Antenna Dictionary
"A",
"B",
"C",
"D",
"E",
"F",
"G"/"H",
"I"/"J"/"K"/"L",
"M"/"N"/"O",
"P"/"Q",
"R",
"S",
"T",
"U" to "Z"
UHF: Refer to Ultrahigh frequency. Details on Frequency Bands.
Ultrahigh frequency: [UHF] Frequencies between 300 and 3,000 MHz. Used for TV channels 14-51 [470MHz to 698MHz]
Umbrella Antenna. An antenna atop a mask that uses guy-wires to wire elements are pulled downward from the central mask resembling an umbrella, used for transmission in the LF and VLF frequency ranges.
Unbalanced transmission line: A transmission line one of whose conductors is grounded.
Unidirectional: In one direction only.
Unidirectional Array: An array that radiates in only one general direction.
Uniform Linear Array: An antenna composed of a relatively large number of usually identical elements
arranged in a single line or in a plane with uniform spacing and usually with a uniform feed system.
Unmodulated Carrier: The portion of a carrier wave that contains no intelligence.
V Antenna. A bidirectional antenna, shaped like a V, which is widely used for communications. An antenna whose elements are in the shape of a 'V' [see graphic below]. Also refer to the listing of Antenna Manufacturers.
Vee Antenna: Two long-wire antennas connected to form a V. A directional antenna.
Velocity: The speed of a radio wave through the dielectric medium
it is in.
Vertical dipole: A balanced or dipole antenna oriented vertically.
Vertical Gain: The gain of the antenna in the vertical (overhead) direction.
Vertical polarization: [vertically-polarized] Transmission of radio waves in such a way
that the electric lines of force are vertical (perpendicular) to the Earths surface.
Vertical quarter-wave antenna: A monopole (whip) antenna that
is oriented vertically.
Vertical Whip: See whip antenna.
Very high frequency: [VHF] Frequencies between 30 and 300 MHz;
transmissions that follow the line of sight path. Used for TV channels 2-13 [54MHz to 216MHz]
Voltage: Electrical pressure, expressed in volts, which is the result
of squeezing electrons together.
Voltage standing-wave ratio: [VSWR] The ratio of the amplitude of the
electric field or voltage at a voltage maximum to that at an adjacent voltage minimum.
Wave Antenna. Same as Beverage Antenna.
Waveguide: A hollow metal tube used as a transmission line to guide energy from one point to another. [WaveGuide Manufacturers]
Wavelength: The distance a wave travels during one complete
cycle. It is equal to the velocity divided by the frequency.
Wave Propagation: The transmission of RF energy through space.
Whip antenna: A vertical monopole. A flexible rod antenna, usually
between 1/10 and 5/8 wavelength long, supported on
a base insulator. [Antenna Manufacturers]. |
 Whip Antenna |
Wind Load: The wind speed the antenna is capable of withstanding.
Wire: Conductors in one of many different sizes with different
kinds of insulation. [Wire Manufacturers]
Wire Rope Antenna: A wire rope antenna consists of one or more lengths of flexible wire rigged from two or
more points and used as either a receiving antenna or transmitting antenna. If used on a ship, a wire rope antenna is strung either vertically or horizontally from a yardarm or mast to outriggers, another mast, or to the superstructure. Also the antenna maybe specifically designed for a particular ship, as the superstructure and other nearby structures become an electronically integral part of the antenna.
Wullenweber Antenna. An antenna array that uses two concentric circles of antenna arrays.
Wullenweber Antenna Array
X-Band. A range of frequencies between 8GHz and 12GHz. X-Band in detail.
X-Y Mount: A style of antenna mounting that uses the X-axis as the primary mount and the Y-axis as the secondary mount. The Radar Dictionary shows a graphic of an X-Y Antenna Mount.
Yagi Antenna. A multi-element parasitic array. The elements lie in the same plane as those of the end-fire array. A linear end-fire antenna, consisting of three or more half-wave elements (one driven, one reflector, and one or more directors). A Yagi antenna offers very high directivity and gain. The formal name for a Yagi antenna is Yagi-Uda array.
Yagi Reflector
Y-Match. A method of connecting to a Dipole antenna, see Dipole for a graphic.
Zeppelin Antenna: Text in review. A type of antenna.
