Band (radio) in the context of "Electromagnetic interference"

A ground station, Earth station, or Earth terminal is a terrestrial radio station designed for extraplanetary telecommunication with spacecraft (constituting part of the ground segment of the spacecraft system), or reception of radio waves from astronomical radio sources. Ground stations may be located either on the surface of the Earth, or in its atmosphere. Earth stations communicate with spacecraft by transmitting and receiving radio waves in the super high frequency (SHF) or extremely high frequency (EHF) bands (e.g. microwaves). When a ground station successfully transmits radio waves to a spacecraft (or vice versa), it establishes a telecommunications link. A principal telecommunications device of the ground station is the parabolic antenna.

Ground stations may have either a fixed or itinerant position. Article 1 § III of the International Telecommunication Union (ITU) Radio Regulations describes various types of stationary and mobile ground stations, and their interrelationships.

An antenna farm, satellite dish farm or dish farm is an area dedicated to television or radio telecommunications transmitting or receiving antenna equipment, such as C, K_u or K_a band satellite dish antennas, UHF/VHF/AM/FM transmitter towers or mobile cell towers. The history of the term "antenna farm" is uncertain, but it dates to at least the 1950s.

In telecom circles, any area with more than three antennas could be referred to as an antenna farm. In the case of an AM broadcasting station (mediumwave and longwave, occasionally shortwave), the multiple mast radiators may all be part of an antenna system for a single station, while for VHF and UHF the site may be under joint management. Alternatively, a single tower with many separate antennas is often called a "candelabra tower".

UHF CB is a class-licensed citizen's band radio service authorised by the governments of Australia, Europe, Malaysia, New Zealand, Singapore, Vanuatu, and in the PMR446, UHF 477 MHz band. UHF CB provides 77 channels, including 32 channels (16 output, 16 input) allocated to repeater stations. It is similar in concept to the General Mobile Radio Service in the United States.

A stopband is a band of frequencies, between specified limits, through which a circuit, such as a filter or telephone circuit, does not allow signals to pass, or the attenuation is above the required stopband attenuation level. Depending on application, the required attenuation within the stopband may typically be a value between 20 and 120 dB higher than the nominal passband attenuation, which often is 0 dB.

The lower and upper limiting frequencies, also denoted lower and upper stopband corner frequencies, are the frequencies where the stopband and the transition bands meet in a filter specification. The stopband of a low-pass filter is the frequencies from the stopband corner frequency (which is slightly higher than the passband 3 dB cut-off frequency) up to the infinite frequency. The stopband of a high-pass filter consists of the frequencies from 0 hertz to a stopband corner frequency (slightly lower than the passband cut-off frequency).