Wireless interference is unfortunately inevitable, but the trick is to minimize the levels of interference. The three main sources are: Radio, Physical and Electromagnetic interference. Each is explained further below.

Radio Frequency Interference

Wireless routers operate on the 2.4GHz and/or 5.8GHz radio frequencies. There are many home products which also share these frequencies and can cause noise and weaken the router signal. In other cases, strong transmitting/emitting devices can cause interference. Some of these include:

• Cordless baby monitors
• Cordless phones (2.4GHz and 5.8GHz)
• Wireless keyboard and mous
• Microwave ovens
• TV remote controls
• Garage door openers
• 2.4GHz wireless cameras
• 2.4GHz wireless weather stations
• Wireless speakers (2.4GHz and 5.8GHz)
• Satellite TV video transmitters/senders (2.4GHz and 5.8GHz)
• Bluetooth-enabled devices (mouse, keyboard, speakers)
• HAM radio broadcasts
• Certain external electrical sources such as power lines, electrical railroad tracks, and power stations
• Neighbors' wireless devices
• Wifi boosters and range-extenders (must be on a different wifi channel than the router)
• Certain external monitors and LCD displays: Certain displays may emit harmonic interference, especially in the 2.4GHz band between channels 11 and 14. This interference may be at its worst if you have a portable computer with the lid closed and an external monitor connected to it. Try changing your access point to use 5GHz or a lower 2.4GHz channel

 Physical Interference

The density of the materials used in a building's construction determines the number of walls the RF signal can pass through and still maintain adequate coverage. Concrete and steel walls are particularly difficult for a signal to pass through. Furniture, filled cinder block, brick, rock fireplace walls, adobe or stucco construction will weaken or, at times, completely prevent wireless signals. Fish tanks, water heaters, any appliances that contain metal, filing cabinets, foil-backed insulation, metal bookcases, tinted windows that use metal-based films and aluminum window screens can also weaken signals.

 Electromagnetic Interference

Electrical interference comes from devices such as computers, fridges, fans, lighting fixtures, or any other motorized devices. The impact that electrical interference has on the signal depends on the proximity of the electrical device to the wireless router. Advances in wireless technologies and in electrical devices have reduced the impact these types of devices have on wireless transmissions. Some of these include:

• Electric power transmission lines
• Electric motors
• Doorbell transformers
• Toaster ovens
• Electric blankets
• Ultrasonic pest control devices
• Electric bug zappers
• Heating pads
• Touch controlled lamps
• Solar Storms