RF and microwave radiation directing or controlling components are provided that may be monolithic, that may be formed from a plurality of electrodeposition operations and/or from a plurality of deposited layers of material, that may include switches, inductors, antennae, transmission lines, filters, and/or other active or passive components. Components may include non-radiation-entry and non-radiation-exit channels that are useful in separating sacrificial materials from structural materials. Preferred formation processes use electrochemical fabrication techniques (e.g. including selective depositions, bulk depositions, etching operations and planarization operations) and post-deposition processes (e.g. selective etching operations and/or back filling operations).

Miniature RF and microwave components and methods for fabricating such components

For suppression of high-frequency spurious signals (noise) present on an electrical transmission line, the line incorporates at least one section comprising a distributed low-pass filter. This section is constructed so that its wave impedance (Z 1 ) has a different value than the wave impedance (Z 0 ) of the neighboring line sections. This filter line section additionally provides considerable dielectric losses and/or skin effect losses. At both ends of the filter line section, at which the wave impedance changes, multiple reflections arise that attenuate the high-frequency spurious signals (noise). The dielectric or skin effect losses produce strong attenuation of the undesired resonances that arise from the reflections, as well as further attenuation of spurious signals in the highest frequency region.

Line with distributed low-pass filter section wherein spurious signals are attenuated

The present invention is a passband-type waveguide filter in which a periodic distortion is employed which has a sinusoidal, or alternately configured, distortion, which changes phase at a point along the periodic distortion. The passband filter comprises essentially any waveguide, designed as a waveguide, with a periodic distortion added to at least one of the sides of the waveguide. The waveguide can be a rectangular cross section metallic microwave type, cylindrical, elliptical, or microstrip. The waveguide may be optical, a SAW type waveguide or any waveguide of the prior art. In a preferred embodiment a waveguide structure supports propagation of a wave along the waveguide, the waveguide structure containing a boundary and the waveguide structure containing a filter portion having a portion of said boundary with a sinusoidal distortion following: f(z)=1+A sin (k.sub.w z) for 0<=z<=L/2 f(z)=1-A sin (k.sub.w z) for L/2<=z<=L where f(z) is a distance perpendicular to the boundary, z is a distance along the wall in the direction of wave propagation, A is a dimensionless amplitude <<1, kw is the boundary wave number chosen to satisfy the Bragg condition k w =2k m , and L is the length of the filter portion waveguide.

Narrowband waveguide filter

An RF device disposed in a vacuum-like environment including two RF electrodes capable of supporting multipacting in at least a RF high voltage region thereof has disposed therebetween a solid dielectric material having a given dielectric constant and a given dielectric strength to eliminate multipacting.

Method and arrangement to eliminate multipacting in RF devices

An embedded resonator sharpens the frequency characteristics of a coaxial low pass filter. The resonator introduces finite transmission zeros to the response of the low pass filter, thereby suppressing spurious modes occurring just above the operating frequency. Two parameters are used to tune the operation of the embedded resonator. The length of an insert into the filter's transmission line substantially controls the resonant frequency, and the gap width substantially controls the coupling of the embedded resonator to the low pass filter.

Low pass filter with embedded resonator

A low pass microwave filter comprised of a two conductor transmission line including at least two cascaded tapered sections wherein one of the conductors in each filter section has a tapered surface, preferably linear, and having an electrical length substantially equal to one half the wavelength of the center frequency of operation. Geometrically and performance-wise the subject filter is unsymmetrical with respect to its input and output ports. The filter does not exhibit the usual rapid transition between the pass band and stop band which is a general characteristic of conventional low pass microwave filters utilizing reflective harmonic structures.

Helmuth M Kaunzinger

Papers

Low pass microwave filter