Coupling Loop

coupling loop

[′kəp·liŋ ‚lüp]
A conducting loop projecting into a waveguide or cavity resonator, designed to transfer energy to or from an external circuit.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Coupling Loop


in microwave engineering, a section of transmission line of specified length that is used as the coupling link in loop-type directional couplers. A coupling loop is regarded as a type of four-terminal network with specified parameters. In the designing of loop-type directional couplers, the lengths and the characteristic impedance of coupling loops are calculated, together with certain other parameters that provide the required operating characteristics of such couplers-—namely, the required directivity and isolation—in the frequency band used.


See references under STUB.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
First, a helix structure of resonant length excited through a primary coupling loop was used on both the transmitter and the receiver.
Because the voltage induced into a coupling loop is a function of the frequency, loop area, and circuit bandwidth, keep wide bandwidth loop areas small.
For a unit current, this is then equal to the mutual inductance between the coupling loop and the nth mode.
Mutual inductance or the magnetic flux through the coupling loop plays an important role in the analysis of the coupling.
A second tuner is used for matching the coupling loop to 50 |ohms~.
The output coupling loop and the piston used for matching it were not accounted for in the model.
|beta.sub.l1~ = the electrical length from the coupling loop short circuit to the start of coupling along the loop (rad)
|beta.sub.l2~ = the electrical length from the coupling loop short circuit to the end of coupling along the loop (rad)
Then using Equation 7, for the ferrite whose 4[pi][M.sub.s] value and diameter are known, the coupling loop diameter for the input, output and interstages can be calculated.
What now remains in the design is the calculation of the terminating lengths, [l.sub.o], [l.sub.n] and the launcher coupling loop.
Figure 1 shows the proposed WPTL where e is the distance between coupling loops and resonators, c is the transmission distance and r the radius of the coupling loops and resonators.
The dielectric rod resonator is used widely to measure the dielectric properties of high permittivity and low loss dielectric resonators in the microwave region.[2-4] For the measurement of relative permittivity [[Epsilon].sub.r][prime], a high accuracy of 0.1 percent can be obtained using this method.[4] However, it is necessary to design the measured sample's configuration and coupling loops carefully due to the many resonant modes in the dielectric resonator.[5,6] Furthermore, it is important to separate the different resonant modes in the measurement process.