There is disclosed a directional multi-band antenna comprising a substrate structure, a plurality of RF units arranged at the substrate structure to provide an RF phased array, the RF phased array having an angular scan range, an array of optical units arranged at the substrate structure and interspersed amongst the RF units, an array of optical lensing devices supported over the substrate structure, the array of optical lensing devices being substantially RF transmissive and being arranged to correspond with the arrangement of the optical units, such that each optical unit may communicate light signals with an associated optical lensing device so as to communicate light signals along an optical axis within the angular scan range of the RF phased array

Directional multiband antenna

The aim of the invention, is to develop a method of the type in question, for identification of gases and a corresponding device, which has a simple construction permitting an immediate and concurrent detection of the chemical compounds under examination and hence for identification of the material-specific mobility and at the same time the change in said mobility as a function of electrical field strength. Said aim is achieved, wherein each ionised molecule has a drift speed through the resultant electrical field, which is partly increased or reduced, the resulting electrical field being a DC field, with a superimposed asymmetrical alternating field. Said method and corresponding devices for detection and identification of gases are used for recognition and detection of chemical compounds, in particular of explosive and/or toxic materials or material compounds for detection in extremely low concentrations.

Method and device for detection and identification of gases

A method of manufacturing a semiconductor optical element, includes successively stacking a first semiconductor layer of a first conductivity type, an active layer, and a second semiconductor layer of a second conductivity type; applying a resist to the second semiconductor layer and patterning the resist into stripes by photolithography; forming recesses in the second semiconductor layer and a waveguide ridge adjacent to the recesses by dry-etching the second semiconductor layer only partially through the second semiconductor layer, using the resist as a mask; forming an insulating film on the waveguide ridge and in the recesses while leaving the resist; removing the insulating film from the resist so that the resist is exposed while the insulating film in the recess is left; removing the resist exposed; and forming an electrode on the waveguide ridge after removing the resist.

Method of manufacturing semiconductor optical element

A radio-frequency-device test range (the Refractive Compact Range) includes a physical space having a source zone for placing an antenna or array of antennas, and a test zone for placing a sensor or other device to be tested. A lens and an apodizer are placed in the physical space between the source zone and the test zone. The lens serves to collimate radiated energy emanating from the antenna toward the test zone. The lens may have a surface treatment, such as an anti-reflective coating or a surface pattern, on one or both surfaces. The apodizer functions to keep energy from diffracting off the edge of the lens and getting into the field of view (the test zone). The sensor or other device to be tested may be placed on a moveable mount to allow it to be moved, to simulate relative movement of the device and a radio frequency source, such as radiated by an antenna.

Refractive compact range

The quality factor of microwave resonators miniaturised by virtue of periodic loading is assessed. Five X-band resonators in E-plane technology with different miniaturisation factors have been designed to resonate at approximately the same frequency. The loaded quality factor is extracted from the fractional bandwidth and subsequently employed to estimate the unloaded quality factor. The study reveals that the unloaded quality factor drops approximately linearly with the miniaturisation. Subsequently design guidelines for E-plane filters with periodically loaded resonators are provided by means of an example involving a fifth-order filter. Full-wave simulated and experimental results are presented to validate the study.

Quality factor of E-plane periodically loaded waveguide resonators and filter applications

A reflective Fresnel lens for shaping an incident wave for efficiently delivering the incident wave to an array of receivers, having a wavelength within a predetermined range. The Fresnel lens comprises a ground plate and a plurality of reflective elements formed at various levels of the ground plate. The predetermined range includes millimeter wavelength range, sub-millimeter wavelength range or microwave wavelength range.

Reflective fresnel lens for sub-millimeter wave power distribution

A ridge waveguide filter having a slow-wave structure. The ridge waveguide has an elongate hollow tube formed of a conductive sidewall. At least a first part of the conductive sidewall periodically is recessed along an elongate direction of the hollow tube, such that a plurality of ridges is formed to project in the hollow tube. The sidewall is fabricated from metallic materials. The hollow tube includes a rectangular hollow tube or a circular hollow tube, for example. The ridges are equally spaced from and parallel with each other. Each of the ridges has a bottom surface parallel with a second part of the conductive sidewall. The second part of the conductive sidewall is opposite to the first part of the conductive sidewall.

Slow-wave structure for ridge waveguide

A method of fabricating a ridge waveguide filter having a slow-wave structure. The ridge waveguide is formed of a conductive sidewall-from metallic materials and may be in the form of a hollow tube, such as a rectangular hollow tube or a circular hollow tube, for example. The method comprises the steps of: forming a conductive body portion of an elongate hollow tube, wherein the body portion has an open top a bottom wall, two opposing side walls and an open top; providing a substrate having a top surface onto which a plurality of photoresist layers are formed; etching the top surface of the substrate to form a plurality of trenches in the substrate; plating the etched substrate surface with a layer of conductive material; and attaching the etched substrate to the conductive body portion to cover the open top of the conductive body portion.

Method for making a slow-wave ridge waveguide structure

One embodiment of the present invention includes a waveguide. The waveguide comprises an elongated member having a conductive bottom surface and a hollow channel. The hollow channel is defined by a first conductive sidewall, a second conductive sidewall, and a conductive inner surface. The waveguide also comprises a plurality of conductive ridge portions projecting from the conductive inner surface and extending between the first conductive sidewall and the second conductive sidewall. The conductive ridge portions can partition the hollow channel into a plurality of hollow recesses. The waveguide further comprises a plurality of switches associated with each of at least one of the plurality of conductive ridge portions. At least one of the plurality of switches associated with a respective one of the plurality of conductive ridge portions can be activated to couple the respective one of the plurality of conductive ridge portions to the conductive bottom surface.

Kent E. Peterson

Papers

Reflective fresnel lens for sub-millimeter wave power distribution

Slow-wave structure for ridge waveguide

Method for making a slow-wave ridge waveguide structure

Programmable Tunable Filter Waveguide