In this study, a new simple method for design and implementation of RECTANGULAR WAVEGUIDE leaky wave antenna with the longitudinal long slot is presented. In this method which has been done using HFSS, firstly, the WAVEGUIDE attenuation is calculated based on the position of the slot in relation to the WAVEGUIDE broad wall. Then the desired aperture illumination is fitted to the slot position on the broad wall of the WAVEGUIDE by MATLAB. Finally, a Taylor-distributed RECTANGULAR WAVEGUIDE leaky wave antenna with 30 dB SLL designed and fabricated in ku band. The good agreement between the simulation and the measurement results for radiated patterns verifies the effectiveness of the presented method.

The characteristics of dielectric backed planar conducting layers of arbitrarily shaped in a RECTANGULAR WAVEGUIDE are calculated by means of coupled integral equation technique (CIET) which accurately takes higher order mode interactions. Spectral dyadic green’s functions are derived for these equivalent structures. A coupled magnetic-filed integral equation formulation is proposed which is solved using method of moment (MoM).Then one matrix equation that involves the all magnetic currents of non-metallic parts (aperture parts) of discontinuities is derived. This single matrix formulation replaces the procedure of cascading individual GSM’s of each block. By dividing the area of cross section in discontinuities into a given number of subsections, it is possible to model any shape of metallic parts. The proposed technique permits modeling of a variety of structures such as cavity-backed micro strip antenna, frequency selective surfaces (FSS’s), WAVEGUIDE filters with printed irises and generally multilayered media with printed circuits embedded between dielectric layers in a WAVEGUIDE.The usefulness of the proposed method and its performance are verified by calculating and simulating of a given structure.

In this paper, the modal analysis is used to study the behavior of a RECTANGULAR WAVEGUIDE loaded with a transversely thin conductive discontinuity. To this end, a function must be made according to the geometry of discontinuity. This function is utilized instead of applying boundary conditions on the plane where the discontinuity is. This equation includes all the necessary boundary conditions simultaneously. The scattering parameters of the structure are related to the coefficients of the Fourier series of the newly defined function. Then, the return loss and insertion loss of different structures are investigated while the geometrical parameters of discontinuity take different values. The behavior of structures can be explained by how dense the coefficients of the Fourier series are. The simulation results show that the error of this technique is less than 2%. This analysis can enable designers to understand how the geometrical parameters of discontinuity affect the scattering parameters for an H-plane inductive diaphragm.

The aim of the present study is to determine the feasibility of making a RECTANGULAR twist WAVEGUIDE used to rotate electromagnetic waves. For this purpose, the process of fabricating an aluminum RECTANGULAR twist WAVEGUIDE was simulated by making use of finite element method and Deform software. The optimum length and angle of the twist die for manufacturing a twist WAVEGUIDE with inner cross sectional dimensions of 22. 86 mm × 10. 16 mm and a length of 50 mm and twisting angle of 90 degrees were investigated. Moreover, the effect of certain factors such as the length, thickness, cross section dimensions of the WAVEGUIDE and friction on the optimum length of the twist die and cross sectional distortion was studied. The results of this study indicated that the length of the twist die had an influence on the amount of twisting, while friction was of no importance. In addition, comparing the values of effective stress and flow stress at the cross section of the workpiece behind the twist die depicted that the workpiece would not yield behind the twist die due to smaller values of effective stress.

In this paper, a novel WAVEGUIDE array antenna composed of non-inclined slots in the narrow wall of the WAVEGUIDE, which are excited with RECTANGULAR Iris is introduced. This new method in addition to improving impedance and radiation characteristics has an easy production process. Also, because of using non-inclined slots, the antenna has very low cross polarization level. In this paper, in the first step, suitable radiating elements for designing a linear slot array antenna were considered, and then a linear array suitable surveillance radar with 136 elements with Taylor distribution is designed and simulated with HFSS at the frequency of (2.7 - 3.1) GHz. Finally, the antenna has been fabricated and tested. The results of the test and simulation are in good agreement.

WAVEGUIDEs, used in electronic industries, are structures for transferring electromagnetic waves. A twist WAVEGUIDE is a device used to change the polarization of waves. In this study, a process for fabricating an aluminum RECTANGULAR twist WAVEGUIDE was designed and some guidelines were introduced. The preliminary profile was obtained by a forward extrusion process. In order to study the effect of strain hardening, the twisting process was studied for annealed and non-annealed samples after the extrusion process. The results revealed the necessity of annealing the samples before the twisting; otherwise, local deformation would occur. Measuring the applied torque showed that as the process progressed, the required torque for an annealed sample would increase due to work hardening, while for a non-annealed sample the torque would decrease after local deformation. Furthermore, the simulation of twisting process was performed using Deform software. No inconsistency was observed between numerical and experimental results. Moreover, investigating the cross sectional distortion showed an undesirable cross sectional distortion for the unfilled sample whereas the cross section in the sand-filled sample stayed RECTANGULAR.

A metallic coupler is proposed to interface a silicon on insulator (SOI) WAVEGUIDE with a narrow hybrid plasmonic WAVEGUIDE (200× 200 nm). The device operation is investigated and optimized to attain the best tradeoff between the mode confinement and the propagation loss. Calculations reveal that a high confinement and low loss of the energy is achieved from a silicon slab WAVEGUIDE into the dielectric slot of area 200×200 nm2 and a coupling efficiency of 70% (0.8 dB) at the 1.55 mm telecommunication wavelength can be achieved.

In this research, in order to investigate the effect of the piezoelectric patch which is used as a sensor or actuator in rotating flexible structures such as a helicopter blade, the free vibrations of the rotating RECTANGULAR sheet with and without the piezoelectric patch have been presented. First-order shear deformation theory is considered for plate displacement and piezoelectric field. Considering the effect of Coriolis acceleration, centrifugal acceleration and centrifugal in-plane forces, the equations of motion are derived from Hamilton's principle and the electromechanical couple equation is obtained from Maxwell's equation. For piezoelectric, two electrical conditions, open circuit and closed circuit, which are used in sensors and actuators, respectively, have been considered. The equations are discretized with the help of the numerical method of generalized differential squares and the matrices of inertia mass, eccentricity, Coriolis and stiffness matrix are obtained. Natural frequency values for beam and rotating plate have been compared in Abaqus software. Also, the values obtained from the numerical solution in MATLAB have been verified with articles and ABAQUS, which have high accuracy. The effect of parameters such as hub radius, rotation speed, sheet thickness, aspect ratio, piezoelectric patch thickness and applied voltage on the natural frequency of the system has also been investigated.