The Boeing Company

Other

Hughes Aircraft Company

Hughes Electronics Corporation

Dreedco, Inc.

Richard L Bennett

Rolf Kich

James M Barker

Keith N Loi

Frederick A Young

Paul J Tatomir

James D Thompson

Louis W Hendrick

Thierry W Swinson

John D Marshall

David M Kershner

Kenneth L Cole

David Kershner

Eugene C Hunley, Jr

Eddie W Derryberry

Charles D Wachs

David A Patton

A microwave waveguide filter includes a main-line cavity structure with a group of at least two rectangular main-line cavities arrayed along a main propagation path and including a first main-line cavity and a second main-line cavity. Each main-line cavity includes a sidewall, and each pair of adjacent main-line cavities has a common transverse wall transverse to the main propagation path and a main-line aperture in the common transverse wall. A rectangular first feedback cavity is in microwave communication with each of the first main-line cavity and the second main-line cavity through the respective sidewall of the first main-line cavity and the second main-line cavity. There is a first-cavity feedback aperture between the first feedback cavity and the first main-line cavity, and a second-cavity feedback aperture between the first feedback cavity and the second main-line cavity. There may be additional feedback cavities as well.

Microwave waveguide filter having rectangular cavities, and method for its fabrication

H-plane offset transitions in a switchable waveguide

An apparatus and method for switching waveguides between a junction waveguide and a bypass waveguide among a plurality of housing ports. The apparatus comprises a housing having a first, second and third housing port and a waveguide rotor, having a first and second rotary position. The waveguide rotor includes a junction waveguide, having a first, second and third junction port, for combining the first, second and third housing ports in the first rotary position and a bypass waveguide, having a first and second bypass port, for connecting the first and second housing ports in the second rotary position. The junction and bypass waveguides are alternately selectable by rotating the waveguide rotor to the first and second rotary positions. The method comprises rotating a waveguide rotor including a junction waveguide having a first, second and third junction port and a bypass waveguide having a first and second bypass port, to a first rotary position in a housing including a first, second and third housing port, whereby the first, second and third junction ports connect the first, second and third housing ports and rotating the waveguide rotor to a second position a bypass waveguide, whereby the first and second bypass ports connect the first and second housing ports.

E-plane offset transitions in a switchable waveguide

A waveguide switch matrix is disclosed. The switch matrix includes a number of input waveguides that may be selectably connected to a number of output waveguides. A switch apparatus is provided at the intersection of each input waveguide and each output waveguide. The switch apparatus includes probes inserted into both the input waveguide and the output waveguide. The probes are connected through a switch arrangement. When a particular input waveguide is to be coupled to a particular output waveguide, the switch arrangement between the probes of the waveguides is closed to provide a signal path for the electromagnetic energy.

Waveguide switch matrix using junctions matched in only one state

A coaxial 'M' switch having three coaxial input connectors (A, B, C) spaced evenly from each other, and three coaxial output connectors (1, 2, 3) identically arranged. In a cylindrical barrel embodiment (10) the input and output connectors are located at opposite ends of a cylindrical configuration. In one planar embodiment (30), the input and output connectors alternate with each other and define a hexagonal configuration (40). In another planar embodiment, the input connectors (A, B, C) define an inner triangular configuration (70) that is surrounded by the output connectors (1, 2, 3) defining an outer triangular configuration. In each embodiment, reeds are actuated in predetermined configurations to define three switch positions.

Coaxial 'M' switch

A bandpass filter having 4-degrees of freedom includes a plurality of resonant cavities having respective Qs where at least one of the Qs is different. A plurality of main couplings couple successive resonant cavities to establish a main signal path that provides a first degree of freedom for controlling the shape of the filter's frequency response over its passband. A plurality of bridge couplings couple pairs of the resonant cavities so that the cavities are connected in a canonical circuit topology. The bridge couplings provide second and third degrees of freedom for controlling the sharpness of the frequency response 's transition between its passband and stopband and controlling the linearity of its phase, respectively. The cavities' non-uniform Qs provide a fourth degree of freedom for controlling the amplitude of the filter's frequency response in the passband so that the amplitude is within a predetermined tolerance of a desired passband shape.

Non-uniform Q self amplitude equalized bandpass filter

A high performance bandpass filter is produced by adding one or more 'simultaneous couplings' to a conventional resonant cavity filter. A 'simultaneous coupling' is created when a filter's input or output signal, normally coupled to a filter's first or last cavity respectively, is coupled to one or more other cavities. Each simultaneous coupling causes a finite-frequency insertion loss pole to be created, which produces a quasi-elliptic frequency response on its side of the passband. These poles may be placed on the left and/or right sides of the passband, so that both symmetric and asymmetric quasi-elliptic frequency responses are realizable. A diplexer constructed from two such bandpass filters has the extremely sharp selectivity provided by two asymmetric bandpass filters, thus providing a high degree of receive/transmit isolation.

Simultaneous coupling bandpass filter and method

A plural cavity structure (10), suitable for use as a microwave filter (34, 34A, 34B) , has plural cavities (24, 26, 28, 30) disposed within a cylindrical aluminum housing (12) and having a central planar transverse wall (18) including an iris (38) for coupling of electromagnetic power between two successive ones of the cavities (28, 26). The transverse walls are bowed, and peripheral regions of the walls are clamped by metallic rings (66, 68, 70, 72) differing in their coefficients of thermal expansion. Thus, the rings (68, 70) of the inboard transverse walls (16, 20) are formed of titanium having a relatively high coefficient of thermal expansion, while the rings (66, 72) of the outboard transverse walls (14, 22) are formed of INVAR having a relatively low coefficient of thermal expansion. As a result of the differing coefficients of thermal expansion, the outer transverse walls experience greater deformation than do the inner transverse walls with changes in environmental temperature resulting in a net decrease in axial length of both inboard and outboard cavities upon an increase in environmental temperature.

Tandem cavity thermal compensation

A bi-directional snap-action register mechanism for an odometer-type mechanical register display. The mechanism includes at least one register display wheel and a bi-directional cam mounted coaxially along a common shaft with the register display wheel. The bi-directional cam engages a helical groove formed along the shaft to allow lateral displacement of the bi-directional cam in a direction parallel to a rotational axis of the shaft. A pin is biased by a spring into contact with the bi-directional cam. Rotation of the shaft causes the bi-directional cam to be moved with respect to the pin. The cam abruptly rotates through a predetermined angular distance when the point of contact of the biased pin with the cam moved from a smooth portion to a step transition portion of the cam. The abrupt rotation of the cam is communicated to the register display wheel to cause a new display position to be moved into view.

Bi-directional snap-action register display mechanism

A flashlight holder includes a C-shaped clamp that holds a flashlight by friction. The clamp is attached by an angled arm to a tripod that supports the arm in a fixed position of choice. Magnet assemblies in the legs of the tripod are mounted so as to swivel, allowing the flashlight holder to be secured by magnetic force to a ferromagnetic surface. The flashlight holder is preferably made of low-density polypropylene, which is both inexpensive to buy and easy to mold in molds that require little or no relief. The angled arm makes it easy to set a flashlight at any orientation with respect to an iron or steel surface to provide light to work on car and truck engines and the like.

Growing community of inventors

Torrance, CA, United States of America

Richard L Bennett