An adaptable measurement method is proposed for the frequency-dependency of the complex permittivity of the materials with low or high losses based on the rigorous hybrid electromagnetic method. Both transmission and ...
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ISBN:
(纸本)9781479914340;9781479914326
An adaptable measurement method is proposed for the frequency-dependency of the complex permittivity of the materials with low or high losses based on the rigorous hybrid electromagnetic method. Both transmission and reflection measurement methods are developed using the X-band waveguides. The validity of the methods is confirmed by virtual experiments and actual measurements.
In this paper the methods and algorithms for electrodynamic analysis and synthesis of mode converters based on ridged rectangular waveguides are considered. Electromagnetic fields and cutoff wave numbers of ridged rec...
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ISBN:
(纸本)9781467344784;9781467344791
In this paper the methods and algorithms for electrodynamic analysis and synthesis of mode converters based on ridged rectangular waveguides are considered. Electromagnetic fields and cutoff wave numbers of ridged rectangular waveguides are calculated by the method of partial regions including field singularities at the edge. The method of cross sections with smooth geometry variation is used for mode converter construction. The main difference and advantage over the known mode converter geometries that the only ridge dimensions and position in the waveguide is a subject to smooth variation while the basis rectangular waveguide remains regular.
The IEC has suggested that maximum allowable displacements of waveguide flanges should not cause the inherent return loss due to waveguide tolerances to degrade more than 1 dB. Calculations on displaced unequal wavegu...
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The IEC has suggested that maximum allowable displacements of waveguide flanges should not cause the inherent return loss due to waveguide tolerances to degrade more than 1 dB. Calculations on displaced unequal waveguides at their extreme tolerances show that this leads to a maximum allowable displacement of 0.0175 of the broad (= a) dimension for a waveguide tolerance of /spl plusmn/ a/500. The worst return loss under these conditions is approximately -41dB. However, it is suggested that this maximum allowable displacement is based on a statistically remote worse case condition, and relaxation to a value of 0.021a would be more realistic.
An arbitrary shaped crosssectional discontinuity in rectangular waveguides is investigated using FEM-BIM with triangular prism elements, which is more effective than normal FEM. The volume of discontinuity is subdivid...
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ISBN:
(纸本)0780341783
An arbitrary shaped crosssectional discontinuity in rectangular waveguides is investigated using FEM-BIM with triangular prism elements, which is more effective than normal FEM. The volume of discontinuity is subdivided into a relatively small number of triangular prism elements and FEM is used to formulate the field distribution. On the other hand, the fields in the waveguide region are represented by BIM derived from the waveguide Green's function and boundary conditions. The proposed method is verified through the experiment for the circular iris in WR-90 waveguide.
Reciprocal and nonreciprocal propagation of electromagnetic energy in an infinitely long rectangular waveguide partially filled with one or two ferrite slabs is described. Methods for obtaining exact solutions of the ...
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A left-handed rectangular waveguide periodically filled with tangentially magnetized ferrite medium has been proposed, and backward wave characteristics in the structure have been confirmed numerically by using a mode...
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ISBN:
(纸本)0780390091
A left-handed rectangular waveguide periodically filled with tangentially magnetized ferrite medium has been proposed, and backward wave characteristics in the structure have been confirmed numerically by using a mode-matching method. The operational frequency is selected to be below the cutoff frequency for a dominant TE10 mode in a rectangular waveguide where the effective permittivity is negative. The obtained results show that there exist backward-wave modes in the negative permeability frequency region where magnetostatic surface wave modes can be supported, and the field profiles have a sinusoid-like form composed of a series of exponentials in each section. In addition, three-dimensional full-wave simulation is demonstrated, which shows that unexpected excitations of magnetostatic surface wave mode transversely propagating along a surface of the ferrite layer near the input port plays a role of a transformer from a guided TE10 mode to the backward wave mode and vice versa near the output port.
Based on our previous work, a brief description of the theory of using TE and TM modes to determine the permittivity of nonmagnetic uniaxial anisotropic media without changing the position of the sample is presented. ...
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ISBN:
(纸本)9798350371611;9788396972613
Based on our previous work, a brief description of the theory of using TE and TM modes to determine the permittivity of nonmagnetic uniaxial anisotropic media without changing the position of the sample is presented. The extraction procedure is based on the use of two pairs of reflection coefficients and propagation coefficients in a manner similar to the classical Nicolson-Ross-Weir method for isotropic media. The obtained simulation results for an artificial uniaxial anisotropic dielectric material constitute a promising basis for experimental research.
Single-mode 75 gm x 37 gm rectangular waveguide components, including horn antennas, couplers, and bends, for operation at 3 THz have been designed and fabricated using thick gold micromachining. THz transmission thro...
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ISBN:
(纸本)9781424420414
Single-mode 75 gm x 37 gm rectangular waveguide components, including horn antennas, couplers, and bends, for operation at 3 THz have been designed and fabricated using thick gold micromachining. THz transmission through these waveguides has been quasi-optically measured at 2.92 THz. This technology offers the potential for realizing miniature integrated systems operating in the 3 THz frequency range.
The work deals with investigation of electromagnetic waves scattering on the slot systems in rectangular waveguides with arbitrary end loads. The linear slotted-guide gratings with slot elements of different kinds, su...
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ISBN:
(纸本)2960055128
The work deals with investigation of electromagnetic waves scattering on the slot systems in rectangular waveguides with arbitrary end loads. The linear slotted-guide gratings with slot elements of different kinds, such as longitudinal slots, doubled ones and cross-like slots, are considered. The influence of inner and external mutual coupling and finite wall thickness are taken into account. The solution of the problem under consideration is based on improved and specially modified well-known method of successive approximations.
The structure consisting of an E-plane dielectric slab partially filling a rectangular waveguide is examined with attention on those higher order mode propagation characteristics that are relevant to the design of non...
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