Presented in this paper is a conceptual design by computer simulation of monopulse reflector antenna with dual-circularly polarized sum patterns and linearly azimuth elevation difference patterns, which can be called semi-dual antenna. The proposed consists five-element feed prime-focus parabolic reflector. novelty the consisting square waveguide channel radiator rectangular radiators. separati...

First observation of generation in the backward wave oscillator with a ”grid” diffraction grating and lasing of the volume FEL with a ”grid” volume resonator that is formed by a perodic set of metallic threads inside a rectangular waveguide is considered.

This paper presents statistical signal processing approaches for clutter reduction in Stepped-Frequency Ground Penetrating Radar (SF-GPR) data. In particular, we suggest clutter/signal separation techniques based on principal and independent component analysis (PCA/ICA). The approaches are successfully evaluated and compared on real SF-GPR time-series. Field-test data are acquired using a monos...

A quadra-ridged waveguide transformer (QRWT) is proposed for full-band matching between a standard and half-height waveguide, which meets the need compact components multiple sections of irregular transmission lines better in wider operation bands. Unlike conventional circuits with monotonically changing impedances, QRWTs form abrupt cross-section changes line steps. The initial configuration Q...

In the millimeter-wave bands, the series-fed array antenna is facing a problem of large transmission loss and narrow bandwidth by using a high permittivity and large-loss tangent material. In this report, an air-layer is inserted in a LTCC waveguide of εr=6.6 and tanδ=0.013 to reduce the transmission loss. The reduction of the equivalent dielectric constant by the air insertion structure enhanc...

Fabrication process of multimode 1 x 2 optical rectangular planar power splitter suitable for low-cost short distance optical network is presented. The splitters were designed by beam propagation method for standard input/output plastic optical fibre. Materials used for the splitter were: UV acrylate photopolymer polymer or epoxy resin for optical core waveguide layers and Y-groove substrate fo...

A design procedure is developed for slotted-waveguide antennas with probe-fed slots. Radiation into a gyrotropic, plane-stratified medium is considered, nonzero waveguide wall thickness is assumed, and noncosinusoidal slot fields and arbitrary slot length up to about one free-space wavelength are allowed. External mutual coupling is taken into account by matching the tangential fields at the an...

We describe a waveguide to thin-film microstrip transition for highperformance submillimetre wave and teraherz applications. The proposed constant-radius probe couples thin-film microstrip line, to fullheight rectangular waveguide with better than 99% efficiency (VSWR ≤ 1.20) and 45% fractional bandwidth. Extensive HFSS simulations, backed by scale-model measurements, are presented in the paper...

We study the wakefield in a plasma filled rectangular waveguide based on a differential equation derived in terms of the wake potential , when the pulse duration matches with inverse of the plasma frequency fp 1 . This equation is solved using fourth-order Runge-Kutta method for the Gaussian-like profile of the microwave pulse. The effects of microwave frequency f , waveguide width b and microw...

Waveguide-fed plastic horn antennas have been demonstrated for W-band applications using a versatile and cost-effective micro hot embossing process. The three-dimensional (3D) polymer structure with internally coated conductor is composed of a pyramidal horn, an E-plane waveguide bend, two resonant cavities for impedance matching and a connecting rectangular waveguide. Measurement results show ...