Ads
related to: copper electronics antennas
Search results
Results from the WOW.Com Content Network
Counterpoises are typically used in antenna systems for radio transmitters where a good earth ground connection cannot be constructed.. Monopole antennas used at low frequencies, below 3 MHz, such as the mast radiator antennas used for AM broadcasting, require the radio transmitter to be electrically connected to the Earth under the antenna; this is called a ground (or earth).
The category of simple antennas consists of dipoles, monopoles, and loop antennas. Nearly all can be made with a single segment of wire (ignoring the break made in the wire for the feedline connection). [citation needed] Dipoles and monopoles called linear antennas (or straight wire antennas) since their radiating parts lie along a single ...
The antenna gain, or power gain of an antenna is defined as the ratio of the intensity (power per unit surface area) radiated by the antenna in the direction of its maximum output, at an arbitrary distance, divided by the intensity radiated at the same distance by a hypothetical isotropic antenna which radiates equal power in all directions.
For a monopole antenna (a), the Earth acts as a ground plane to reflect radio waves directed downwards, making them seem to come from a virtual "image antenna" (b).In Telecommunications, a ground plane is a flat or nearly flat horizontal conducting surface that serves as part of an antenna, to reflect the radio waves from the other antenna elements.
A patch antenna is a type of antenna with a low profile, usually consisting of a printed circuit board. It consists of a planar rectangular or circular sheet or "patch" of metal, mounted over a larger sheet of metal called a ground plane. It is the original type of microstrip antenna described by Howell in 1972. [1]
Discone made of solid copper sheets, theoretically covering 700 MHz to 2 GHz. A discone antenna is a monopole version of a biconical antenna, in which one of the cones is replaced by a disc. It is usually mounted vertically, with the disc at the top and the cone beneath.
For antennas near a half-wavelength high (180 electrical degrees [b]) the antenna has a voltage maximum near its base, which results in strong electric fields in the earth above the ground wires near the mast where the displacement current enters the ground. To reduce this loss these antennas often use a conductive copper ground screen under ...
A spiral antenna is a type of radio frequency antenna shaped as a spiral, [1]: 14‑2 first described in 1956. [2] Archimedean spiral antennas are the most popular, while logarithmic spiral antennas are independent of frequency: [3] the driving point impedance, radiation pattern and polarization of such antennas remain unchanged over a large bandwidth. [4]
Ads
related to: copper electronics antennas