Patents Assigned to Radio Frequency System, Inc.
  • Publication number: 20130222081
    Abstract: Various exemplary embodiments relate to an antenna feed configured to receive a signal having a wavelength. They antenna feed may include a cylindrical body and four pin groups. Each pin group may include two pins in close proximity extending across the center of the cylindrical body. One of the two pins may be rotated approximately 22.5° from the angle of the other pin. Each pin group may be spaced approximately one quarter of a wavelength away from each other, and may be rotated approximately 22.5° from the angle of the previous pin group.
    Type: Application
    Filed: February 28, 2012
    Publication date: August 29, 2013
    Applicant: Radio Frequency Systems, Inc.
    Inventor: James W. Nelson
  • Patent number: 7956707
    Abstract: An apparatus for coupling a combline resonator and a ceramic resonator, including one or more of the following: a housing; a combline resonator in the housing; a ceramic resonator in the housing, the ceramic resonator having a stem portion and a mushroom portion; a ridge extending between the combline resonator and the ceramic resonator, the ridge passing between the mushroom portion of the ceramic resonator and the housing, wherein a coupling is obtained between an electrical field of the combline resonator and an electrical field of the ceramic resonator.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: June 7, 2011
    Assignee: Radio Frequency Systems, Inc.
    Inventor: Bill Engst
  • Patent number: 7948334
    Abstract: An apparatus includes a shell member having an interior width, where the shell includes a closed end and an open end, and a nut that includes a plurality of laterally extending resilient leg. The legs define an outer width of the nut, and when the legs are in a relaxed state the outer width of the nut is greater than the interior width of the shell. The nut is adapted for at least partially entering the open end of the shell member, such that the legs are placed in a tensioned state in which the legs define the outer width to be smaller than or equal to the interior width of the shell. The apparatus also includes a base plate adapted for receiving the shell member and securing the shell member to the base plate with the closed end of the shell facing away from the base plate through cooperation with the nut when the nut is at least partially within the shell member.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: May 24, 2011
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Adam J. Jones, Samuel Parent
  • Patent number: 7915978
    Abstract: Various exemplary embodiments include a technique for tuning a filter to have two stop bands. This technique may involve combination of signals from a plurality of high-band notch resonators and low-band notch resonators. Loop wires may couple both high-band and low-band notch resonators to a central conductor, thereby enabling the central conductor to transmit a signal having dual stop bands.
    Type: Grant
    Filed: January 29, 2009
    Date of Patent: March 29, 2011
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Yunchi Zhang, Michael Joseph Adkins
  • Publication number: 20110032854
    Abstract: An arrangement of hybrid couplers, selectively removing RF amplifiers from a receiving path from an antenna back to a receiver in response to an event, the event switching impedances of switchable impedances connecting to ports of the hybrid couplers, between a matching impedance and mismatching impedance. The matching and mismatching impedances change coupling characteristics of the hybrid couplers between a normal coupling and a bypass coupling. In the normal coupling the hybrid couplers provide port-to-port coupling placing the RF amplifiers within the receiving path and, in the bypass coupling, the hybrid couplers provide port-to-port coupling bypassing the RF amplifiers. Optionally, transmitted signal power is detected to identify transmit and receiving intervals.
    Type: Application
    Filed: August 5, 2009
    Publication date: February 10, 2011
    Applicant: Radio Frequency Systems, Inc.
    Inventors: Paul Carney, Jing Wang
  • Patent number: 7777598
    Abstract: A combline filter has a ceramic resonator disposed inside at least one cavity wall. Because the resonator is implemented as a hollow rod, a tuning element may be inserted into an opening on the top of the rod to tune its frequency. A mounting element, inserted into an opening on the bottom of the rod secures its position inside a cavity resonator. Instead of soldering the resonator to the filter's walls, the resonator is supported above a bottom or side wall of the cavity resonator.
    Type: Grant
    Filed: April 14, 2008
    Date of Patent: August 17, 2010
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Hamid Reza Salehi, Teppo M. Lukkarila
  • Publication number: 20100188174
    Abstract: Various exemplary embodiments include a technique for tuning a filter to have two stop bands. This technique may involve combination of signals from a plurality of high-band notch resonators and low-band notch resonators. Loop wires may couple both high-band and low-band notch resonators to a central conductor, thereby enabling the central conductor to transmit a signal having dual stop bands.
    Type: Application
    Filed: January 29, 2009
    Publication date: July 29, 2010
    Applicant: Radio Frequency Systems, Inc.
    Inventors: Yunchi Zhang, Michael Joseph Adkins
  • Patent number: 7755456
    Abstract: A triple-mode filter is disclosed, the triple-mode filter including a cavity for confining electromagnetic waves and a metallic block acting as a resonator within that cavity. The metallic block does not contact the conductive walls of the cavity, but is instead suspended by a support element. Triple-mode resonators may be combined to produce bandpass filters having three or more poles. In other configurations, triple-mode cavity metallic resonators may be coupled to triple-mode cavity ceramic resonators or to combline resonators to achieve various filtering functions and performances suitable for different applications.
    Type: Grant
    Filed: April 14, 2008
    Date of Patent: July 13, 2010
    Assignee: Radio Frequency Systems, Inc
    Inventor: Hamid Reza Salehi
  • Publication number: 20100127801
    Abstract: An embedded resonator sharpens the frequency characteristics of a coaxial low pass filter. The resonator introduces finite transmission zeros to the response of the low pass filter, thereby suppressing spurious modes occurring just above the operating frequency. Two parameters are used to tune the operation of the embedded resonator. The length of an insert into the filter's transmission line substantially controls the resonant frequency, and the gap width substantially controls the coupling of the embedded resonator to the low pass filter.
    Type: Application
    Filed: November 21, 2008
    Publication date: May 27, 2010
    Applicant: Radio Frequency Systems, Inc.
    Inventor: Michael Joseph Adkins
  • Patent number: 7327210
    Abstract: A microwave filter and method for remotely tuning a microwave filter from one sub-band to another sub-band using metallic rings to adjust the capacitance or inductance of the resonator. In adjusting the capacitance, a plurality of metallic rings are disposed in the upper section or end of the resonator. Each ring has an RF switch that connects or disconnects each ring to ground, thereby varying the capacitance of the resonator. In adjusting the inductance, a plurality of metallic rings are disposed perpendicular to the magnetic field of the resonator. Each ring has an RF switch disposed within the electrical path of the ring that opens or closes the electrical path of each ring. By opening and closing each ring, the magnetic field of the resonator is altered, thereby varying the inductance of the resonator.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: February 5, 2008
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Bill Blair, Jeff Blair, Bill Engst, Robert Laemmle, Greg Lamont, Weili Wang, William Wilber
  • Patent number: 7113149
    Abstract: An antenna including a metallic reflector; a radiating element disposed on the reflector; a metallic power divider disposed on the reflector; a coaxial cable interconnecting the power divider to the radiating element; and a clamp for clamping the coaxial cable to the reflector or the power divider, wherein the clamp is unitary with the reflector or the power divider. There may be multiple clamps for clamping the cable to both the reflector and the power divider as necessary to secure the cable in place. Also, there may be a plurality of coaxial cables. The clamp includes a metallic plate having an opening for receiving the coaxial cable. The opening is preferably stamped in the metallic plate. The opening is preferably substantially U-shaped and the coaxial cable is frictionally retained in the opening by a press fit. More specifically, the clamp includes opposing leg portions and a base portion which define the opening.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: September 26, 2006
    Assignee: Radio Frequency Systems, Inc.
    Inventors: David Cornec, Damien LeGrand
  • Patent number: 7099696
    Abstract: An angle diversity antenna system utilizes a first antenna, a second antenna, and a panel combiner coupled to the first and second antenna. In a transmit mode, the first and second antenna are coupled to a transmit sum channel of the panel combiner. In a receive mode, either the sum channel or a difference channel of the panel combiner is chosen as the active channel. By monitoring the sum channel and difference channel, the antenna system according to the present invention is able to select the channel which supplies the greatest signal strength.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: August 29, 2006
    Assignee: Radio Frequency Systems, Inc.
    Inventor: Frederic Lecuyer
  • Patent number: 7006054
    Abstract: A novel locking mechanism for mounting a radio to an antenna. The mounting face of a radio is secured to the mounting portion of an antenna. The mounting portion of the radio has a locking ring on which a plurality of radio locking tabs are located at equally spaced positions. The ring can be fixed to the radio, or in another embodiment, is still secured to the radio but can rotate independently. The mounting portion of the antenna has a corresponding number of equidistantly spaced tension springs, which have a plurality of spring fingers. To mount the radio to the antenna, the radio locking ring with radio locking tabs is twisted so that each antenna tension spring is deflected by a corresponding radio locking tab. The engagement of the radio locking ring to the antenna spring fingers secures the radio to the antenna. The deflection force also produces a friction force.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: February 28, 2006
    Assignee: Radio Frequency System, Inc.
    Inventors: Dennis Rosenfeld, Robert Hathaway, Adrian T. Utrilla
  • Patent number: 6993286
    Abstract: The dual band bi-directional amplifier has only one amplifier chain having an uplink amplifier and a downlink amplifier, but can nonetheless amplify signals from two frequency bands in both an uplink and a downlink direction between two antennas. This is possible by using duplexers and circulators to separate signals to and from each antenna into the two bands. In particular, for each frequency band handled by the circuit, the dual band bi-directional amplifier has a duplexer set for separating the signals from one of the bands into the uplink and downlink direction. In the case of a dual band amplifier, there are two sets of duplexers, one for each band. By using duplexers and circulators to differentiate signals in different bands travelling in different directions, there is no need for additional amplifier chains, which increase the manufacturing costs.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: January 31, 2006
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Liping Zhen, David L. Wills
  • Patent number: 6956068
    Abstract: The present invention is directed to a novel foamed polymer material for use as a dielectric in electric transmission lines. The foam dielectric of the present invention is obtained from extrusion of a polymer alloy and a supercritical fluid, especially carbon dioxide. Specifically, the foam polymer dielectric is made by: (1) feeding a polymer alloy into an extruder and heating the polymer alloy, (2) feeding a supercritical fluid into the extruder, (3) mixing the polymer alloy and the supercritical fluid, (4) exiting the polymer alloy and the supercritical fluid from the extruder, and (5) passing the polymer alloy and the supercritical fluid through a crosshead. The foam dielectric of the present invention may be used in coaxial transmission lines. In this embodiment, an inner conductor is surrounded by the foam dielectric, which is further surrounded by a second conductor. Stripline and microstripline transmission lines may also be manufactured using the disclosed foam dielectric.
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: October 18, 2005
    Assignee: Radio Frequency Systems, Inc.
    Inventors: Daniel E. Bufanda, Karl Audenaerde
  • Patent number: 6954122
    Abstract: A hybrid filter assembly is provided having a first ceramic triple-mode mono-block resonator, a second ceramic triple-mode mono-block resonator and at least one metallic resonator coupled to at least one of the first and second mono-block resonators. Each triple-mode mono-block resonator supports three resonant modes and each metallic resonator supports an additional mode, thereby providing a hybrid filter assembly of reduced size having more than six poles.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: October 11, 2005
    Assignee: Radio Frequency Systems, Inc.
    Inventors: William Wilber, Weili Wang
  • Patent number: 6926555
    Abstract: A tuned RF coaxial connector for mating a coaxial transmission line includes a cylindrical outer conductor, a coupling mechanism for mating the coaxial transmission line to the substantially cylindrical outer conductor, and an inner conductor extending coaxially within cylindrical outer conductor. One end of the cylindrical outer conductor interfits with the coaxial transmission line and another end of the cylindrical outer conductor interfits with an electrical device. The connector has an open circuit inner stub where the inner conductor of the transmission line couples to the inner conductor of the connector, or an open circuit outer stub where the outer conductor of the transmission line couples to the outer body of the connector, or both. Without the need for precise fitting of the conductors of the coaxial transmission line and the connector, the invention facilitates field installation of cables and connectors while reducing implementation cost.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: August 9, 2005
    Assignee: Radio Frequency Systems, Inc.
    Inventor: James W Nelson
  • Patent number: 6882242
    Abstract: A frequency selective low loss transmission system for communicating a signal using a coaxial cable of one impedance to a device of different impedance. A connector with a matching transformer is integral to the connector which terminates with a standard interface. The invention also includes a coupling mechanism to couple the coaxial cable with the connector. The invention can also include series open stub conductors for capacitive coupling to the conductors of the coaxial cable. In addition to low losses over a broad frequency range, the connector facilitates connector installation due to the series open stub conductor while reducing cost and complexity of both coaxial cable and connector.
    Type: Grant
    Filed: June 19, 2003
    Date of Patent: April 19, 2005
    Assignee: Radio Frequency Systems, Inc.
    Inventor: James W Nelson
  • Patent number: 6853271
    Abstract: The present invention incorporates triple-mode, mono-block resonators that are smaller and less costly. The size reduction has two sources. First, the triple-mode mono-block resonator has three resonators in one block. This provides a 3-fold reduction in size compared to filters currently used which disclose one resonator per block. Secondly, the resonators are not air-filled coaxial resonators as in the standard combline construction, but are dielectric-filled blocks. The coupling between modes is accomplished by the corner cuts. One oriented along the Y axis and one oriented along the Z axis. In addition, a third corner cut along the X axis can be used. Corner cuts are used to couple a mode oriented in one direction to a mode oriented in a second mutually orthogonal direction. Each coupling represents one pole in the filter's response. Therefore, the triple-mode mono-block discussed above represents the equivalent of three poles or three electrical resonators.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: February 8, 2005
    Assignee: Radio Frequency Systems, Inc.
    Inventors: William D. Wilber, Chi Wang, Weili Wang
  • Patent number: 6836198
    Abstract: A cavity filter which provides for fine tuning of the bandwidth of the filter. The filter provides for both capacitive cross-coupling and inductive coupling between physically adjacent but electrically non-adjacent resonators in the filter. The isolation of the filter can be fine tuned by adjusting the inductive coupling between these resonators, which has the effect of attenuating the cross-coupling effect between these resonators.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: December 28, 2004
    Assignee: Radio Frequency Systems, Inc.
    Inventor: Bill Engst