Search results

is given a different frequency, so they do not interfere with one another. At the cable source or headend, electronic upconverters convert each incoming...

A block upconverter (BUC) is used in the transmission (uplink) of satellite signals. It converts a band of frequencies from a lower frequency to a higher...

effects of varying conditions on radio propagation has many practical applications, from choosing frequencies for amateur radio communications, international...

millimeter, corresponding to frequencies between 300 MHz and 300 GHz, broadly construed. A more common definition in radio-frequency engineering is the range...

frequency by switching calls to the nearest available cellular tower having that frequency available. This strategy is viable because a given radio frequency...

increase efficiency.(pp 77–78) AM radio broadcasting began around 1920. The allocation of the medium wave frequencies for broadcasting raised the possibility...

In radio communication, a spurious emission is any component of a radiated radio frequency signal the complete suppression of which would not impair the...

directly to L band. In most cases, frequency has to be converted using an upconverter before amplification and transmission. A modulated signal is a sequence...

gathering SNG, satellite internet access or VSAT applications) a block upconverter (BUC) connects via a waveguide to the feedhorn, in order to transmit...

garage door openers, and baby monitors use other frequencies in this same frequency range. Radio waves decrease rapidly in intensity by the inverse...

multi-element, directional antenna designed to operate over a wide band of frequencies. It was invented by John Dunlavy in 1952. The most common form of log-periodic...

A reconfigurable antenna is an antenna capable of modifying its frequency and radiation properties dynamically, in a controlled and reversible manner...

frequency of up to 60 GHz in his experiments. He also introduced the use of semiconductor junctions to detect radio waves, when he patented the radio...

Rumsey, V.H. (1957). "Frequency Independent Antennas". IRE International Convention Record. Vol. 5. New York, NY: Institute of Radio Engineers. p. 114-118...

Heavy-duty ham rotators are designed to turn extremely large, heavy, high frequency (shortwave) beam antennas, and cost hundreds or possibly thousands of...

in radio-frequency circuits". Brown Boveri Review, September 1944: 329–329. Sevick, Jerry (W2FMI). Transmission Line Transformer, The American Radio Relay...

least a quarter of the wavelength (⁠ 1 /4⁠ λ) of the radio waves in radius. In lower frequency antennas, such as the mast radiators used for broadcast...

Hidetsugu (September 1925). "On the Measurement of Natural Frequency of Coils with Ultra-radio Waves". The Journal of the Institute of Electrical Engineers...

in this section, the radio's operating frequency is assumed to be tuned to the loop antenna's first resonance. At that frequency, one whole free-space...

by the radio frequency current from the transmitter, and is the source of the radio waves. In a receiving antenna it collects the incoming radio waves...