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Figure from:A metamaterial surface for compact cavity resonators

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Fig. 3. (a) Geometry of the waveguide loaded with the metamaterial slab (a = 15 mm, 6 = 5 mm). (b) Equimagnitude lines of the E’'y field at the resonant frequency f = 1.41 GHz.

Figure 3 (a) Geometry of the waveguide loaded with the metamaterial slab (a = 15 mm, 6 = 5 mm). (b) Equimagnitude lines of the E’'y field at the resonant frequency f = 1.41 GHz.

Related Figures (6)

Fig. 1. Geometry of a gangbuster-FSS printed on a dielectric slab. h = 0.508 mm, w = 0.25 mm, d, = 10 mm, 6 = 0.2 mm, d, = 0.5 mm, relative permittivity of the slab ¢, = 4.5. Dipoles are printed on both sides of the dielectric slab. Inset at the left: transverse cross section showing the offset of dipoles placed at the same z-level. (b) Equivalent x-transmission line circuit network. Marco Caiazzo, Student Member, IEEE, Stefano Maci, Fellow, IEEE, and Nader Engheta, Fellow, IEEE
Fig. 1. Geometry of a gangbuster-FSS printed on a dielectric slab. h = 0.508 mm, w = 0.25 mm, d, = 10 mm, 6 = 0.2 mm, d, = 0.5 mm, relative permittivity of the slab ¢, = 4.5. Dipoles are printed on both sides of the dielectric slab. Inset at the left: transverse cross section showing the offset of dipoles placed at the same z-level. (b) Equivalent x-transmission line circuit network. Marco Caiazzo, Student Member, IEEE, Stefano Maci, Fellow, IEEE, and Nader Engheta, Fellow, IEEE
Fig. 2. (a) Geometry of 1-D cavity resonator (@ = 15 mm) and schematic profile of the dominant electric field along the y axis. At the right hand side, an analogy with a short dipole loaded with lumped inductances at the delta gap is shown. (b) Equivalent x-transmission line network (left-hand side) and its corresponding impedances as observed at the midpoint section (right-hand side).
Fig. 2. (a) Geometry of 1-D cavity resonator (@ = 15 mm) and schematic profile of the dominant electric field along the y axis. At the right hand side, an analogy with a short dipole loaded with lumped inductances at the delta gap is shown. (b) Equivalent x-transmission line network (left-hand side) and its corresponding impedances as observed at the midpoint section (right-hand side).
Fig. 4. Equivalent dispersive x-transmission line circuit network (left) and corresponding impedances as observed at the mid point section (right).
Fig. 4. Equivalent dispersive x-transmission line circuit network (left) and corresponding impedances as observed at the mid point section (right).
Fig.5. Dispersion curves ( f —k.) of the metamaterial-slab-loaded waveguide for different size a. Continuous line and dotted lines refer to result from CST and from (5), respectively. Dashed line is relevant to the dispersion curve of the first surface wave TE mode of the metamaterial thin slab. The horizontal axis exhibits a second scale, which serves to find the resonant frequency of a 3-D cavity with length W. The cross-sectional field distribution insets show how the fields decreases for different point along the dispersion curve. As one gets farther away from the light line, the field decays more rapidly.
Fig.5. Dispersion curves ( f —k.) of the metamaterial-slab-loaded waveguide for different size a. Continuous line and dotted lines refer to result from CST and from (5), respectively. Dashed line is relevant to the dispersion curve of the first surface wave TE mode of the metamaterial thin slab. The horizontal axis exhibits a second scale, which serves to find the resonant frequency of a 3-D cavity with length W. The cross-sectional field distribution insets show how the fields decreases for different point along the dispersion curve. As one gets farther away from the light line, the field decays more rapidly.
A corresponding 3-D compact resonator can be obtained by inserting two additional PEC walls a distance W apart and or- thogonal to the z-direction inside the loaded waveguide (Fig. 6). The first resonance of this 3-D cavity resonator is found by im- posing 7/W = kz, that is by assuming the cavity length being one half of the slow-wave mode’s wavelength. From (5), this leads to where Wye; 1s the resonant frequency of this 3-D resonator. (The graphical interpretation may be deduced from Fig. 5 reading
A corresponding 3-D compact resonator can be obtained by inserting two additional PEC walls a distance W apart and or- thogonal to the z-direction inside the loaded waveguide (Fig. 6). The first resonance of this 3-D cavity resonator is found by im- posing 7/W = kz, that is by assuming the cavity length being one half of the slow-wave mode’s wavelength. From (5), this leads to where Wye; 1s the resonant frequency of this 3-D resonator. (The graphical interpretation may be deduced from Fig. 5 reading
Fig. 6. Geometry of a 3-D resonator, and modal Fy-field distributions in three cross-sectional planes, at the frequency of 1.866 GHz. Dimensions: axbxW = 15 x 5 x 15 mm. metamaterial FSS slab interact significantly with the side walls. Starting from a cut-off frequency, as the frequency increases, the dispersion curves crosses the light-line (dashed line), and then moves toward the slow-wave region. Beyond the light line, the dominant FW associated with the metamaterial thin slab is evanescent, along x. The dispersion equation (4) may be conve- niently rewritten as
Fig. 6. Geometry of a 3-D resonator, and modal Fy-field distributions in three cross-sectional planes, at the frequency of 1.866 GHz. Dimensions: axbxW = 15 x 5 x 15 mm. metamaterial FSS slab interact significantly with the side walls. Starting from a cut-off frequency, as the frequency increases, the dispersion curves crosses the light-line (dashed line), and then moves toward the slow-wave region. Beyond the light line, the dominant FW associated with the metamaterial thin slab is evanescent, along x. The dispersion equation (4) may be conve- niently rewritten as