Abstract: The cost of an antenna duplexer is reduced by decreasing the number of parts for antenna switching, and the size thereof is reduced by reducing the space of a printed-circuit board on which a receiving circuit and a transmission circuit are formed. The antenna duplexer includes an antenna, a transmission circuit, a receiving circuit, a first transmission line for connecting the transmission circuit to the antenna, and a second transmission line for connecting the receiving circuit to the antenna, wherein the length of the first transmission line is set to be approximately a quarter of the wavelength of the transmission frequency, and the length of the second transmission line is set to be approximately a quarter of the wavelength of the receiving frequency.
Abstract: A dielectric filter includes a dielectric ceramic block having the shape of a rectangular prism and including three or more through-holes formed therein in parallel. An inner conductor covers the inner surface of each of the through-holes to form the corresponding resonator. An outer conductor covers a predetermined outer surface of the dielectric ceramic block, excluding the open end surface. Input/output pads are formed on one side surface of the dielectric ceramic block such that the pads face the two end resonators. Each of the through-holes of the end resonators is provided with a counterbore. An auxiliary conductor is disposed on the open end surface to face at least one intermediate resonator between end resonators. The auxiliary conductor at least partially surrounds the intermediate resonator with an insulating gap formed therebetween, and is connected to the outer conductor on the side surface on which the input/output pads are provided.
Abstract: A circuit that prevents a receiving signal from leaking to an LNB supply line to thereby deteriorate input VSWR characteristic includes a capacitor of about 1000 pF for removing noise and a capacitor of about 1 pF for passing a high frequency component which leaks to an LNB voltage supply line to the ground provided between the LNB voltage supply line and the ground. By the capacitor of about 1000 pF, a noise component included in the LNB voltage supply line is removed. Further, by the capacitor of about 1 pF, the high frequency signal component which leaks via a choke coil is bypassed to thereby reduce impedance of a node NA over a broad band and prevent a reflecting wave from being produced at the node NA and input VSWR from being deteriorated.
Abstract: An object of the present invention is to provide an NRD guide which can be used in a wide band in a state where output levels of distributed high-frequency signals are nearly equal and does not require precise positioning, thereby enhancing mass productivity thereof. The NRD guide comprises a first straight dielectric strip made of cordierite ceramics having a dielectric constant of 4.8 and a dielectric loss of 2.7×10−4 (at a measurement frequency of 77 GHz) and having a section of 1.0 mm width×2.25 mm height, and a second dielectric strip joined to the first dielectric strip at a midway position thereof so as to be branched along an arc and bent at an angle of 90°, wherein the first and second dielectric strips are integrally produced, and the radius of curvature r of a junction (branched portion) of the second dielectric strip is 12.7 mm, which is larger than the wavelength &lgr;≈5 mm of high-frequency signals of 60 GHz.
Abstract: In a waveguide twist having a torsion element with at least three individual parts situated adjacent to each other and rotatable around an axis of the torsion element, in which each of the individual parts has a central passage hole with a cross-section corresponding to the open cross-section of the waveguides, and in which the passage holes of the individual parts in a non-rotated condition of the torsion element are aligned with each other, a recess is formed in one face of each of the individual parts, the extent of the recess in circumferential direction corresponding to a specified angle of rotation; from the other face of the individual parts a pin extends in an axial direction; and in a mounted position of the torsion element a pin projecting from one individual part engages in the recess located in the face of the adjacent individual part.
Abstract: A shielded modular tuner is horizontally mounted onto a chassis printed circuit board and is provided, through an aperture in the shield, with lead connections from the edge of the tuner printed circuit board to the chassis printed circuit board, for power supply, control signals, outputting a processed signal, etc. The RF signal is coupled to the tuner via a conductive pin/lead extending from an RF signal conducting path on the chassis printed circuit board, passing through a second aperture in the shield, directly to the point on the tuner printed circuit board where the signal is to be inputted for tuner processing. In this way, the RF signal is injected directly into the tuner precisely where it is needed without being led along a longer and possibly meandering path from the edge of the tuner printed circuit board, and without a shielded coaxial cable and accompanying connectors.
June 9, 2000
Date of Patent:
June 11, 2002
Thomson Licensing, S.A.
Edward Allen Hall, Tey Tiam Fatt, Pang Kim Suan
Abstract: A balun transformer having two series connected transformers with each having a primary loop conductor disposed in a stacked configuration. One portion of each primary loop conductors is in a first layer and these two portions of the two primary loop conductors are connected in series. The second portions of the primary loop conductors are in a second layer that is spaced from the first layer with the secondary loop conductors interlaced with these portions of the primary loop conductors in the second layer.
August 24, 2000
Date of Patent:
April 30, 2002
International Business Machines Corporation
James F. Imbornone, Jean-Marc Mourant, Daniel Shkap, Tao Liang