Unlicensed vs Licensed
The difference between unlicensed and licensed wireless spectrum refers to the way that different frequencies of the radio spectrum are used for wireless communication.
Unlicensed spectrum refers to frequencies that are available for use by anyone without the need for a license. These frequencies are typically used for lower-power applications such as WiFi, Bluetooth and other short-range wireless devices. Unlicensed spectrum is less regulated and typically less expensive to use.
Licensed spectrum, on the other hand, refers to frequencies that are allocated and controlled by government regulatory bodies for specific uses. These frequencies are typically used for higher-power applications such as cellular networks, satellite communication and other long-range wireless devices. Licensed spectrum is more regulated and typically more expensive to use. It is also more reliable and secure.
Low, Mid and High Bands
Low-band wireless spectrum refers to frequencies below 1 GHz, such as the 600 MHz and 700 MHz bands. These frequencies have the advantage of being able to penetrate buildings and travel long distances, making them well-suited for providing coverage in rural and suburban areas.
Mid-band wireless spectrum refers to frequencies between 1 GHz and 6 GHz, such as the 2.4 GHz and 5 GHz bands. These frequencies offer a balance of coverage and capacity, making them well-suited for providing coverage in urban areas.
High-band wireless spectrum refers to frequencies above 6 GHz, such as the millimeter wave (mmWave) bands. These frequencies have the advantage of being able to support very high data rates, making them well-suited for providing capacity in densely populated areas.
Low-band wireless spectrum has the advantage of providing good coverage and penetration, but the disadvantage of being subject to more interference and having lower data rates. High-band wireless spectrum has the advantage of providing high data rates and capacity, but the disadvantage of having limited coverage and being subject to more atmospheric absorption. Mid-band wireless spectrum offers a balance of coverage and capacity, but the disadvantage of being more expensive than low-band and less capable than high-band.
As a general rule of thumb, low-band spectrum is good for wide coverage, mid-band spectrum is good for balance of coverage and capacity, high-band spectrum is good for high data rates and capacity, but it is not as widely available and expensive.
Image source: T-Mobile