Search results
Results From The WOW.Com Content Network
The G5RV antenna is a dipole antenna fed indirectly, through a carefully chosen length of 300 Ω or 450 Ω twin lead, which acts as an impedance matching network to connect (through a balun) to a standard 50 Ω coaxial transmission line. The sloper antenna is a slanted vertical dipole antenna attached to the top of a single tower. The element ...
Metamaterial antenna. This Z antenna tested at the National Institute of Standards and Technology is smaller than a standard antenna with comparable properties. Its high efficiency is derived from the "Z element" inside the square that acts as a metamaterial, greatly boosting the radiated signal. The square is 30 millimeters on a side.
Radiation efficiency is defined as "The ratio of the total power radiated by an antenna to the net power accepted by the antenna from the connected transmitter." [1] It is sometimes expressed as a percentage (less than 100), and is frequency dependent. It can also be described in decibels.
Dipole field strength in free space. Dipole field strength in free space, in telecommunications, is the electric field strength caused by a half wave dipole under ideal conditions. The actual field strength in terrestrial environments is calculated by empirical formulas based on this field strength.
Aperture (antenna) In electromagnetics and antenna theory, the aperture of an antenna is defined as "A surface, near or on an antenna, on which it is convenient to make assumptions regarding the field values for the purpose of computing fields at external points. The aperture is often taken as that portion of a plane surface near the antenna ...
The analogous quantity for a plane wave travelling through a dielectric medium is called the intrinsic impedance of the medium and designated η . Hence Z 0 is sometimes referred to as the intrinsic impedance of free space, [2] and given the symbol η 0. [3] It has numerous other synonyms, including: wave impedance of free space, [4]
Antenna measurement techniques refers to the testing of antennas to ensure that the antenna meets specifications or simply to characterize it. Typical parameters of antennas are gain, bandwidth, radiation pattern, beamwidth, polarization, and impedance. The antenna pattern is the response of the antenna to a plane wave incident from a given ...
Free-space path loss. In telecommunications, the free-space path loss (FSPL) (also known as free-space loss, FSL) is the attenuation of radio energy between the feedpoints of two antennas that results from the combination of the receiving antenna's capture area plus the obstacle-free, line-of-sight (LoS) path through free space (usually air). [1]