"A",
"B",
"C",
"D",
"E",
"F",
"G"/"H",
"I"/"J"/"K"/"L",
"M"/"N"/"O",
"P"/"Q",
"R",
"S",
"T",
"U"/"V"/"W"/"X"/"Y"/"Z"
Fading: A periodic decrease or increase in the received signal strength. Variations in signal strength by atmospheric conditions.
Fan Beam Antenna: -- Text in Review.
Fan Beam Antenna
Feeder: A transmission line that carries energy to the antenna.
Feedpoint impedance: Impedance that is measured at the input terminals of an electrical device such as an antenna.
Fields: Regions in which each point has a value of a physical quantity (voltage, magnetic force, velocity, mass, etc.).
Flexible Coaxial Line: A coaxial line made with a flexible inner conductor insulated from the outer conductor by a solid, continuous insulating material. Also refer to the related terms; Definition of Coaxial Cable, Coax [located within the Dictionary of Radar terms].
Folded Dipole: An ordinary half-wave antenna (dipole) that has one or more additional conductors connected across the ends parallel to each other.
Four-Element Array: An array with three parasitic elements and one driven element.
Free space: The absence of matter.
Free space loss: The loss of energy of a radio wave because of the spreading of the wavefront as it travels from the transmitter.
Frequency: The rate at which a process repeats itself. In radio communications, frequency is expressed in Hz.
Frequency hopping: A method of jumping from frequency to frequency in synchronization with one another in a random order at a rate of up to 100 times per second.
Frequency Modulation: [FM] The process of varying the frequency of a carrier wave, usually with an audio frequency, in order to convey intelligence.
Frequency of optimum transmission: 85 percent of the Maximum Usable Frequency (MUF). A practical frequency selection which allows for MUF variations.
