Having Standing Wave Pattern Patents (Class 324/645)
  • Patent number: 12085535
    Abstract: Apparatus and method are provided wherein by measuring both the electrical permittivity and the electrical conductivity of the measured multiphase fluid, the resultant amplitude and phase angle of the induced complex voltage can be analysed. The phase angle data can be analysed to provide information on the electrically conductive phase, and that information can be employed to analyse the amplitude data, in particular to use the information on the electrically conductive phase to determine the contribution to the amplitude data by the electrically non-conductive phase. This analytical technique enables the electrical permittivity of the electrically non-conductive phase to be accurately determined. By determining the degree of contribution to the complex voltage measurement by both the permittivity and the conductivity, enhanced measurement accuracy of a multiphase fluid can be achieved.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: September 10, 2024
    Assignee: ENERCORP ENGINEERED SOLUTIONS, LLC
    Inventors: Lu Ma, Yessica Arellano
  • Patent number: 11646178
    Abstract: A controller of a plasma processing apparatus stores a frequency spectrum related to a first timing into a storage unit, controls a microwave generator to generate a microwave in correspondence to a setting frequency, setting power, and a setting bandwidth at a second timing, controls a demodulator to measure travelling wave power and reflected wave power of the microwave for each frequency, calculates the frequency spectrum related to the second timing on the basis of a measurement result from the demodulator, calculates a correction value for correcting a waveform of the travelling wave power for each frequency such that a difference for each frequency between the frequency spectrum related to the second timing and the frequency spectrum related to the first timing, stored in the storage unit, is small, and controls the microwave generator on the basis of the calculated correction value for each frequency.
    Type: Grant
    Filed: April 27, 2021
    Date of Patent: May 9, 2023
    Assignee: Tokyo Electron Limited
    Inventors: Yuji Onuma, Hideo Kato
  • Patent number: 11579060
    Abstract: Disclosed is a method for determining of fat content of milk having variable solids fractions and flowing with variable gas content in a pipeline. The method includes ascertaining a velocity of sound and an average density value for the milk based on eigenfrequencies of at least two bending oscillation wanted modes of measuring tubes of a densimeter arranged in the pipeline. The method further includes ascertaining a static pressure in the pipeline; a gas volume fraction based on the velocity of sound; the average density; the pressure; a density of the milk without gas content based on the average density and the gas volume fraction; and a permittivity of the milk based on a propagation velocity and/or an absorption of microwaves in the milk. The fat fraction is calculated based on the density of the milk without gas content and on the effective permittivity.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: February 14, 2023
    Assignee: Endress+Hauser Flowtec AG
    Inventors: Stefan Pflüger, Wolfgang Drahm, Hao Zhu
  • Patent number: 10897733
    Abstract: The present disclosure relates to a user equipment (200) for a wireless communication system. The user equipment comprises a transmitter (210) configured to generate a transmit signal (220), a transmitter feedback receiver (230) coupled to the transmitter and configured to measure a power of the transmit signal in a first mode of operation, and control circuitry (240) configured to select a second mode of operation of the transmitter feedback receiver, in which the transmitter feedback receiver (230) is configured to measure one or more neighboring inter-frequency or inter-RAT base stations.
    Type: Grant
    Filed: August 1, 2017
    Date of Patent: January 19, 2021
    Assignee: Apple Inc.
    Inventors: Zhibin Yu, Bernhard Sogl, Markus Dominik Mueck, Biljana Badic
  • Patent number: 9954749
    Abstract: A detection circuit is used to detect a connection state between a first signal port of an electronic device and a first external device. The detection circuit includes a signal generator, a switch module, a signal detector, and a processing unit. The signal generator generates a test signal. During a test process, the signal generator is electrically connected to the first signal port by the switch module, such that the test signal is sent to the first signal port to test the connection state of the first signal port. The signal detector produces a detection signal according to the connection state of the first signal port. The processing unit determines the state of connection between the first signal port and the first external device by comparing the voltage of the detection signal with a threshold value.
    Type: Grant
    Filed: March 17, 2015
    Date of Patent: April 24, 2018
    Assignee: GETAC TECHNOLOGY CORPORATION
    Inventor: Hung-Tu Chen
  • Patent number: 9363852
    Abstract: An apparatus and a method for heating a load using microwaves is disclosed. The apparatus includes a transmission line, configured to transmit microwaves from a microwave generator to a cavity. A sensing device configured to measure electromagnetic field strengths for providing information about the phase and the amplitude of a reflection coefficient that represents a ratio between the amount of microwaves reflected back towards the microwave generator and the amount of microwaves transmitted in the transmission line from the microwave generator. A control unit configured to detect whether the measured electromagnetic field strengths correspond to a reflection coefficient having a phase within a certain interval of phases and an amplitude within a certain interval of amplitudes. Additionally, certain intervals of phases and amplitudes correspond to an operating region of the microwave generator. The control unit controls feeding of microwaves to the cavity based on this detection.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: June 7, 2016
    Assignee: Whirlpool Corporation
    Inventors: Hakan Carlsson, Nordh Ulf
  • Patent number: 9155164
    Abstract: The invention relates to an HF system that comprises an HF device (5), particularly an HF lamp, as well an HF spark-plug or similar HF plasma application, and an HF signal-incoupling device (3) for operating said HF device (5). The HF system comprises an oscillator (7) for generating an HF signal to operate said HF device (5), and said system is characterised in that it comprises means (15) for generating a voltage signal (Uprop) that is proportional to the degree of adaptation of the HF device, on the basis of the HF signal generated by the oscillator (7) and a signal reflected by said HF device. Moreover, the system is characterised in that it comprises a device (27), preferably without a microprocessor, for generating a control signal (UA) for adapting the oscillator (7) output-frequency on the basis of the voltage signal (Uprop) which is proportional to the degree of adaptation of the HF device (5).
    Type: Grant
    Filed: November 22, 2012
    Date of Patent: October 6, 2015
    Inventors: Holger Heuermann, Arash Sadeghfam
  • Patent number: 8723531
    Abstract: An integrated RF circuit has an RF input port and an RF output port coupled to an external circuit element having known impedance such as an antenna. An RF circuit element is disposed between the RF input port and the RF output port and has a first input port and a first output port. The RF circuit element affects a signal received at the first input port and provides the affected signal to the first output port. The integrated RF circuit also has a VSWR detector circuit that measures a ratio of a characteristic of RF signals at the first input port and the first output port and that provides an indication of the ratio at a VSWR output port. The measured ratio of the characteristic is affected by an impedance of the coupling thereby providing an indication relating to the coupling.
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: May 13, 2014
    Assignee: SiGe Semiconductor, Inc.
    Inventor: Jose Harrison
  • Patent number: 8558556
    Abstract: A co-axial microwave bolometer architecture is disclosed that uses thick-film processes to construct very small thermistors on a substrate that is selected for low heat transfer. Thermal isolation is further enhanced by making the planar electrodes from a metal with lower heat transfer than typical electrical metals. Furthermore, a resistor with very strong temperature coefficient (thermistor), is arranged such that connecting metal paths are arranged axially, and as generally flat, thin, planar conductors. Additionally, the substrate of the thermistor is selected to have very low conductivity of heat, so the thermistor element itself is well isolated thermally from its surroundings.
    Type: Grant
    Filed: January 3, 2011
    Date of Patent: October 15, 2013
    Assignee: Tegam, Inc.
    Inventors: Jefferson D. Lexa, Andrew S. Brush, John D. Swank
  • Patent number: 8552739
    Abstract: In an electronic device and a method of correcting time-domain reflectometers, two channels of a time-domain reflectometer are connected to a corrector using cables, and the two channels are enabled to transmit pulses. Parameters Step Deskew and Channel Deskew of the two channels are zeroed. Resistance values of the two channels are measured simultaneously, and the value of the parameter Step Deskew of one of the two channels is adjusted according to the Resistance values of the two channels. Times of achieving the same resistance value of the two channels are measured after the cables and the connector have been disconnected, and the value of the parameter Channel Deskew of one of the two channels is adjusted according to the times of achieving the same resistance value. The adjusted values of the parameters Step Deskew and Channel Deskew are displayed through a display unit.
    Type: Grant
    Filed: March 4, 2011
    Date of Patent: October 8, 2013
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Hsien-Chuan Liang, Shen-Chun Li, Shou-Kuo Hsu
  • Patent number: 8035400
    Abstract: The enhanced detection of defects and features in bulk dielectric materials is disclosed. Microwave radiation partly reflected at interfaces where the dielectric constant changes (e.g., where there are defects or structures). A sinusoidal or quasi-sinusoidal wave results. Localization or imaging of features is enhanced by exploiting the variation in distance resolution in a sinusoidal or quasi-sinusoidal standing wave. At characteristic distances, the wave has a high slope, and the amplitude of the wave varies strongly with small changes in distance. By inspecting at these characteristic distances, the resolution is enhanced. By systematically varying the position of the transducer or specimen, detailed images may be formed of the internal structure of the specimen across a range of depths. Defects and structures may be detected at smaller sizes than has previously been possible. The resolution of the imaging may be substantially smaller than the wavelength of the interrogating radiation.
    Type: Grant
    Filed: July 21, 2010
    Date of Patent: October 11, 2011
    Inventor: Jack R. Little, Jr.
  • Publication number: 20100231236
    Abstract: An integrated RF circuit is disclosed having an RF input port and an RF output port. The RF output port is for being coupled with a known impedance to an external circuit element such as an antenna. At least an RF circuit element is disposed along a propagation path between the RF input port and the RF output port. The RF circuit element has a first input port and a first output port and is for affecting a signal received at the first input port and providing the affected signal to the first output port. The integrated RF circuit also has a VSWR detector circuit for measuring a ratio of a characteristic of RF signals at the first input port and a same characteristic of the RF signals at the first output port and for providing an indication of the ratio at a VSWR output port. The measured ratio of the characteristic is affected by an impedance of the coupling thereby providing an indication relating to the coupling.
    Type: Application
    Filed: March 1, 2010
    Publication date: September 16, 2010
    Applicant: SiGe Semiconductor Inc.
    Inventor: Jose Harrison
  • Patent number: 7778317
    Abstract: A method for detecting inductive elements in a communication line, including the processes of: inputting a detecting signal to an end of the communication line; sampling the time domain voltage vector of one end of the communication line; generating the amplitude-frequency characteristic curve of the differential input impedance of one end of the communication line according to the time domain voltage vector; determining the number of the inductive elements in the communication line according to the number of the apexes or zeros on the curve. The present invention also discloses a device for detecting inductive elements in a communication line. By the present invention, the automatic detections of the number of inductive elements such as load coils or phone splitters in the communication line are implemented with the exact detection and the high efficiency, thereby lowering the cost of detecting failures of communication line.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: August 17, 2010
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Zhaoguo Jin
  • Publication number: 20100001744
    Abstract: [Problem] To precisely measure a standing wave to be an indication for comprehending a guide wavelength ?g or the like in a waveguide. [Means for Solving] A distribution of temperatures is detected in a conductive member forming at least a part of pipe walls of a waveguide with respect to a longitudinal direction of a waveguide which propagates an electromagnetic wave, and a standing wave generated in the waveguide is measured based on the temperature distribution. The temperature distribution in the conductive member with respect to the longitudinal direction of the waveguide can be measured precisely with a plurality of temperature sensors disposed along the longitudinal direction of the waveguide, a temperature sensor which moves along the longitudinal direction of the waveguide, or an infrared camera.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 7, 2010
    Applicants: Tokyo Electron Limited, Tohoku University
    Inventors: Masaki Hirayama, Tadahiro Ohmi
  • Patent number: 7631543
    Abstract: A method for determining the composition and water salinity of a multi-component mixture of a gas and at least one liquid, including water, in a pipe (1), the method comprising the following steps: a. electromagnetic phase measurements are performed between two receiving antennas (4) located at different distances from a sending antenna (3), b. based on an empirically determined constant(s) and the above measurements, the effective and imaginary dielectric constants are determined, c. the mixture density is determined, d. the temperature and pressure are determined e. based on the knowledge of densities, effective dielectric constants and imaginary dielectric constants of the components of the fluid mixture and the results of the above steps a-d, the volume fractions of the gas and liquid or liquids of the fluid mixture and salinity of the water are calculated. An apparatus for performing the method is also disclosed.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: December 15, 2009
    Assignee: Multi Phase Meters AS
    Inventor: Arnstein Wee
  • Patent number: 7414424
    Abstract: Power measurement and control in transmission systems are affected by changes in load conditions. A method and system are provided for detecting and controlling power levels independent of such load conditions.
    Type: Grant
    Filed: November 7, 2006
    Date of Patent: August 19, 2008
    Assignee: Harris Stratex Networks Operating Corporation
    Inventors: Yen-Fang Chao, Cuong Nguyen, Roland Matian
  • Patent number: 7151382
    Abstract: A magnitude of radio frequency voltage and current, input into a load from a radio frequency power source, are measured at a single point along a transmission line. Phase difference between voltage and current is also measured. These measurements are used to compute VSWR and forward input power. The computed measurements may be compared against predetermined VSWR limits, and operation of the radio frequency power source can be adjusted to prevent damage to the detection apparatus or load.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: December 19, 2006
    Assignee: Rockwell Collins, Inc.
    Inventors: Timothy L. Kean, David L. Krett, Ted J. Hoffman, Edward J. Anthony
  • Patent number: 7076213
    Abstract: An apparatus and method for testing a voltage standing wave ratio (VSWR) in a wideband code division multiple access (W-CDMA) mobile communication system. Upon detecting a VSWR test request, a controller determines an oscillation frequency information and a power level information of a test signal for a VSWR test, and generates a test signal generation request including the determined oscillation frequency information and power level information. Upon detecting the test signal generation request, a test signal generator generates a test signal corresponding to the oscillation frequency information and power level information, and provides the generated test signal to an antenna. A VSWR detector receives the test signal and a reflected signal of the test signal from the antenna, and calculates a VSWR using the received test signal and reflected signal.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: July 11, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jin-Su Lee
  • Patent number: 7071700
    Abstract: The structural and termination characteristics of a telephone or other wiring circuit can be determined by generating a continuous stream of low-energy electrical signals, injecting these into the circuit under test, and analyzing the energy reflected at impedance changes in the frequency domain. Standing waves occurring in the circuit can be identified as a function of frequency and analyzed to locate the impedance discontinuities. An unambiguous numerical representation of the circuit can be generated and used to categorically determine if two circuits are indeed alike, or whether the structural and termination characteristics of a particular circuit has remained the same or changed over time. Waveforms are employed that are not sensed by circuits that carry digital telephone traffic, so that the invention is useful in characterizing and providing security protection for those type of circuits in situ.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: July 4, 2006
    Assignee: Wire Eye Co.
    Inventor: Timothy F. Gorka
  • Patent number: 6989676
    Abstract: A method and apparatus for detecting soot and/or water concentrations in diesel engine oil having a dielectric constant may include a device for measuring a change in the dielectric constant at a first frequency, a device for measuring a change in the dielectric constant at a second frequency and a processor configured to calculate at least one of a percentage of soot content and a percentage of water content as a function of the measured changes in the dielectric constant at the first and second frequencies. The first frequency may be within approximately the ultrasonic and sub-AM frequency bands and the second frequency may be within approximately the microwave frequency band.
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: January 24, 2006
    Assignee: Delphi Technologies, Inc.
    Inventor: Louis L. Nagy
  • Patent number: 6925616
    Abstract: A method for testing a core power distribution system for an integrated circuit chip which includes arranging a plurality of experiments for an integrated circuit chip, performing the plurality of experiments for the integrated circuit chip over a range of frequencies over a range of power distribution system impedances, generating a schmoo diagram for each of the plurality of experiments, and analyzing the schmoo diagrams to determine whether the core power distribution system functions is acceptable at a particular frequency.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: August 2, 2005
    Assignee: Sun Microsystems, Inc.
    Inventors: Leesa Noujeim, Bidyut K. Sen
  • Patent number: 6882162
    Abstract: A system for the wireless transmission of information and energy between a removable vehicle seat and the vehicle body, in which the vehicle seat is detected by measuring the inductance. In this connection, the period of an oscillating circuit is determined, in which the winding of the primary side, and thus the inductance, is connected. In this context, the frequency of the resonance voltage is determined as a function of time. In this context, the zero crossings of the resonance voltage is measured. Alternatively, the secondary side impedance is additionally measured on the primary side by a forced oscillation, namely by a voltage decay in a resonance circuit in which the winding is connected as inductance. A monitoring of the performance reliability of a firing pellet is thereby implemented.
    Type: Grant
    Filed: May 25, 2002
    Date of Patent: April 19, 2005
    Assignee: Robert Bosch GmbH
    Inventors: Juergen Schirmer, Harald Kazmierczak
  • Patent number: 6853181
    Abstract: A channel architecture for use in automatic test equipment is disclosed. The channel architecture comprises pattern generation circuitry and timing circuitry responsive to the pattern generation circuitry to generate timing signals. Formatting circuitry coupled to the output of the timing circuitry generates pulse waveforms for application to pin electronics circuitry. The pin electronics circuitry is responsive to the formatting circuitry for interfacing the automatic test equipment to a device-under-test. The pattern generation circuitry, the timing circuitry, the formatting circuitry and the pin electronics circuitry are formed on the same integrated circuit.
    Type: Grant
    Filed: December 31, 2003
    Date of Patent: February 8, 2005
    Assignee: Teradyne, Inc.
    Inventor: Edward Ostertag
  • Patent number: 6788072
    Abstract: A method and apparatus for detecting an accumulation of particles with a medium such as the soot content in diesel engine oil including generating a first waveform at a first frequency and a first voltage level to produce a standing wave having a voltage null point where at least a portion of the standing wave is passed within a portion of the oil. Generating a second waveform at a second frequency and a second voltage level to place a signal associated with a second voltage null point at a detection location for determining the signal's null point voltage level. The percentage soot content of the oil may be determined by taking the ratio of the difference between the first voltage and the second voltage over the null point voltage at the detection point. This ratio is indicative of the percentage soot content. The first and second waveforms may be produced by a variable frequency microwave source that is coupled with a coaxial cable have a probe affixed to its distal end for immersion in the oil.
    Type: Grant
    Filed: January 13, 2003
    Date of Patent: September 7, 2004
    Assignee: Delphi Technologies, Inc.
    Inventors: Louis L. Nagy, Warren Baxter Nicholson
  • Patent number: 6657440
    Abstract: A method for creating a full or partial transparency in a material comprising the steps of creating a first electromagnetic wave adjacent to the material, saturating the material with the first electromagnetic wave, creating a second electromagnetic wave having a frequency higher than the first electromagnetic wave, engaging the second electromagnetic wave with the material when the material is saturated for creating a transparency in the material with respect to the electromagnetic waves. An apparatus for creating a transparency in a material comprising a large coil, a small coil, a switch, a low noise amplifier (LNA), a receiver, a frequency generator, a pulsar, at least one or more capacitors and a power source.
    Type: Grant
    Filed: June 12, 1999
    Date of Patent: December 2, 2003
    Assignee: EM-Tech Sensors LLC
    Inventor: Bijan K. Amini
  • Patent number: 6411106
    Abstract: This invention provides a method and apparatus for the sensing of moisture using microwave technology. The apparatus provides a wave guide having a linear array of slots in its broadwall. A detector detects reflected energy of microwave signals over a frequency range once the material is positioned over the slots. A value indicative of the power spectral density of the reflected signals is computed and a value for the moisture content of the material determined from the value of power spectral density. The slots are at an angle with respect to the longitudinal axis of the wave guide and the angle can be varied according to the material being tested.
    Type: Grant
    Filed: October 5, 2000
    Date of Patent: June 25, 2002
    Assignee: Industrial Research Limited
    Inventors: Wayne S. Holmes, Stephen G. Riley, Richard B. Keam
  • Patent number: 6380748
    Abstract: An apparatus and method for diagnosing antennas using switches, wherein a system is configured in such a manner that a plurality of switches determine a data flow of a signal for test. Therefore, the antenna diagnosing apparatus can be so simplified in circuitry construction that it can be easy to manufacture at low cost. Further, the antenna diagnosing apparatus can accurately measure standing wave ratios of the antennas without being subject to any error, so as to accurately diagnose the performance of the antennas.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: April 30, 2002
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Min Soo Kang, Churl Hur, Seok Jun Hong, Yang Seok Song
  • Patent number: 6313644
    Abstract: An apparatus for measuring a voltage standing wave ratio of a base station. The apparatus comprises: a unit for measuring the voltage standing wave ratio of a transmitting terminal by coupling an input signal from the base station, and by comparing the difference of the coupled signal and a signal reflected from a transmitting antenna; and another unit for measuring the voltage standing wave ratio of a receiving terminal by comparing an input signal from a base-station test unit with the signal reflected from a receiving terminal.
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: November 6, 2001
    Assignee: LG Information & Communications, Ltd.
    Inventors: Young Min Kim, Bo Jong Kim, Dae Won Kim
  • Patent number: 6192318
    Abstract: A recording medium suitable for use in an impedance matching apparatus adapted to a waveguide transmitting a microwave to a load. The apparatus includes detecting diodes and a computer. The recording medium includes a program, which includes predetermined approximate expressions. The predetermined approximate expressions recorded in the program correspond to the detecting diodes. The program causes the computer to compute an approximation value of input power to the waveguide using the respective predetermined approximate expressions and output voltages of the detecting diodes.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: February 20, 2001
    Assignee: Fujitsu Limited
    Inventors: Toshiya Yogo, Atsushi Okuda, Masaaki Yano, Tomoyuki Mori
  • Patent number: 5982251
    Abstract: A tuner for radio frequency coaxial cable transmission lines is provided. It requires only one micrometer adjusting screw since the capacitor electrode that mates with the central conductor of the coaxial line is not only curved to give a large area in proximity to the central conductor but is rectangular and much longer than the diameter of the micrometer screw.
    Type: Grant
    Filed: March 14, 1998
    Date of Patent: November 9, 1999
    Assignee: Bruno O. Weinschel
    Inventors: Bruno O. Weinschel, David E. Young
  • Patent number: 5804976
    Abstract: A measurement device and a method for indicating the ratio of two or more substances having different dielectric constants which form a body of material is described. The measurement device comprises an oscillator (1), a transmission line (5) connected at one end to the oscillator (1) and a probe unit (7) connected to the other end of the transmission line (5). The oscillator (1) transmits an oscillating signal via the transmission line (5) to the probe unit (7), where the probe unit (7) contacts with the body of material. The difference in voltage amplitude between two points in the transmission line (5) is measured, and is indicative of the ratio of the two or more substances.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: September 8, 1998
    Assignee: Macaulay Land Use Research Institute of Craigiebuckler
    Inventor: Graham James Gaskin
  • Patent number: 5796322
    Abstract: In high frequency apparatus such as for example an rf resonant cavity or a waveguide, it is often necessary to include a slot to permit a probe or other member to be located in the high frequency region and be moveable along the slot. Sealing means arranged adjacent to the slot and around the probe permits movement of the probe whilst minimising the open aperture area of the slot, hence preventing or reducing leakage through it. In one embodiment of the invention, the sealing means comprises a metallic mesh and in another it includes an elastomer material which is loaded with metallic material and/or carries a metallic mesh.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: August 18, 1998
    Assignee: EEV Limited
    Inventors: Mark Bridges, Graham Michael Hood, Philip William Laurence Gandy
  • Patent number: 5659253
    Abstract: An RF detector circuit (28), which may be utilized in an output power control loop (10) for an RF transmitter, includes a bridge circuit (50) including a first arm (52) containing a first diode (D2) which rectifies the RF signal and a second arm (54) which contains a second diode (D3) series-coupled to the first diode (D2), and having an RF bypass capacitor (C4). The second diode (D3) serves as a temperature compensator for the first diode (D2). The outputs of the bridge circuit (50) are connected to the inputs of a differential amplifier circuit (32) which provides a signal for use in the power control loop (10). The detector input signal is derived from the sense output of a directional coupler (22). In a second embodiment the compensating diode (D13) has its cathode coupled to the cathode of the rectifying diode (D12), and the full voltage across the rectifying diode (D12) is applied to the differential amplifier circuit (32).
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: August 19, 1997
    Assignee: Lucent Technologies Inc.
    Inventor: Erik B. Busking
  • Patent number: 5621331
    Abstract: Methods for rapidly adjusting the impedance of a variable impedance apparatus to match the impedance of a source to the impedance of a load, where the load impedance is a nonlinear function of the power delivered to the load, are described. In addition, an automatic impedance matching apparatus for matching the impedance of a source to the impedance of a load and for maintaining a stable plasma are described. The apparatus includes a variable impedance apparatus, a plurality of electric field sensors, a photosensitive detector, a data processor, and a memory.
    Type: Grant
    Filed: July 10, 1995
    Date of Patent: April 15, 1997
    Assignee: Applied Science and Technology, Inc.
    Inventors: Donald K. Smith, Brian D. McVey, Richard A. Rameriz
  • Patent number: 5539322
    Abstract: The present invention relates to a method and related apparatus for the nondestructive determination of n layers of coating of a target having n layers of dielectric coating applied to an electrically conductive base material, comprising; a generator of electromagnetic waves in the microwave frequency range, including a microwave oscillator, a waveguide attached to the oscillator output and having an output aperture, a voltage detecting diode disposed within the waveguide, a flat layer of material adapted to be placed in a position abutting the target and disposed over the aperture of the waveguide and having a thickness t which, together with the waveguide, will provide a fixed distance between the diode and the target, and a display responsive to the output of the detecting diode for indicating the layer characteristics of the dielectric coating on the electrically conductive base material.
    Type: Grant
    Filed: September 20, 1994
    Date of Patent: July 23, 1996
    Assignee: Wave Metric, Inc.
    Inventors: Reza Zoughi, Stoyan I. Ganchev
  • Patent number: 5507010
    Abstract: An arrangement for measuring the condition of a receiver antenna at a base station, utilizing an antenna amplifier positioned in connection with an antenna apart from other base station equipments, e.g., at a mast. A measuring signal is generated in connection with the other base station equipments at a frequency outside the frequency band used for radio traffic and applied through an antenna line to the antenna amplifier, in which the measuring signal is converted to the actual measuring frequency within the frequency band intended for the radio traffic.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: April 9, 1996
    Assignee: Nokia Telecommunications OY
    Inventor: Jalo Ahonen
  • Patent number: 5498863
    Abstract: An optoelectronic detector includes multilayered semiconductor structures that are placed at particular positions in a standing wave pattern in order to measure the intensity of the light beams passing through said structures' layers. The detector is made sensitive to particular wavelengths by either changing the light beams intensity or varying the absorbance of the layers.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: March 12, 1996
    Assignee: AT&T Corp.
    Inventor: David A. B. Miller
  • Patent number: 5399977
    Abstract: In a microwave power source apparatus for a microwave oscillator for generating a microwave, a DC power source supplies a DC power for generating the microwave to the microwave oscillator. A measuring section of a voltage standing wave detector is mounted on a microwave transmission line connected between the microwave oscillator and a microwave load, and measures either one of an impedance seen looking toward the microwave load at a mounted point thereof and a reflection coefficient thereat by detecting a voltage standing wave of the microwave being generated by the microwave oscillator and propagating on the microwave transmission line.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: March 21, 1995
    Assignee: Daihen Corporation
    Inventors: Yuji Yoshizako, Michio Taniguchi, Yuji Ishida
  • Patent number: 5365391
    Abstract: A distributed-constant circuit type magnetic field detector which includes a magnetic member whose permeability varies with changes in a magnetic field applied thereto disposed at a point where a magnetic field is produced in a distributed-constant circuit excited with an electromagnetic wave and a detector for detecting a change in electromagnetic field distribution in the distributed-constant circuit produced by a variation in permeability of the magnetic member upon application thereto of a magnetic field to be detected.
    Type: Grant
    Filed: February 27, 1992
    Date of Patent: November 15, 1994
    Assignee: Sony Corporation
    Inventors: Yasunari Sugiyama, Kiyoshi Kagawa, Masatoshi Hayakawa, Hiroyuki Ohmori
  • Patent number: 5216372
    Abstract: The thickness of the layers of rubber covering the steel belts within a tire can be measured by transmitting a microwave signal toward the outer surface of the tire and measuring the phase shift of the signal reflected by the tire. In the preferred embodiment, a waveguide is used to direct the microwave signal toward the tire. A standing wave is created within the waveguide by interference between the transmitted microwave signal and the microwave signal reflected from the tire. A series of crystal detectors mounted along the length of the waveguide measure the standing wave. A processor calculates the phase of the reflection coefficient, and determines the thickness of the rubber layer as a predetermined function of the phase. By proper selection of the microwave frequency and the spacing between the waveguide and the tire, the rubber layer thickness can be uniquely determined as a function of phase for any range of rubber thicknesses likely to be encountered in a tire.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: June 1, 1993
    Assignee: Colorado State University Research Foundation
    Inventors: Reza Zoughi, Sasan Bakhtiari
  • Patent number: 5103181
    Abstract: Radio frequency bridge techniques are used to parameterize the complex dielectric properties of solids, liquids, gasses and mixtures thereof. This parameterization is performed in an electrically isolated, physically open structure which allows continuous or batch monitoring of the materials and their mixtures. A method and apparatus are provided for measuring the composition of mutlicomponent process streams flowing in pipes or ducts. The method uses the pipe in which the mixture flows as a waveguide in which propagating radio frequency electromagnetic energy is induced through dielectric loaded apertures. The dielectric measurement is performed in an electrically isolated, flow through test section which induces constructive or destructive interference patterns at characteristics frequencies. The characteristic frequency determines the dielectric constant of the mixture. The dielectric properties are used in turn to determine mixture composition.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: April 7, 1992
    Assignee: Den norske oljeselskap a. s.
    Inventors: Scott G. Gaisford, John P. Watjen, Bjorn G. Bjornsen
  • Patent number: 5079507
    Abstract: There are disclosed an automatic microwave impedance adjusting apparatus for a microwave load connected to a microwave oscillator through a microwave transmission line, and an automatic microwave impedance adjusting method therefor. In the apparatus and method, there is measured either an impedance seen looking toward a microwave load at a predetermined reference point of a microwave transmission line connected between a microwave oscillator and the microwave load or a reflection coefficient thereat by detecting a voltage standing wave of a microwave propagating on the microwave transmission line. Thereafter, a controller controls variable impedance means mounted on the microwave load side of the reference point on the microwave transmission line responsive to the value measured at the first step, so as to adjust the impedance seen looking toward the microwave load to a predteremined value.
    Type: Grant
    Filed: January 29, 1990
    Date of Patent: January 7, 1992
    Assignee: Daihen Corporation
    Inventors: Yuji Ishida, Michio Taniguchi
  • Patent number: 5069070
    Abstract: Especially precise and reliable measurements and evaluations are obtained by measuring one or more propagation parameters of electromagnetic waves in a wave guide or resonator at least partially filled with fuel and evaluated in an evaluating circuit as the measure for the alcohol content and/or the calorific value. According to one embodiment, the travel time or the travel time difference of an electromagnetic wave between two or more points in a wave guide filled with fuel is determined and is evaluated through computer or circuit technology as the measure for the alcohol content and/or the calorific value.
    Type: Grant
    Filed: December 6, 1989
    Date of Patent: December 3, 1991
    Assignee: FEV Motorentechnik GmbH KG
    Inventor: Gunter Schmitz
  • Patent number: 5039949
    Abstract: A method of testing the reflectivity of RF absorber materials utilizes an elongated chamber lined with RF absorber material and having a source antenna at one end, with the other end terminating in either a "short circuit", or a piece of RF absorber material which is to be tested. A probe antenna is moved along the axis of the chamber and the standing wave created by the source antenna and the reflection from the other end is recorded, first with the short circuit condition, and then with the test sample in place, and the results are compared to yield a figure for the reflectivity of the test sample.
    Type: Grant
    Filed: June 1, 1987
    Date of Patent: August 13, 1991
    Inventors: Leland H. Hemming, Gabriel A. Sanchez
  • Patent number: 4996491
    Abstract: The linear position of an elongated element (1) is measured using a transmission medium (2). The transmission medium comprises an emitter (3) of microwaves and a receiver (4) of microwaves and has at its one end the elongated element (1) and at its other end an electrical short-circuit (23). An asymmetrical sawtooth standing wave with substantially linear flanks is generated by reflection of the microwaves on the short-circuit (23) and on the elongated element (1). The position of the elongated element is determined by measuring the amplitude of the longer flank of the standing wave with the receiver. The method may be used in difficult circumstances and is suitable to measure mechanical vibrations of high-frequency.
    Type: Grant
    Filed: June 7, 1989
    Date of Patent: February 26, 1991
    Assignee: N.V. Bekaert S.A.
    Inventor: John Vandorpe