Patents Assigned to Allen Telecom
  • Patent number: 5515064
    Abstract: A window mounted antenna system having a foot or exterior support member attached to an antenna radiator or whip and typically mounted on the outside of a window or dielectric member comprised of a plastic decorative housing, a conductive foot portion which acts as the coupling capacitor and is inserted into the cover and conductively connected to the radiating member or whip, and a fastener for attaching the whip to the foot or base portion. The conductive foot includes attachment fingers insertable into the housing and retained in place upon insertion therein, and one or more flanges for receiving a fastener passed through the end of the antenna. A coupling assembly disposed on the other side of the window includes a formed or stamped conductive element which incorporates the various conductive components which make up the coupling assembly.
    Type: Grant
    Filed: June 25, 1993
    Date of Patent: May 7, 1996
    Assignee: Allen Telecom Group, Inc.
    Inventors: James A. Bacnik, James Hadzoglou
  • Patent number: 5495216
    Abstract: A dual-mode dielectric-resonator-loaded cavity filter comprises a generally cylindrical cavity, at least two longitudinally-spaced dielectric resonator elements coaxially aligned within the cavity, and at least one coupling obstacle disposed between the resonators and extending a distance from the cavity wall. The coupling obstacles are preferably conductive and are electrically connected to the cavity wall. However, the obstacles may be constructed of a dielectric material in some applications. Each obstacle may be aligned with one of the reference planes corresponding to a resonant mode of the resonators to effectively control or reduce the coupling between the parallel resonant modes of adjacent resonators. The reduction in coupling between resonant modes of adjacent resonators allows large coupling differentials to be produced, allowing a filter designer to implement a wide variety of high-performance filters without expensive irises.
    Type: Grant
    Filed: April 14, 1994
    Date of Patent: February 27, 1996
    Assignee: Allen Telecom Group, Inc.
    Inventor: Douglas Jachowski
  • Patent number: 5446729
    Abstract: An improved multiplexer comprises a housing, a transmission line transformer section within the housing extending in a first direction, and at least two interdigital transmission line filters adjacently disposed within the housing along the first direction. The transformer section has a first end electrically coupled to an antenna circuit connector, and a second end electrically coupled to the housing (i.e. grounded). Each filter includes several resonating elements. At least one resonating element of each filter is located in proximity with a portion of the transformer such that electrical coupling between the filter and the transformer is established. The length of each coupling portion of the transformer is approximately one-quarter electrical wavelength at the center frequency of the associated filter. The dimensions of the filter cavities are preferably selected to be as small as possible without unacceptably degrading the filter insertion loss.
    Type: Grant
    Filed: November 1, 1993
    Date of Patent: August 29, 1995
    Assignee: Allen Telecom Group, Inc.
    Inventor: Douglas R. Jachowski
  • Patent number: 5440281
    Abstract: A multichannel combiner includes a plurality of input ports for connection to associated transmitters, narrow bandpass filters associated with each port, and an output port for connection to an antenna system. The output impedance of the filters is selected to be substantially lower than that used in conventional combiners, such that undesired reactance produced in the combiner over its operating range is much reduced. The combiner further includes an impedance transformer to match the low output impedance of the filters to the design impedance of the antenna system.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: August 8, 1995
    Assignee: Allen Telecom Group, Inc.
    Inventors: Chia-Sam Wey, John M. Stronks, Erik W. Lilieholm
  • Patent number: 5428325
    Abstract: An RF filter having a housing defining a cavity with plural elongated resonators and plural resonator decouplers adjacent each of plural pairs of the resonators in the housing. The decouplers are grounded adjacent each of their ends only to the housing to provide an enhanced resonator decoupling effect. The filter may instead comprise a dielectric block with resonator holes and resonator decoupler holes each appropriately metalized with the decoupler holes being grounded at each end at external metalized block surfaces.
    Type: Grant
    Filed: December 10, 1993
    Date of Patent: June 27, 1995
    Assignee: Allen Telecom Group, Inc.
    Inventors: Douglas R. Jachowski, David P. Halley, Chia-Sam Wey
  • Patent number: 5410284
    Abstract: A poly-band filter includes a folded metal housing which defines an interior region partitioned by a divider. First and second pluralities of resonators are provided in the housing. Alternately increasing and decreasing degrees of coupling are provided between adjacent resonators in the housing. Slot coupling is provided between first and second non-adjacent resonators displaced from input/output connectors for the filter.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: April 25, 1995
    Assignee: Allen Telecom Group, Inc.
    Inventor: Douglas R. Jachowski
  • Patent number: 5402135
    Abstract: A mobile communication antenna adjustably mounted to a base at desired angular orientations. A decorative cover snap locks to the base to cover the antenna base structure. The cover includes a small opening through which a portion of an articulating arm extends to provide a wide range of angle adjustments of the antenna within the opening in the cover. The articulating arm provides an offset between the antenna axis and the axis of pivotal movement.
    Type: Grant
    Filed: February 28, 1992
    Date of Patent: March 28, 1995
    Assignee: Allen Telecom Group, Inc.
    Inventors: Allen G. DeMarre, Clarence D. Zierhut
  • Patent number: 5343214
    Abstract: A mobile antenna system for use at frequencies in and above the 800 MHz band having a collinear radiator mounted on one surface of a dielectric such as the window of a vehicle. A coupling system is affixed to a second surface of the dielectric. The coupling system includes a counterpoise for coupling RF energy between the radiator and a transmission line connected to a suitable transceiver. Decoupling members connected to the counterpoise minimize coupling of radio frequency energy to defogger wires on the window.
    Type: Grant
    Filed: July 24, 1992
    Date of Patent: August 30, 1994
    Assignee: The Allen Telecom Group, Inc.
    Inventor: James Hadzoglou
  • Patent number: 5307075
    Abstract: A monolithically loaded microstrip antenna is provided for a communications function, such as a cellular telephone base station. The antenna includes a ground plane and a group of stacked, planar elements. A director element having a rectangular configuration together with monolithic load tabs is connected to a feed line and spaced above the ground plane. A first director element is spaced above the driven element and has lesser length and width dimensions than the driven element. A second director element is spaced above the first director element and likewise has lesser length and width dimensions than the driven element. A group of eight of the antennas are positioned in a column to form an antenna array which has substantial vertical polarization, a relatively wide horizontal beam width, approximately 60.degree. and a relatively narrow vertical beam width, approximately 8.0.degree.. The antenna array has a center frequency of 885 Mhz and a bandwidth of approximately 230 Mhz.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: April 26, 1994
    Assignee: Allen Telecom Group, Inc.
    Inventor: Tan D. Huynh
  • Patent number: D367480
    Type: Grant
    Filed: January 5, 1995
    Date of Patent: February 27, 1996
    Assignee: Allen Telecom Group, Inc.
    Inventor: James A. Bacnik
  • Patent number: D367481
    Type: Grant
    Filed: January 5, 1995
    Date of Patent: February 27, 1996
    Assignee: Allen Telecom Group, Inc.
    Inventor: James A. Bacnik