Showing papers on "Feed line published in 1999"

Antenna feed and a reflector antenna system and a low noise (lnb) receiver, both with such an antenna feed

Abstract: The present invention relates to antenna feeds (10, 30, 70, 78, 94) for use in linear or circularly polarised systems. In one embodiment of the invention, a cross-type antenna feed (30) comprises a cylindrical metal waveguide housing (12) and a cross-type metal feed body (32) coupled to the front of the waveguide housing (12). The feed body (32) has four peripherally spaced corrugated arm portions (34) arranged in a mutually orthogonal relationship, where the arm portions (34) extend radially outwardly from a longitudinal axis (16) of the feed body (32). Ridges (36) on each arm portion (34) are arranged concentrically around the axis (16) and parallel thereto, with successive ridges spaced from the axis (16) in a tiered arrangement. In another embodiment the antenna feed is a dielectric lens. The antenna feed is used in an antenna system having a reflector antenna in addition or in a low noise block (LNB) receiver.

Directional coupler, antenna device, and transmitting - receiving device

Abstract: A first transmission line and a second transmission line are caused to be partially opposite to each other, and by use of the opposite portions of the first transmission line and the second transmission line, the first transmission line and the second transmission line are relatively shifted in parallel from their opposite state to their non-opposite state.

Transmitter incorporating spatio-temporal processing

Abstract: A space-time signal processing system with advantageously reduced complexity. The system may take advantage of multiple transmitter antenna elements and/or multiple receiver antenna elements, or multiple polarizations of a single transmitter antenna element and/or single receiver antenna element. The system is not restricted to wireless contexts and may exploit any channel having multiple inputs or multiple outputs and certain other characteristics. Multi-path effects in a transmission medium cause a multiplicative increase in capacity.

Coaxial type signal line and manufacturing method thereof

Abstract: Disclosed is a coaxial type signal line that solves problems associated with signal interference and the connection of signal lines that are generated in a radio frequency (RF) electrical system. A method for manufacturing the coaxial type signal line includes the steps of forming a groove on a substrate, forming a first ground line on a surface of the groove and a plain surface of the substrate, forming a first dielectric layer including dielectric material on the first ground line formed on the surface of the groove, forming a signal line on the first dielectric layer the signal line for transmitting signals, forming a second dielectric layer including dielectric material on the signal line and the first dielectric layer, and forming a second ground line on the first ground line and the second dielectric layer. Since the signal line in the signal line structure according to the present invention is electrically shielded by the first and second ground lines, interference between the signal line and other signal lines on the semiconductor substrate can be prevented, and accordingly, the signal lines may be designed compactly on a semiconductor substrate and the system size can be reduced.

Feed structures for tapered slot antennas

Abstract: A suspended microstrip line structure for feeding a tapered slot antenna has a ground layer separated by means of an air gap from a dielectric slab with a strip line conductor feed running on the surface of the dielectric. The strip line may run along the surface of the dielectric which faces away from the ground layer, or the structure may be inverted such that the strip line runs along the surface of the dielectric which faces the ground layer. These suspended microstrip line structures exhibit lower transmission loss. In another embodiment, a printed transmission line having a slot in its ground layer feeds a tapered slot antenna element which lies in a plane which intersects, and so is not parallel to, the printed transmission line structure. The ground layer slots cut the current on the ground of the transmission line and couple energy from the line to the tapered slot antenna element. Altering the configuration of the ground layer slots allows the antenna to efficiently operate within different frequency bands without changing the dimensions or parameters of the tapered slot antenna or the printed transmission line. The printed transmission line is preferably a suspended microstrip line. One and two dimensional arrays of these antenna elements fed by a parallel beam forming network (BFN) may also be assembled.

Moveable antenna employing a hybrid RF and DC circuit

Abstract: A moveable antenna system with a position sensor circuit and a circuit which transmits the position sensing data and the radio frequency (RF) on the same wire. The position sensor comprises a sensing pin and a sense track concentric with the coaxial cable for the RF signal. When the antenna is in the preferred position for transmission, the sensing pin is in contact with the sense track, thus closing a switch, allowing the unit to transmit RF signals. Otherwise, the sensing pin is not in contact with the sense track, preventing any transmission of data. The signal that results from the opening and closing of the switch is carried on the same transmission line as the RF signal. This is accomplished by using capacitors to block direct current (DC) from the transmission line and using resistors and shunt capacitors to prevent any leakage of RF signals onto the sensing circuit.

Array antenna device and radio equipment

Abstract: A dielectric line has a conductor plate and dielectric strip on the side of a fixed portion and a dielectric line including a conductor plate and dielectric strip on the side of a moving portion. A directional coupler comprises the dielectric lines. On a dielectric plate of an array antenna portion a plurality of linear array antennas are formed and connected to a microstrip as a feed portion. By displacement of the moving portion, the feed point to the feed portion is changed and the feed phase to each linear array antenna and the feed power to each element antenna are changed. Thus, the direction of a beam is changed.

Planar transmission line to waveguide transition for a microwave signal

Abstract: A transition from a planar transmission line to a waveguide has a planar transmission line patterned onto a glass substrate. A mode transformer 1 on the substrate 3 is electrically connected to a transmission line 2 and converts a transverse electric or quasi-transverse electric mode signal carried by the transmission line to a waveguide mode signal. A combination of a first extension of the substrate 3 and a dielectric portion having some depth makes up a first impedance matching element 13. A second impedance matching element 14 is a combination of a second extension of the substrate 3 and a dielectric portion having another depth greater than the first depth. The aperture created by the second impedance matching element launches an RF signal into the air for use as a wireless communication signal. Also disclosed is a method for optimizing a transition according to the teachings of the present invention for alternative dimensions and dielectrics.

Phase-tunable antenna feed network

Abstract: The invention is a device that provides a phase-tunable antenna feed network that allows beam-steering and beam-width variation with simple actuation, at low cost, and with high rf performance. The device provides a series-feed where signal power splitters and phase-shifters are alternately disposed in series. Each phase-shifter consists of reflection-mode phase-shifter elements that operate in conjunction with an isolation device. This avoids the critical resonance condition between periodically aligned phase-shifters over the entire tuning range, since the isolation devices can easily be matched and/or aligned with non-resonant spacing. The main feed-line interconnections have the same impedance, thereby enabling the utilization of the same phase-shifter design for the entire network. Moreover, a common driving mechanism can be used for the phase-shifters to steer the antenna beam. Splitting the array into two sub-arrays with individual collective driving mechanism further allows beam-width variation by steering the beams of both sub-arrays in opposite directions. The device is further compatible with symmetrical series network designs that have better frequency response. The series feed network preferably uses a phase-shifter for shifting a signal propagating through a transmission line by moving a conductive construct between an active line and a ground plane of the transmission line. The conductive construct capacitively couples with either the active line and/or the ground plane, forming a capacitive shunt that reflects a significant part of the signal. The remaining portion of the signal is reflected at a terminated end of the transmission line, resulting in substantially no signal loss.

Antenna impedance adjuster

Abstract: There is provided an antenna impedance adjuster including (a) an antenna through which radio signals are received and transmitted, (b) a radio signal receiver which receives radio signals having been received through the antenna, (c) a radio signal transmitter which transmits radio signals through the antenna, (d) an adjuster which matches an impedance between the antenna and the radio signal receiver in radio signal receiving band and an impedance between the antenna and the radio signal transmitter in radio signal transmitting band, (e) a first switch which electrically connects the adjuster to one of the radio signal receiver and the radio signal transmitter, and (f) a controller which controls an operation of the first switch when a radio signal is received or transmitted. The antenna impedance adjuster reduces transmission loss to be generated between an antenna and internal circuits to thereby enhance output-load characteristic in a radio signal transmitting circuit, and prevents degradation of sensitivity in a radio signal receiving circuit.

Method and arrangement for the indirect cooling of the flow in radial gaps formed between rotors and stators of turbomachines

Abstract: A method of cooling the flow in radial gaps formed between rotors and stators turbo machines is provided. The method includes the step of using water as a cooling fluid for the stator part adjacent to the radial gap. To this end, either at least one recess is formed in the interior of the stator part adjacent to the radial gap or at least one cavity is arranged at the stator part. The recess or the cavity is connected to both a feed line and a discharge line for the cooling fluid.

Transmission antenna diversity

Abstract: In mobile communications systems transmission antenna diversity is used e.g. to compensate for fading caused to the signal on the radio path. It is known to make the choice of transmission antenna jointly for all subscriber connections, but it is not hereby possible to offer the optimum transmission antenna to simultaneous connections. The present invention aims at a method for implementing transmission antenna diversity on a data transmission connection, which is set up between a transmitting unit (BS), wherein there are several transmission antenna routes (ANT1, ANT2, ANT3), and a receiving unit (MS1, MS2). In the method, a broadcast signal is transmitted through all transmission antenna routes (ANT1, ANT2, ANT3) of the transmitting unit, with the aid of these signals a choice is made in the receiving unit (MS1, MS2) of the optimum transmission antenna route and a message of the choice is transmitted to the transmitting unit (BS), which transmits user data through the transmission antenna route connected for use. According to the invention, the method is characterised in that the broadcast signal of each transmission antenna route is shaped by an individual signal shaping method which is different from the others and a transmission antenna route is connected for use based on the received antenna choice message, individually for each receiving unit.

System for communicating over a transmission line

Abstract: A system for communicating over a transmission line has a plurality of transceivers, each for generating an information signal for transmission over the transmission line and for reception of an information signal transmitted thereto over the transmission line. A device couples each transceiver to the transmission line. The device includes a ferrite core surrounding the transmission line and at least one winding extending through the core and connected to the transceiver. As a result, the current signal corresponding to a generated information signal, as applied to the transmission line during transmission, and a current signal corresponding to a transmitted information signal is received From the transmission line during reception.

Input impedance characteristics of coaxial slot antennas for interstitial microwave hyperthermia

Abstract: In this paper, a transmission-line type of input impedance model originally developed by King et al. (1983) for the insulated dipole antenna embedded in a homogeneous dissipative medium is extended to the case of insulated coaxial slot antenna. Physical construction of the latter indicates the presence of additional current path(s) inside the feed line, which shall lead to the shortening of its resonance length. This effect is taken into account in the impedance model and verified by experiments. Furthermore, a simple strategy for optimizing the applicator's impedance-matching performance is also described and verified. Excellent agreements observed between theoretical and measured S/sub 11/ data indicate that these models can be relied upon when designing an efficient applicator for interstitial microwave hyperthermia.

Parametric study and temperature sensitivity of microstrip antennas using an improved linear transmission line model

Abstract: An improved linear transmission line (LTL) model has been developed after incorporating several modifications in the reported linear transmission line model for analyzing arbitrarily shaped microstrip antennas (MSAs), which should be symmetrical with respect to the feed axis. Simulations have been carried out for rectangular, circular, and equilateral triangular MSAs and the results are in good agreement with reported results. A parametric study for these MSAs has also been performed. A study of the temperature sensitivity for rectangular MSAs for different types of substrates has been carried out. An MSA utilizing a substrate with a lower dielectric constant and thermal coefficient is less sensitive to temperature variations.

Method and apparatus for coupling a microstrip transmission line to a waveguide transmission line for microwave or millimeter-wave frequency range transmission

Abstract: A microstrip transmission line to waveguide transmission line transition. A microstrip transmission line is separated from a ground plane by a dielectric therebetween. The microstrip transmission line terminates at a microstrip transmission line open circuit end. A waveguide channel having narrow dimension waveguide walls and a broad dimension base waveguide wall connected therebetween is provided. The waveguide channel has a waveguide short circuit wall located along the channel. The narrow dimension waveguide walls are coupled with the ground plane to provide a broad dimension top waveguide wall for the waveguide transmission line. An aperture is located transverse to the microstrip transmission line and passes through an aperture ground plane opening in the ground plane. The aperture is located proximate to the microstrip transmission line open circuit end to provide a microstrip transmission line open circuit stub and proximate to the waveguide short circuit wall to provide a waveguide transmission line short circuit stub.

Radio transceiver switching circuit

Abstract: The invention is related to a radio transceiver circuit comprising an antenna (21), a transmitter (11), a receiver (12), an antenna switching circuit for selectively connecting the transmitter (11) and the receiver (12) to the antenna (21), and a power source (24) for driving the transmitter and the receiver. The antenna switching circuit is having two semiconductor elements (15,16), e.g. PIN diodes. The current (IBRX, IBTX) provided by the power source (24) to the receiver (12) and to the transmitter is directed through the respective semiconductor element (15,16) which is set to its conductive electrical state by the respective current (IBRX, IBTX) and thereby selectively coupling the radio signal between the receiver (12) and the transmitter (11) to the antenna (21). The invention is furthermore related to a method of operating a semiconductor element switch of a transceiver circuit.

Connection structure between dielectric waveguide line and high frequency line conductor

Abstract: PROBLEM TO BE SOLVED: To obtain a connection structure between a dielectric waveguide line and a high frequency line conductor electromagntically connecting the stacked dielectric waveguide line and the high frequency line conductor such as other microstrip line or coplanar line through the use of a slot hole 7 while keeping an excellent characteristic even when the characteristic impedance of the both differs. SOLUTION: The connection structure is configured such that a high frequency line conductor 8 placed opposite to a slot hole 7 is electromagnetically coupled with a dielectric waveguide line 6 provided with main conductor layers 2, 3 clamping a dielectric board 1, two-lines of side wall use through-conductor groups 4, and a sub conductor layer 5 in parallel with the main conductor layers 2, 3, a short-circuit end by end face use through-conductor groups 9 and an end face use sub conductor layer 10 is formed at a position distant from the slot hole 7 of the dielectric waveguide line 6 by about a multiple of n/2 of a guide wavelength in a transmission direction, and an inner conductor layer 11 reaching a lower part of the slot hole 7 from a short-circuit end is formed at a height from the main conductor layer 3 by less than 1/4 of the waveguide length. The characteristic impedance of the connected parts of the both can be matched by using the short circuit end and the inner conductor 11 and the connection structure with an excellent characteristic is realized by suppressing the reflection.

Antenna for a wireless communication module

Abstract: An antenna (28) for use in a wireless communication module (10) includes a shield plate (40), an antenna loop element (42), and a transmission line element (44). The wireless communication module (10) also includes a receiver (37) having a circuit board (30). The shield plate (40) is located on a first side (32) of the circuit board (30); and the antenna loop element (42) and the transmission line element (44) are located on an opposite side (34) of the circuit board (30). The shield plate (40) is electrically connected to a first loop end (50) of the antenna loop element (42). A capacitor (64) interconnects a second loop end (52) of the antenna loop element (42) to a first transmission line end (58) of the transmission line element (44). A second transmission line end (60) is electrically open.

Integrated circuit and method for minimizing clock skews

Abstract: An integrated circuit interconnection comprising a transmission line having a low characteristic impedance, and including a first end and a second end. A driver is coupled to the first end of the transmission line, and the transmission line is terminated with a current sense amplifier having an input impedance corresponding to the characteristic impedance of the transmission line. A plurality of components selected from the group consisting of capacitive elements, inductive elements and a combination of capacitive and inductive elements are connected at spaced intervals to the transmission line between the first and second ends.

Microstrip patch radiator with means for the suppression of cross-polarization

Abstract: A dual polarized microstrip patch radiator comprising a ground plane, a thin layer of dielectric on each side thereof, a conductive microstrip patch on a first of the dielectric layers on a side remote from the ground plane, first and second feed lines on the side of the second dielectric layer remote from the ground plane, first and second pairs of apertures in the ground plane the second pair of apertures being orthogonal to the first pair of apertures, the first feed line being radiatively coupled to one of the first pair of apertures and not radiatively coupled to the other aperture of the first pair of apertures nor to the second pair of apertures, the second feed line being radiatively coupled to one of the apertures of the second pair of apertures and not radiatively coupled to the other of the second pair of apertures nor to the first pair of apertures, the other aperture of the first pair of apertures being positioned to provide a symmetrical boundary condition for power coupled from the second feed line, and the other aperture of the second pair of apertures being positioned to provide a symmetrical boundary condition for power coupled from the first feed line, whereby cross-polarization of the feeds is minimized.

Characteristics of digital terrestrial broadcasting antennas

Abstract: The characteristics of the batwing radiator, which is the heart of the superturnstile antenna system for VHF-TV broadcasting, are broad bandwidth. We investigate the modified batwing antenna for UHF used for digital terrestrial broadcasting. The characteristics of the 2-element modified batwing antenna with an infinite reflector and with a wire screen for the finite reflector are calculated by NEC-Win Pro. These antennas are connected with each element by a parallel feed line and fed at the center of this line. We estimate these antennas from 470 MHz to 770 MHz of the UHF-TV broadcasting band in Japan. The broad-band properties and the power gain of about 11 dBi are obtained in these frequencies.

Polyhedral-shaped redundant coaxial switch

Abstract: A three dimensional microwave switch having a plurality of waveguide transmission lines configured in an octahedral shape having microwave I/O ports at the corners. Individual actuators selectively move respective reeds within the waveguide transmission lines between a signal-attenuating position abutting the interior surface of the waveguide transmission line and a signal-conducting position substantially coaxial with the waveguide transmission line and abutting the signal lines of the I/O microwave ports couple to opposite ends of the waveguide transmission line.

Fuel cell system has gas compressor connected to air feed line from compressor to fuel cell, recovery unit in waste gas line, liquid-gas separator unit, water feed line and pressure feed device

Abstract: The fuel cell system has a fuel cell (10) with at least one air inlet and waste gas outlet, a gas compressor (11) connected to the air feed line (12) carrying process air from the compressor to the fuel cell, a recovery unit (15) in the waste gas line (13), a liquid-gas separator unit (14) between the cell and recovery unit with a storage container (14b) for separated water, a water feed line (20) between the storage container and compressor and a pressure feed arrangement for using the waste gas pressure to force the stored water into the water feed line.

Antenna of a radio device and a method to manufacture it and a radio device

Abstract: A radio device comprises an antenna for transmitting and receiving radio frequency signals. The antenna comprises a radiating antenna element (201, 602, 701) and a dielectric protective casing (202, 703) attached to each other, whereby the dielectric protective casing substantially encloses the antenna element. Further the radio device comprises a protective casing (205) of the radio device for mechanically supporting the radio device and for protecting its electrical components, and a printed circuit board (203) within the protective casing for connecting the electrical components to the radio device and for forming the electrical connections between the components. The antenna is mechanically fastened to the radio device with the aid of counterpart fastening shapes (301, 302, 303, 304, 305, 306, 307, 308) located in the antenna's protective casing and in the radio device's protective casing. The antenna is electrically connected to the radio device by a connection between a certain point (201b, 201b') of the radiating antenna element and a certain point (204, 204', 402) of the radio device.

Electromechanical phase shifter for a microstrip microwave transmission line

Abstract: An electromechanical phase shifter for a microstrip microwave transmission line includes a conductive base plate and a pair of microstrip transmission line segments supported parallel to each other and parallel to and spaced from the base plate. A movable microstrip transmission line bridges the pair of transmission line segments and is movable therealong to provide a short circuit therebetween. A movable ground element is coupled to the bridging transmission line for movement therewith and is in contact with the pair of transmission line segments and the base plate. The spacing between the movable bridging transmission line and the ground element is maintained at one quarter wavelength of the center frequency of the signal frequency band.

An antenna system and a radio communication device including an antenna system

Abstract: An antenna system including an antenna device and feed device for transmitting and receiving circularly polarised RF waves in a first mode of operation and of linearly polarised RF waves in a second mode of operation, and a hand-held mobile communication device provided with such an antenna system. A radiating structure (10) including N helical radiating elements (12A-D), being coextending and coaxially arranged on a support structure (11) are fed in order to provide for transmission/reception of circularly polarised RF waves in the first mode of operation. N is an integer greater than one. Further, means (24A-D, 16, 17, 19, 25, 25A) are arranged for essentially uniform excitation of the helical radiating elements (12A-D) in order to provide for transmission/reception of linearly polarised RF waves in the second mode of operation.

Broadband coupler for measurement of antenna signals

Abstract: A selected length of antenna for a device under test is placed within a conductive inner cylinder, forming an unterminated “input” coaxial transmission line. The inner cylinder is in turn within and coaxial with a conductive outer cylinder, forming an “output” transmission line. The inner cylinder is the center conductor of the output transmission line, and in a region extending beyond the extent of the antenna therein, conically tapers to being a normal center conductor of solid cross section. The outer cylinder matches this taper to maintain a constant characteristic impedance Z 0out (say, 50 Ω) for the output transmission line, which then delivers its output signal to a matched terminating load in measurement equipment via either a coaxial connector or an interconnecting length of auxiliary transmission line. These triaxially nested input and output transmission lines are supported at a driven end by an RF tight box that contains a mounting fixture to support the device under test in a fixed and appropriate relation to the triaxially nested input and output transmission lines, and that is lined with anechoic RF absorbing material.

Connection structure between coaxial connector and planer circuit board

Abstract: PROBLEM TO BE SOLVED: To provide a connection structure that a eliminates impedance mismatchings caused at a connection part between a coaxial line and a strip line. SOLUTION: An in-case coaxial line 2-1 has a coaxial line 2-2 with a capacitive reactance, the radius of the outer conductor of which is smaller than a coaxial line 2-4 giving the characteristic impedance and is structured, such that the coaxial line 2-2 is sandwiched in between coaxial lines 2-3, 2-4, whose impedance is equal to the characteristic impedance. A center conductor of the coaxial line 2-1, as shown in a connection part 2-1 in Figure connects the coaxial line 2-1 and a microstrip line 3. Furthermore, a common ground 3-1 of the microstrip line 3 is connected to a case 1 to form the same common ground as for the case 1. COPYRIGHT: (C)2001,JPO

Microstrip antenna having an internal feed

Abstract: A one half wavelength microstrip antenna which has its structural feed po positioned in a location which is different from the location of its electrical feed point. The microstrip antenna comprises a disc-shaped dielectric which has a radiating patch mounted on its upper surface and a ground plane affixed to its lower surface. Attached to the bottom surface of the ground plane is a threaded coaxial cable connecter for receiving a coaxial cable which supplies a microwave signal to the microstrip antenna. Extending vertically upward from the connector is a center contact pin which electrically couples the antenna element to the coaxial cable. The antenna element includes a V-shaped element of etched copper which has its rounded bottom portion positioned adjacent the center contact pin. The area enclosed by V-shaped element of etched copper forms a 50 ohm transmission line which electrically connects the center contact pin to the antenna feed point of the microstrip antenna which allows for the transmission of the microwave signal from the center contact pin to the antenna feed point.