A particle in a rectangular waveguide can be pulled towards the light source or pushed away from the light source just by varying the frequency around the waveguide cutoff frequency
. All of the graphical representations and calculations are accurate within the Rayleigh scattering regime, but may be inappropriate for a larger particle.
Firstly, the CSRRs have extraordinary property of generating forward wave transmission below the waveguide cutoff frequency
If D and the waveguide cutoff frequency
[[omega].sub.c] are known exactly, the value of the coefficients [C.sub.0], [C.sub.1], [C.sub.2] and [C.sub.3] that specify the open circuit can be calculated as the Mac Laurin series of the capacitance vs.
This close spacing dictates dielectric loading to lower the waveguide cutoff frequency
. Internal circular polarizers serve as these loads.
Figure 2 shows the computed coupling (all curves presented are normalized to the waveguide cutoff frequency
) and pertinent coupler parameters.
The typical dielectric resonator filter consists of ceramic resonator discs mounted in a metal cavity operating well below its waveguide cutoff frequency
. In this situation, the resonator basically behaves like a magnetic-walled waveguide, the dual of a waveguide cavity.