Patent application number | Description | Published |
20090219111 | PHASE SHIFTER WITH FLEXIBLE CONTROL VOLTAGE - The invention provides a phase shifter with flexible control voltage that is useful with all RF systems that phase shift a RF signal. The phase shifter according to the present invention may comprise transistors used as switching elements. In one aspect, the phase shifter provides the option of controlling a phase shifter with either a positive or a negative voltage control signal. For example, the dc ground of the transistors included in the phase shifter may be floated, either fixed or adjusted. The RF grounding of the transistors may be achieved by in-band resonant capacitors. Thus, the control voltage provided to the transistors is flexible in that it may be connected to a positive or negative control voltage, or it may be connected to ground, or it may swing from a positive control voltage to a negative control voltage or vice versa. | 09-03-2009 |
20090219112 | PHASE SHIFTER WITH FLEXIBLE CONTROL VOLTAGE - The invention provides a phase shifter with flexible control voltage that is useful with all RF systems that phase shift a RF signal. The phase shifter according to the present invention may comprise transistors used as switching elements. In one aspect, the phase shifter provides the option of controlling a phase shifter with either a positive or a negative voltage control signal. For example, the dc ground of the transistors included in the phase shifter may be floated, either fixed or adjusted. The RF grounding of the transistors may be achieved by in-band resonant capacitors. Thus, the control voltage provided to the transistors is flexible in that it may be connected to a positive or negative control voltage, or it may be connected to ground, or it may swing from a positive control voltage to a negative control voltage or vice versa. | 09-03-2009 |
Patent application number | Description | Published |
20090115512 | DISTRIBUTED DOHERTY AMPLIFIERS - Doherty and distributed amplifier (DA) designs are combined to achieve, wideband amplifiers with high efficiency dynamic range. A modified Doherty amplifier includes a wideband phase shifter providing first and second outputs, a main amplifier coupled to the first output, an auxiliary amplifier coupled to the second output, and a wideband combining network combining the outputs in phase. A multi-stage DA has a main output and a termination port, and a phase delay module and transforming network allowing power at the termination port to be combined in phase with power at the main output. In one combination, one or more stages of the DA may comprise a Doherty amplifier. In another combination, a modified series-type Doherty amplifying system is achieved by cascading main and auxiliary DAs. In any combination, Doherty topology may include a bias control module. | 05-07-2009 |
20100117766 | CAPACITIVELY LOADED SPURLINE FILTER - In an exemplary embodiment, a spurline filter comprises a capacitive element connected to a spur and either a through-line of the spurline filter or ground. In another embodiment, multiple capacitive elements are connected to the spur. In an exemplary embodiment, the capacitively loaded spurline filter provides a band rejection frequency response similar to the band rejection frequency response of a similar spurline filter that does not comprise at least one capacitive element but the capacitively loaded spurline filter has half the layout area or less. In an exemplary embodiment, the spurline filter comprises capacitive elements, where the capacitive elements are configured to reduce the resonant frequency of the filter. | 05-13-2010 |
20110248784 | MULTI-CHIP DOHERTY AMPLIFIER WITH INTEGRATED POWER DETECTION - In accordance with an exemplary embodiment of the present invention, a Doherty amplifier is provided for applications in radio frequency, microwave, and other electronic systems. An exemplary Doherty amplifier comprises a first MMIC having a first power detector, and a second MMIC having a second power detector. The first MMIC and the second MMIC are structurally identical. Furthermore, the first MMIC is configured as a carrier amplifier and the second MMIC is configured as a peaking amplifier. In the exemplary embodiment, an amplifier control bias of the carrier amplifier is a function of the power detected by the first power detector and an amplifier control bias of the peaking amplifier is a function of the power detected by the second power detector. The ability to assemble a Doherty amplifier using a single MMIC product results in a simple and less expensive manufacturing process. | 10-13-2011 |
20110250861 | HIGHLY INTEGRATED, HIGH FREQUENCY, HIGH POWER OPERATION MMIC - A system and method for high frequency, high power operation communication systems is provided. More particularly, a system and method for a single system-on-chip system monolithic microwave integrated circuit that provides both high-frequency performance at a low cost is provided. | 10-13-2011 |
20110285467 | Distributed Doherty Amplifiers - Doherty and distributed amplifier (DA) designs are combined to achieve, wideband amplifiers with high efficiency dynamic range. A modified Doherty amplifier includes a wideband phase shifter providing first and second outputs, a main amplifier coupled to the first output, an auxiliary amplifier coupled to the second output, and a wideband combining network combining the outputs in phase. A multi-stage DA has a main output and a termination port, and a phase delay module and transforming network allowing power at the termination port to be combined in phase with power at the main output. In one combination, one or more stages of the DA may comprise a Doherty amplifier. In another combination, a modified series-type Doherty amplifying system is achieved by cascading main and auxiliary DAs. In any combination, Doherty topology may include a bias control module. | 11-24-2011 |
20120194275 | Distributed Doherty Amplifiers - Doherty and distributed amplifier (DA) designs are combined to achieve, wideband amplifiers with high efficiency dynamic range. A modified Doherty amplifier includes a wideband phase shifter providing first and second outputs, a main amplifier coupled to the first output, an auxiliary amplifier coupled to the second output, and a wideband combining network combining the outputs in phase. A multi-stage DA has a main output and a termination port, and a phase delay module and transforming network allowing power at the termination port to be combined in phase with power at the main output. In one combination, one or more stages of the DA may comprise a Doherty amplifier. In another combination, a modified series-type Doherty amplifying system is achieved by cascading main and auxiliary DAs. In any combination, Doherty topology may include a bias control module. | 08-02-2012 |
20130021111 | Transistor Switches With Single-Polarity Control Voltage - Contrary to phase shifters which require complimentary polarity control voltages, a phase shifter may be driven with a single polarity control voltage. The phase shifter comprises an input node in communication with both a high pass network and a low pass network which are both in communication with an output node, where the phase shifter further comprises a first single pole double throw switch and a second single pole double throw switch configured to selectively pass an RF signal from the input node to the output node by way of one of said high pass network and said low pass network. Furthermore, the first and second single pole double throw switches are configured to select between the high pass network and the low pass network based on a single control signal having a voltage greater than or less than a reference voltage. | 01-24-2013 |
Patent application number | Description | Published |
20100007093 | Seal Assembly and Rotary Machine Containing Such Seal - A seal assembly which, among other applications, may be used for sealing fluid leakage between a steam or combustion (gas) turbine rotor and a turbine stator body. The seal assembly includes elements having a plurality of spaced leaf seal members with slots therebetween. Each leaf seal member is angled out-of-plane between a fixed end and a free end thereof, and the free ends slidably engage the rotatable component. A support may be provided supporting the free end such that it contacts a distal end of the support in an operative state and is out of contact with the distal end in an inoperative state. Seal members may include two different materials having different coefficients of thermal expansion. In one embodiment at least one damping leaf can be provided on a low pressure side of a leaf seal member. | 01-14-2010 |
20110135454 | LEAF SEAL ASSEMBLY INCLUDING POLYMER MEMBER AND ROTARY MACHINE CONTAINING SUCH SEAL ASSEMBLY - A seal assembly which, among other applications, may be used for sealing fluid leakage between low temperature multistage compressors and pumps, steam turbine rotors and turbine stator bodies. In accordance with the invention a seal assembly is provided that comprises a leaf seal including a plurality of staggered leaf seal members; and a polymer member disposed on a high pressure side of the leaf seal, wherein the polymer member is in compliant contact with the leaf seal. | 06-09-2011 |
20110304101 | FILM RIDING PRESSURE ACTUATED LEAF SEAL ASSEMBLY - In accordance with embodiments of this invention, a pressure actuated leaf seal assembly is provided that includes film riding, hydrodynamic/hydrostatic runners under seal member leaf ends. Leaf seal assemblies according to embodiments of this invention maintain the runner away from a rotating body until adequate rotating speed is present to generate lift required to allow the runner to float on a thin film of operating fluid on the rotating body, so that the runner does not rub the rotating body. In addition, runners are attached, or added, to leaf seal members such that the runners move in a radial direction, while remaining parallel to the rotating body. In one embodiment, a runner can comprise a separate structure coupled to a leaf seal member, and in another embodiment, a runner can comprise a wear-resistant pad on a distal end of a leaf seal member. | 12-15-2011 |