1. Introduction Leaky-wave antennas based on an open-waveguide structure can become a candidate of millimeter-wave antennas. Since such a structure is already open, leakage is produced by introducing not a physical cut, but asymmetry of the structure. As a result, it supports a leaky mode (instead of a bound mode) and therefore radiates all along its length, possess flexibility in beamwidth and...

[1] Green’s function analysis of an ideal hard surface rectangular waveguide is proposed for characterization of the modal spectrum of the structure. A decomposition of the hard surface waveguide into perfect electric conductor and perfect magnetic conductor waveguides allows the representation of dyadic Green’s function as a superposition of transverse magnetic (TM) and transverse electric (TE...

An essential impact which can improve the indoor environment and save on power consumption for artificial lighting is utilization of daylight. Optical fiber daylighting technology offers a way to use direct daylight for remote spaces in a building. However, the existing paradigm based on the precise orientation of sunlight concentrator toward the Sun is very costly and difficult to install on t...

In this paper the transmittance of metal-insulator-metal (MIM) waveguides containing semi-circular ring shaped and rectangular ring shaped grooves are investigated. By varying groove parameters their effects on the transmittance of the MIM waveguides are investigated. The results show that the transmittance spectra of the waveguides have maximum and minimum points, and by using appropriate para...

The TM0 surface mode in an infinitely long parallel-plate waveguide filled with a double-positive (DPS) and epsilon-negative (ENG) metamaterial bi-layer is studied. With proper constitutive parameters and thicknesses of the two layers, the slow-wave factor (SWF) for such a parallel-plate waveguide can tend to infinity as the frequency decreases. A 2-D cavity based on the DPS-ENG bilayer wavegui...

We describe the design of several novel, passive waveguide devices being developed for the high-power rf distribution system of the Next Linear Collider [1]. This system allows the combined power of several klystrons to be directed, by means of drive phase manipulation, to different accelerator feeds at different times during each pulse. The desire to reduce the amount of required low-loss, cir...

We analyze the existence and stability of nonlinear modes localized at phase-slip waveguide channels and their intersections in two-dimensional photonic lattices with rectangular symmetry. While in linear lattices only one localized mode of this type may exist under special conditions, nonlinearity supports a variety of localized modes including the modes which bifurcate from the symmetric stat...

The existing waveguide interface standards are generally found to be unsatisfactory above 110 GHz. An improved interface is proposed which is backward-compatible with the MIL-DTL-3922/67C standard and most of its higher-frequency variants. As there are currently no standard waveguide bands above 325 GHz, an extended set of bands is recommended for operation to 1100 GHz. Index Terms — Waveguides...

this paper presents a miniaturized open-ended rectangular waveguide antenna radiating below the cut-off frequency of the waveguide with a large bandwidth. Waveguide miniaturization is achieved by periodically loading the antenna with electromagnetic metamaterials consisting of infinity shaped resonators. The metamaterial cell is designed to have a high effective dielectric permittivity in the f...

Abstract—In this paper, a compact waveguide bandpass filter is proposed. The proposed structure consists of some inductive diaphragms in a rectangular waveguide and the regions between them have been filled fully by dielectrics. The relations between the physical and electrical parameters of the existed asymmetrical impedance invertors are obtained. The usefulness of the proposed structure and ...