5G Frequency Bands

- Licensed and Unlicensed Spectrum

All wireless technologies use the airwaves to transmit and receive information. In order for many different technologies to use the airwaves simultaneously, wireless spectrum is carved up into chunks called frequency bands. Licensing these frequencies is a way of ensuring Mobile Network Operators (MNOs) do not interfere with each other's transmissions.

Without licensing, interference would cause problems on the transmissions on both sides. It's a good way to ensure that every provider knows where the others' signal is and to ensure that users get the best quality because there is a dedicated frequency for their use. The downside of the unlicensed frequencies or bands is that anyone else can use the same frequency ranges, which can cause interference, so when using an unlicensed technology like WiFi, users may have to make adjustments to avoid this interference. Regulations exist around these bands, so using unlicensed radio bands is not a free-for-all. The big difference between licensed and unlicensed bands is that the licensed bands are allowed to be used only by the company that licensed them, whereas the unlicensed bands are used by anyone who wants to use them.

Spectrum is a powerful resource that we can leverage as the industry develops. It is more important than ever. The world has gone mobile, and as the demand for wireless services increases, our dependence on spectrum will only grow greater. As things stand, the licensing model limits our ability to grow our use of wireless broadband, so the differences between licensed and unlicensed spectrum, and the way this is approached, will become increasingly important.

- Radio Wave Frequencies

Radio wave frequencies range anywhere from 3 kilohertz (kHz) up to 300 gigahertz (GHz). Every portion of the spectrum has a range of frequencies, called a band, that go by a specific name. Some examples of radio spectrum bands include extremely low frequency (ELF), ultra low frequency (ULF), low frequency (LF), medium frequency (MF), ultra high frequency (UHF), and extremely high frequency (EHF). 

Spectrum use and availability are the most important factors in fielding a viable 5G network, as they will determine the speed, volume, and latency of data transfer going forward. 4G data transfer capabilities cannot keep pace with current demand, and the 5G step-change would address the increasing rate of data consumption by fielding a functioning 5G network using mmWave bands, sub-6 bands, or both.

5G carries information wirelessly through the electromagnetic spectrum, specifically the radio spectrum. Within the radio spectrum are varying levels of frequency bands, some of which are used for 5G data. 5G frequency bands is that different companies use different parts of the spectrum to transmit 5G data. Using one part of the spectrum over another impacts both the speed of the connection and the distance it can cover. 

- Frequency Determines 5G Speed & Power

All radio waves travel at the speed of light, but not all waves react with the environment in the same way or behave the same as other waves. It's the wavelength of a particular frequency used by a 5G tower that directly impacts the speed and distance of its transmissions: Higher Frequency (Faster speeds, Shorter distances), Lower Frequency (Slower speeds, Longer distances). 

Wavelength is inversely proportional to frequency (i.e., high frequencies have shorter wavelengths). For example, 30 Hz (low frequency) has a wavelength of 10,000 km (over 6,000 miles) while 300 GHz (high frequency) is just 1 mm.

When a wavelength is really short (such as the frequencies at the higher end of the spectrum), the wave form is so tiny that it can become easily distorted. This is why really high frequencies can't travel as far as lower ones. 

Speed is another factor. Bandwidth is measured by the difference between the highest and lowest frequency of the signal. When you move up on the radio spectrum to reach higher bands, the range of frequencies is higher, and therefore throughput increases (i.e., you get faster download speeds).