A little about radio communication

• What happens when you are listening to the radio in your car, and you drive out of the city? The signal gets weaker. The further apart two radios are, the weaker the signal between them. The same goes for WiFi.
• Why can you hear some radio stations from further away than others? The more powerful the transmitter, the further away the signal can be detected. The same goes for WiFi.
• Why can some radios detect weak signals better than others? The better the design of a radio, the more sensitive it is to a weak signal. The same goes for WiFi.
• What if you have two identical radios -- might one still detect a weaker signal than another? Yes, if it has a more focused antenna. The same goes for WiFi.
• Why do you sometimes have to step outside of a building to get a good cell phone signal? The walls of the building absorb power. The same goes for WiFi.
• Even if you are outside, you might get a weak cell phone connection, why? You may be far from a base station? The same goes for WiFi.
• What changes when you switch your radio or television set from one station to another? You are changing the frequency of the signal it is detecting. The same goes for WiFi.
• Can two radio or TV stations transmit at the same frequency in a given location? No, they would interfere with each other.
• What keeps two radio stations from transmitting at the same frequency in a given location? They must license the frequency from the Federal Communication Commission and are limited in the amount of power they may use.
• Does a WiFi radio require an FCC license? No -- that enables them to be very cheap, mass market items.
• Why don't WiFi radios interfere with each other? They use very low power.
• But, what if WiFi radios are close to each other, wouldn't they interfere then? Yes, so you would set them to use different channels.
• What do WiFi radios do if the link between them becomes weak and errors are detected? They slow down, reducing the transmission rate in an attempt to improve accuracy.