Abstract: A slot line band pass filter formed on a dielectric substrate. In one embodiment, the filter includes input and output positive and negative signal conductors and resonators for coupling a signal of a desired frequency between input and output conductors. Various resonator arrangements are disclosed. In another embodiment, a filter having a resonator connected to and disposed between positive and negative conductors is taught. In yet other embodiments, filters having loop resonators are disclosed.

Abstract: A flared trough waveguide antenna capable of being used at high microwave and millimeter wave frequencies is disclosed herein. The antenna includes a conductive trough having first and second ends, a bottom surface, and first and second opposing side surfaces electrically coupled to the bottom surface. A conductive fin is electrically coupled to the bottom surface between the first and second opposing side surfaces. The bottom surface includes a first planar portion between the conductive fin and the first side surface, and a second planar portion between the conductive fin and the second side surface. The conductive trough may be induced to radiate electromagnetic energy by introducing an offset between the first and second planar portions with respect to the plane of the conductive fin. The antenna further includes first and second flared surfaces, respectively coupled to the first and second side surfaces, for directing electromagnetic energy radiated by the flared trough waveguide antenna.

Abstract: Mixers assemblies including mixer cells, baluns, quadrature mixers and image reject mixers, etc. The mixer cell may contain CPW strip RF input and slot line strip LO input. LO signal return is provided through a flip-chip mounted to a mixer contact area and the CPW RF input is preferably coupled to the contact area through a distributed or flip-chip mounted capacitor. The use of two mixer cells in novel embodiments of quadrature and image reject mixers is disclosed. CPW to slot line power dividing baluns for use within and without such mixers are also disclosed.

Abstract: An active device, such as a field effect transistor ("FET"), converts microwave signals between a slot transmission line ("slotline") and a coplanar waveguide ("CPW") In slotline-to-CPW conversion using one or more FETs, a gate connection is made to one or both of the slotline conductors. A drain connection is made to the center conductor on the CPW. Two FET source terminals are connected respectively to each CPW ground strip and may be coupled to a slotline conductor. The active device can be reconnected so as to reverse the input and output, providing for conversion of signals from CPW to slotline. Conversion between balanced-signal slotline and CPW further includes passive or active phase shift of one signal path.

Abstract: An abdominal incision suturing apparatus includes a guide element that is inserted and maintained in an abdominal incision by a guide handle. The guide element has a passage for receiving slidably the shaft of a reverse needle. The shaft can be moved axially and rotationally with respect to the guide element by a shaft handle. The reverse needle has a needle at the distal end of the shaft, with a pointed end and an eye for receiving a suture. The guide element defines a sheath for receiving the pointed end of the needle. The guide element and the reverse needle together present a substantially airtight surface for maintaining the pneumoperitoneum pressure in a cannula site incision. Further, the guide element includes markings on its surface, for the user to monitor the depth of insertion via a laparoscope. The shaft handle has a specially shaped groove, and the guide element has an internal pin that protrudes into the groove.

Abstract: A varactor comprising a substrate of semiconductor material on which is grown both an electrostatic barrier having a first layer of material doped with donor impurities and a second layer of material doped with acceptor impurities and a depletable layer. In other embodiments of the present invention varactors are provided that include a plurality of barrier and depletable layer pairs grown in a serial arrangement.

Abstract: A coplanar band pass filter having a centerline formed of at least first and second serially arranged conducting segments which are separated by a gap. The centered segments are flanked by a resonator for coupling return current from the first and second segments. Conducting members that may include conductive strips or conductive planes are respectively provided on opposing sides of the resonator and centerline. Band pass elements may be provided in the conductive strips or planes to reduce or eliminate spurious pass band frequencies.

Abstract: An amplifier including an amplifying transistor flip-mounted on a coplanar waveguide pattern. Elements of stability and/or matching circuits are provided at least in part under the flip-mounted transistor to facilitate compact design and to improve component performance. A serial resistor-shunt inductor pair is provided with the resistor coupled proximate the transistor input and/or output and preferably configured within the CPW center conductor to provided more consistent component values. Embodiments of the present invention include a two-stage amplifier having a transmission segment formed between the two stages which serves to rotate the output impedance of the first stage toward a low noise match with the second stage and to rotate the input impedance of the second stage toward a high gain match with the first stage. The transmission segment may include a capacitive element for providing series capacitance and DC blocking. Adjustable impedance matching means are also taught.

Abstract: A seating support cushion system has a seat cushion with an H-shaped inflatable cell, with the sides of the "H" extending parallel to a cushion axis that corresponds to the longitudinal axis of a person sitting on the cushion, and therefore parallel to the thighs. The crossbar cell is midway in the cushion, forward of the location of the position of the ischial tuberosities of a person supported on the cushion. A pair of inner cells fill in the voids of the "H" shape, with one cell in the rear of the cushion positioned for supporting the ischial tuberosities. This rear cell also preferably has a recess for receiving the coccyx without significant pressure, and a secondary crossbar portion adjacent to the crossbar cell. A back cushion has two sets of alternatingly inflated, laterally extending cells forming a spinal recess and contoured to conform to the shape of a person's back.

Abstract: A process of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide.

Abstract: A seating support cushion system has a seat cushion with an H-shaped inflatable cell, with the sides of the "H" extending parallel to a cushion axis that corresponds to the longitudinal axis of a person sitting on the cushion, and therefore parallel to the thighs. The crossbar cell is midway in the cushion, forward of the location of the position of the ischial tuberosities of a person supported on the cushion. A pair of inner cells fill in the voids of the "H" shape, with one cell in the rear of the cushion positioned for supporting the ischial tuberosities. This rear cell also preferably has a recess for receiving the coccyx without significant pressure, and a secondary crossbar portion adjacent to the crossbar cell. A back cushion has two sets of alternatingly inflated, laterally extending cells forming a spinal recess and contoured to conform to the shape of a person's back.

Abstract: A radio-frequency power amplifier includes a multiple-FET chip that is flip mounted on a connection region of a substrate. An input impedance-matching network is also mounted on the substrate. The network includes a coplanar waveguide having an elongate waveguide signal conductor for each gate terminal on the FET chip with a distal end spaced from the connection region and a proximal end in the connection region. The distal ends are connected to a single base input conductor. The proximal ends are flip mounted to respective ones of gate terminals of the FET chip. A capacitor couples each of the input signal conductor distal ends to an adjacent ground conductor. The signal conductors and capacitors provide a selected impedance at a selected frequency. The capacitors may be on a separate chip flip mounted to the waveguide signal and ground conductors, and may be formed as coplanar waveguides with open-ended signal conductors.

Abstract: A seating support cushion system has a seat cushion with an H-shaped inflatable cell, with the sides of the "H" extending parallel to a cushion axis that corresponds to the longitudinal axis of a person sitting on the cushion, and therefore parallel to the thighs. The crossbar cell is midway in the cushion, forward of the location of the position of the ischial tuberosities of a person supported on the cushion. A pair of inner cells fill in the voids of the "H" shape, with one cell in the rear of the cushion positioned for supporting the ischial tuberosities. This rear cell also preferably has a recess for receiving the coccyx without significant pressure, and a secondary crossbar portion adjacent to the crossbar cell. A back cushion has two sets of alternatingly inflated laterally extending cells forming a spinal recess and contoured to conform to the shape of a persons back.

Abstract: A means of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide.

Abstract: A generally cylindrical or partially cylindrical body is intimately received in an irrigation pipe and has an outer surface in physical contact with an inner surface of the pipe. A flow-limiting labyrinth is formed by the outer surface of the body in combination with the pipe inner surface. A valve chamber is formed in the body and has four pairs of inlets and outlets forming an inlet retention valve and three labyrinth bypass valves. The first inlet is in fluid communication with the pipe interior and the first outlet is in fluid communication with the labyrinth inlet end. The inlet retention valve includes a first valve seat that surrounds the first inlet. Each bypass valve is connected between a respective section of the labyrinth and an external pipe outlet.

Abstract: A driven element is disposed on an antenna axis for transmission of electromagnetic energy in a transmission direction along the antenna axis. First and second parasitic arrays are disposed on opposite sides of the antenna axis in the transmission direction from the driven element. At least a portion of the antenna axis adjacent to the parasitic arrays is without parasitic elements. Each parasitic array has a plurality of parallel parasitic elements or directors spaced apart along a respective array line that includes a proximal portion adjacent to the driven element that extends in a general direction that is at an acute angle to the transmission direction. The first and second parasitic arrays are sufficiently close to the antenna axis to produce a radiation pattern that has a lobe with greatest magnitude in the transmission direction.

Abstract: A means of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted to a circuit motherboard having large passive elements. A push-pull amplifier is presented as an example in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. The electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of striplines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide. In particular, a conversion of a split coplanar slotline to dual coplanar waveguides provides signal transmission to a pair of transistors flip-mounted onto the coplanar waveguides.

Abstract: An active device, such as a field effect transistor ("FET") or MMIC, converts microwave signals between a microstrip transmission line ("microstrip") and a coplanar wave guide ("CPW"). In microstrip-to-CPW conversion using a simple FET, a gate connection is made to the microstrip signal conductor. A drain connection is made to the center conductor on the CPW. Two FET source terminals are connected respectively to each CPW ground strip. The ground strips are electrically coupled to the microstrip ground plane with a minimum length connection so the inductance common to the FET input and output is minimized. The FET can be reconnected so as to reverse the input and output, providing for conversion of signals from CPW to microstrip. Conversion from microstrip to an intermediate CPW and back to microstrip provides for mounting an intermediate circuit, such as an amplifier or other MMIC, directly on the CPW.