[20220214]IF12046_国家频谱政策：5G环境下的干扰问题.pdf

https:/crsreports.congress.gov February 14, 2022National Spectrum Policy: Interference Issues in the 5G ContextRadio Spectrum as a National Resource Most wireless technologies, including mobile communications, radionavigation systems (e.g., the Global Positioning System, GPS), radar systems, satellites, and radio and television broadcasting, rely on a range of frequencies of electromagnetic radiation to transmit signals and data. Radio spectrum is the continuum of frequencies allocated for various radiocommunication services. Spectrum is an invisible, vital, and limited resource for the nations economic well-being, security, science, and safety. The Code of Federal Regulations specifies frequency allocations between 8.3 kilohertz (kHz) and 275 gigahertz (GHz). This portion of the spectrum is divided into about 800 bands (or groups of frequencies) for over 30 types of communication services, based on frequency characteristics. Some frequencies can travel long distances and penetrate seawater, making them useful for land-to-submarine communications. Other frequencies can travel a few miles and penetrate obstacles (e.g., buildings), making them useful for mobile communications. Radio