The wavenumber is a scalar quantity that only depends on the frequency in question, and specifies the phase change per meter for a wave. The quantity (often denoted k or sometimes as ) is given in rad ...
In the case of a coaxial cable feeding an antenna, a balun is used to choke (eliminate or reduce) the currents flowing on the outside shield of the coaxial cable.
The idea of an Infinite Balun is ...
For a radio (transmitter or receiver) to deliver power to an antenna, the impedance of the radio and transmission line must be well matched to the antenna's impedance. The parameter VSWR is a measure ...
The H-plane is a plane that contains the H-field and the direction of maximum radiation from the antenna. As an example, consider a short dipole, the magnetic fields are given by:
This states tha ...
Total Radiated Power (TRP) is a measure of how much power is radiated by an antenna when the antenna is connected to an actual radio (or transmitter). TRP is an active measurement, in that a powered t ...
The Front-to-Back Ratio is a parameter used in describing directional radiation patterns for antennas. If an antenna has a unique maximum direction, the front-to-back ratio is the ratio of the gain in ...
Total Isotropic Sensitivity (TIS) is a commonly quoted specification in the mobile phone industry. This, like Total Radiated Power (TRP) is a parameter that depends on the antenna and the receiver (or ...
The fractional bandwidth of an antenna is a measure of how wideband the antenna is. If the antenna operates at center frequency fc between lower frequency f1 and upper frequency f2 (where fc=(f1+f2)/2 ...
The principle of operation of a Tapered Balun is presented on this page. This balun is simple to understand - it gradually changes the shape of an unbalanced transmission line to that of a balanced li ...
The principle of operation of a Folded Balun is presented on this page (this balun is sometimes called the quarter-wavelength balun). This balun draws a cancelling current from the central arm of the ...
A steering vector represents the set of phase delays a plane wave experiences, evaluated at a set of array elements (antennas). The phases are specified with respect to an arbitrary origin.
For insta ...
EVM (Error Vector Magnitude) is a measure of how accurately a radio is transmitting symbols within its constellation. EVM is a measure of signal quality, which is a function of noise, interfering sign ...
Understanding Spherical Coordinates is a must for the practicing antenna engineer. You are probably familiar with Cartesian Coordinates - a position (point P) can be specified by a triplet like (x,y,z ...
The Electric Flux Density (usually written as the vector quantity D) is often used in electromagnetics. While we won't give it a rigorous definition here, it can be sufficiently understood for the pur ...
Specific Absorption Rate (or SAR) is a measure of how transmitted RF energy is absorbed by human tissue. SAR is a function of the electrical conductivity (, measured in Siemens/meter), the induced E-f ...
