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.