About 5 to 10 kilometers, 500mW (1/2 Watt or 27dBm): Outdoor, long distance focused routers. For the 2.4GHz band, there are 14 channels total. What does that mean, though? An un-modulated FM wave might look like: And a modulated FM radio wave has higher and lower frequencies indicating higher and lower audio frequencies in the signal: From left to right, we have the normal, un-modulated wave, then the lower frequency wave (representing lower audio amplitudes), then the higher frequency wave (representing higher audio amplitudes). If the signal vibrates very slowly, it has a low frequency. Will your passport be valid for travel to the EU after Brexit? To simplify, there are two ways for an internet signal to reach your device at 35,000 feet. But in this article, I'll break it down for you. Below we can see the span of frequencies that are commonly used in communications. If you try and listen to an AM signal with a radio in FM mode, it won’t work. But how does in-flight Wi-Fi actually work? Planes connect to satellites in geostationary orbit (35,786km above the planet), which send and receive signals to earth via receivers and transmitters. A router’s transmit power can be measured with two scales -- milliwatts (mW) or dBm: A few examples of the transmit power levels in common Wi-Fi hardware is below: 10mW (10dBm): Laptop or smartphone, or very low cost Wi-Fi router. The router then converts the frequencies back into binary code and translates the code into the Internet traffic that you requested, and the router receives that data through a hardwired Internet cable. Gogo, meanwhile, currently has a monopoly on US in-flight Wi-Fi, with a network that covers the whole country. One gigahertz, on the other hand, is one billion waves per second. There are many types of modulation, and different technologies can use one or more types to send and receive information. It has been criticised for its painfully-slow upload and download speeds, but its new 2Ku service promises upgraded antennas and satellite services, delivering up to 70 Mbps – much faster than your average connection on land. When you click on this article, your request is translated into a bunch of 1s and 0s. The type of modulation is what makes them different. In this article, we'll look at the technology that allows information to travel over the air. If there are areas that are then left out, how will those areas be included in the network? The best place to check what is allowed in your area is online. Below, we can see the same routers, but with more distance between them. The optimal signal range for outdoor wireless equipment is between -40dBm and -60dBm. In the United States, only channels available for building mesh networks are 36, 40, 44, 48, 149, 153, 157, 161, and 165. This means most devices can only understand a very specific kind of wireless signal. Everything computers do is based in binary code, a series of 1s and 0s. As a receiver moves away from a wireless router, the signal it hears will get “quieter” -- in other words, the power it receives will go down. Wi-Fi signal is distributed to plane passengers via an on board router. According to UK communications regulator Ofcom, the average UK household internet speed reached 28.9 Mbps in 2016 – so in-flight Wi-Fi has a long way to go to catch up. Cellular phones use many different frequencies. In this case, the routers have a weaker connection because the signal is near the limit of what the routers can hear. Television: Many frequencies from 470MHz to 800MHz, and others. It won’t hear signals behind it or to the sides as well or at all. The first type of antenna is also the most common--omnidirectional. The all-direction strength of these antennas comes with the drawback of transmitting a weaker signal. If the signal vibrates very quickly, it has a high frequency. Since the signal is all going one way, the power that would be sent out in all directions with omnidirectional nodes is now focused, increasing the power in that direction.