Motorola Corporation

Ronald Dee Fuller

Hugh Robert Malone

Warren L Seely

Mark D Mosher

Robert D Fraser

Wade Norman Understiller

Rudy Michael Emrick

Craig L Fullerton

Richard M Dougherty

James F Landers

Thomas Andrew Roche

Benny W Lowe

Ken Brice-Heames

Robert W Zienkewicz

Ronald Frank Kielmeyer, Jr

An electromagnetic baffle arrangement includes a lid ( ) having a trough or air gap ( ) in the side walls of each cavity ( ) of lid ( ). Conductive strips ( ) are applied to a layer of printed circuit board ( ) and each of the legs ( ) of lid ( ). Optionally, to eliminate circulation of electromagnetic signals within air gap ( ) a grounded bolt ( ) may be inserted aperiodically.

Electromagnetic baffle for printed circuit boards

A moisture resistant conformal coating ( ) effectively protects high frequency circuits such as gallium arsenide MMICs from humidity and environmental contamination without the performance degradation inherent in conventionally applied conformal coatings. The conformal coating preferably comprises an organic polymer, such as silicone, applied to the MMIC die in a substantially uniform thickness of less than 0.002 inches, preferably of less than 0.0015 inches. This is accomplished by applying the organic polymer directly to the surface of the die ( ) in a mixture containing the solid organic polymer diluted with a low surface tension solvent, such as a volatile methyl siloxane.

High frequency gallium arsenide MMIC die coating method

An RF assembly ( ) operating at a predetermined wavelength of &lgr; and having a ground-plane interface ( ) between first and second components ( ) is presented. A bond wire ( ) couples the components ( ) along a bond-wire directrix ( ). The components ( ) have grounding members ( ) establishing substantially coplanar ground planes ( ). The grounding members ( ) are coupled together so as to create a semi-cylindrical slot ( ) having an opening ( ) substantially coincident with the ground planes ( ). The slot has an axis ( ) proximate the bond-wire directrix ( ), and a radius ( ) substantially equal to &lgr;/2. The slot axis ( ) and the bond-wire directrix ( ) are located within a plane ( ) substantially perpendicular to the ground planes ( ).

RF assembly with ground-plane slot between components and method therefor

An antenna system (,) capable of transmitting electromagnetic radiation using the technique of combining two quadrature signals for either right hand circular polarization or left hand circular polarization using a circularly polarized antenna (,), or alternately, either horizontal or vertical polarization using a linearly polarized antenna (,) while incorporating feedback for automatically correcting for amplitude and phase variations in the quadrature paths using a switch (,) which selects the sense of the polarization and electronic optimization of the transmit antenna (,). The antenna system includes a control circuit having a polarization switch (,) for receiving a transmission signal. The switch (,) generates first and second output signals which are substantially similar to the transmission signal, and determines whether to apply the transmission signal to one of a first or a second switch output. A coupler (,) receives the first and second switch outputs and generates first and second output signals having a predetermined phase difference. A variable detector (,) detects and adjusts a relative amplitude and phase of the respective first and second output signals. An error correction circuit (,) determines an adjustment to the variable phase detector to vary the phase and amplitude of the first and second output signals in accordance with the relative amplitude and phase of the respective first and second output signals.

Method for efficiently generating selectable antenna polarization

A method (60) for molding (67) a component (73) including a free floating insert (11). The method includes steps of providing an insert (11) including one or more weakened regions (23) coupled to a removable leader (20) and molding (67) a moldable compound (25) about the insert (11) and a portion of the removable leader (20). The method (60) further includes a step of pulling (69) on the removable leader (20) to fracture the weakened regions (23) and thereby detach the removable leader (20) from a molded component (73) including the insert (11) therein. The molding step (67) desirably includes a step of injection molding (67) a thermoplastic material (25) about the insert (11) and the portion of the removable leader (20).

Method of molding free-floating insert

A waveguide feed is fabricated by first creating a lead frame (10) from a piece of conductive material. The lead frame (10) is shaped by bending arms (22) and probe portions (18) on the lead frame (10) into a desired shape. The lead frame (10) is then placed in a mold and dielectric molding material is added around relevant portions of the lead frame (10). After the dielectric molding material has solidified, excess molding material and extraneous portions of the lead frame (10) are removed from the molded feed assembly. The assembly can then be connectorized and inserted into a waveguide.

Molded waveguide feed and method for manufacturing same

Microwave parallel coupled line filters with direct taps having improved rejection of undesired signals near the pass-band are disclosed. Improved rejection is achieved by controlling the transmission zeros created by the input and output direct taps. Performance is comparable to parallel coupled line filters having substantially more coupling sections. The method involves shifting the transmission zeros by changing the position of the direct taps along the resonator or changing the impedance of the open-circuited stub associated with each tap. Impedance transformers can be used to match back to the source and load impedances.

Coupled line filter with improved out-of-band rejection

An electrostatic RF absorbant circuit carrier assembly production method including the steps of forming a polymeric support structure having a base and surrounding walls which form an internal cavity from plastic, disposing a plurality of conductor paths within the cavity, forming a polymeric cover having wall members integrally fashioned into a surface thereof, for making contact with conductor paths within the cavity, depositing a layer of surface material on the cover and the cover wall members, said surface material comprising:

Method for making electrostatic RF absorbant circuit carrier assembly

An electrostatic RF absorbant circuit carrier assembly (200) is described as having a plastic support structure (100) which consists of an integrally fashioned base (180) and surrounding sidewalls (170) which together form an internal cavity (185). A plurality of conductor paths (125,165) are disposed within the cavity (185). The assembly (200) is completed by a polymeric cover (110) having a surface integrally fashioned to comprise wall members (145) for making contact with conductive paths (165) within the cavity (185). In order to facilitate RF isolation and electrostatic dissipation, the cover (110) is layered with a surface material comprising:

Electrostatic RF absorbant circuit carrier assembly and method for

Inductorless bias networks include a bias circuit having a bias return path which is coupled to and biases a variable impedance device in a relatively nonconductive state. Another bias circuit including a FET renders the variable impedance device relatively conductive in response to control signals so that one port is coupled to another port, for instance.

Broad band microwave biasing networks suitable for being provided in

A ring shaped dielectric resonator tuned by inserting a bolt from below the resonator into an opening of the resonator. The bolt causes the dielectric constant of the opening to change. The change in the dielectric constant changes the electric field which in turn changes the magnetic field of the resonator.

Growing community of inventors

Mesa, AZ, United States of America

Ronald Dee Fuller