Radio Spectrum

- Overview

The radio spectrum is an important part of the larger electromagnetic spectrum, which includes not only radio waves, but also light, infrared and ultraviolet radiation, and several other forms of radiation. 

Understanding the electromagnetic spectrum and what different forms of radiation are and how they respond can help provide clues about how different forms of radiation behave. 

Likewise, understanding the radio spectrum and the different wavelengths and frequencies is key to understanding the characteristics of signals at different points in the spectrum. 

Different wavelengths and frequencies mean that the signal has different properties and can be used in different ways: long-distance radio communication, point-to-point radio communication, radio links that are safer because the signal travels farther, satellite communication links, etc. Many. Different frequencies and portions of the spectrum may be more suitable for one form of radio application than another.

Designations such as LF, MF, HF, VHF and UHF, EHF stand for the radio spectrum or part of the radio spectrum.

- ITU Frequency Band Names

The International Telecommunication Union (ITU) is a global organization that regulates the use of the radio spectrum. 

In order to be able to easily refer to different parts of the radio spectrum, the ITU divides the radio spectrum into 12 different frequency bands, numbered 1 to 12, and also gives the names.

Please refer to Wikipedia:Radio Spectrum for more details.

- Radio Frequency Band Characteristics and Applications

The radio frequency band covers a very broad frequency range. Therefore, there is a wide range of different properties they possess. This means that different RF bands are often used for very different applications. RF design is also done differently. 

Interestingly, above 300 GHz, the absorption of electromagnetic radiation by the Earth's atmosphere rises dramatically to the point where it becomes almost opaque. As the frequency increases into the near-infrared, it becomes transparent again, providing a window into these radiations and optical electromagnetic radiation. 

However, within the radio spectrum, each frequency band has a different purpose, from radio communications to broadcasting, satellite links, radar, mobile communications, WLAN, and more.

One of the main differences is how the radio signal travels. The ionosphere and troposphere contribute at different frequencies and to varying degrees. Atmospheric absorption also plays a role, especially at certain frequencies. 

Therefore, selecting the correct portion of the radio spectrum for a given application is critical to the successful deployment of a radio-based system, whether it is for radio communications, mobile communications, data links, radar, remote sensing, or many other applications.