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9 records (took 0.019 seconds)

    1.
    发明专利
    未知

    公开(公告)号：AT271263T

    公开(公告)日：2004-07-15

    申请号：AT01403159

    申请日：2001-12-07

    Applicant: CIT ALCATEL

    Inventor： MCDONALD NOEL ,  WILLIAMS CHARLIE G

    IPC: H01P1/18 ,  H01Q3/36

    Abstract: A phase shifting element for controllably varying the phase of signals of desired frequencies or frequency range passing along an adjacent transmission line section associated with, for example, an antenna array to electrically down-tilt the array's electromagnetic wave pattern. The phase shifting element includes a planar dielectric member having at least three discrete co-planar interactive segments extending from an edge thereof and arranged to movably overlap or intersect or interleave the transmission line section to vary its effective electrical length. Optimum dimensions of each interactive segment and optimum widths of gaps defined by facing edges of adjacent segments are determined by a computer optimisation program, such that the phase shifting element achieves a wide operating frequency range and minimum aggregate signal reflection.

    DUAL BAND COMBINER ARRANGEMENT
    4.
    发明专利
    DUAL BAND COMBINER ARRANGEMENT 未知

    公开(公告)号：CA2273669A1

    公开(公告)日：2000-02-07

    申请号：CA2273669

    申请日：1999-06-07

    Applicant: CIT ALCATEL

    Inventor： MCDONALD NOEL ,  PELZ DIETER

    IPC: H01P1/213 ,  H04J1/08

    Abstract: A dual band combiner for combining two frequency bands having a 2:1 relationship, e.g. 900MHz and 1800MHz. The combiner comprises and upper frequency bandpass filter section and an upper frequency bandstop filter. The bandpass filter section comprises two open-end resonations whose lengths are 1/2 wavelength of the upper frequency band, and the bandstop filter comprises three open-end resonators whose lengths are 1/4 wavelength of the upper frequency band. Because of the 2:1 frequency relationship pronounced selectivity-enhancing transmission zeros are produced at the lower frequency band, thereby providing a combiner that has high isolation between ports while maintaining low insertion loss.

    WAVEGUIDE DIRECTIONAL FILTER
    6.
    发明专利
    WAVEGUIDE DIRECTIONAL FILTER 未知

    公开(公告)号：CA2352875A1

    公开(公告)日：2000-06-15

    申请号：CA2352875

    申请日：1999-12-06

    Applicant: CIT ALCATEL

    Inventor： BROAD GRAHAM ,  MCDONALD NOEL ,  WILLIAMS CHARLES

    IPC: H01P1/213 ,  H01P1/208

    Abstract: A waveguide directional filter is described for combining multiple high powe r UHF television broadcasting transmitters on to a common antenna. The filter arrangement comprises an input waveguide (1) and an output waveguide (2). Th e waveguides are rectangular having broad walls (3) joined by narrow walls (4) whose width/height ratio is approximately 4:1. The two waveguides are connected by at least one direct-coupled cavity resonator (5). Coupling between the cavity and each waveguide is obtained by a respective characteristic aperture (7, 7a) in the form of a rectangle whose four sides have inwardly extending hemicycle sectors (8, 9, 10 and 11).

    7.
    发明专利
    未知

    公开(公告)号：BR9916459A

    公开(公告)日：2001-09-04

    申请号：BR9916459

    申请日：1999-12-06

    Applicant: CIT ALCATEL

    Inventor： BROAD GRAHAM ,  MCDONALD NOEL ,  WILLIAMS CHARLES

    IPC: H01P1/213 ,  H01P1/208

    Abstract: A waveguide directional filter for combining multiple high power UHF television broadcasting transmitters on to a common antenna. The directional filter arrangement includes an input waveguide, an output waveguide and an interconnected cascade assembly of two or more cavity resonators. The input and output waveguides are each aperture-coupled to an end cavity resonator of the cascade assembly. The edges of each aperture incorporate inwardly extending curved protrusions of a characteristic shape. Alternatively or additionally, at least one pair of non-adjacent cavity resonators are coupled by at least one additional coupling element incorporating an external transmission line.

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