi-Fi Interference with NetSpot


Whenever you are experiencing some issues with the wireless signal NetSpot will help you determine whether wireless interference is taking place. NetSpot can show you what wireless channels the networks around are using and can give you recommendation what channel is the best option for your network. With NetSpot you can walk the perimeter and determine the weakest spots in your WiFi and the strongest.

The WiFi performance will always stand down to that one of a wired network, however it keeps getting better each year and the gap becomes less and less between the two.

A dual band 802.11ac router can give you the best WiFi performance especially when positioned correctly. Set up multiple routers in bridge mode on different levels of a building to boost WiFi signal even more.


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