Showing papers on "Feed line published in 1996"

Short vertical 160 meter band antenna

Abstract: A physically short broad-bandwidth multiband vertical antenna with 50 ohm input impedance and 25 foot square footprint for 160, 80, 40 and 17 meter radio bands Low ohmic resistance due to the small physical size combined with system impedance transformation and capacitive input coupling provide radiation resistance corresponding to an efficiency of about 85 percent The 2:1 SWR bandwidth is 50 kHz on 160 meters and 87 kHz on 80 meters A 30 foot mast, top hat capacitive load, and a plurality of parallel vertical skirt wires depending from the top hat around the mast are electrically connected together at the top of the mast An impedance transforming multi-tap coil is connected between mast and ground Skirt wires are in two sets separately fed at their lower ends by separate coaxial cable coupling capacitors for operation on different bands A 50 ohm feed line, skirt wires, coupling capacitors and impedance transforming coil all have terminal connections on a mast-base insulator End-pruning of coaxial cable capacitors combined with coil tap selection tunes the antenna for desired portions of the 160 and 80 meter bands for input impedance matching without additional matching devices Skirt wire sets, downwardly tensioned and spaced from the mast, are connected to input capacitors by separated crossed metal spreaders at the mast-base insulator Additional reactance-reducing components facilitate improved operation at 40 meters More independent center frequency tuning for both 160 and 40 meter bands is obtained by connecting the impedance transformation coil from ground to a higher point on the mast via an additional skirt system

Radio communication system using portable mobile terminal

Abstract: A radio communication system comprises a transmitting antenna for transmitting radio signals. Each radio signal is transmitted via one of a plurality of beams of different maximum radiated directions. The system also comprises a transmitting section for adding to a radio signal, transmitted via an i-th beam among the plurality of beams, beam identification information that identifies on which i-th beam of said plurality of beams said radio signal is being transmitted. The system further comprises a receiving antenna for receiving the radio signals transmitted by the plurality of beams and a receiver for selectively receiving a signal transmitted by a specific beam according to a predetermined estimation standard. Alternatively, the system may comprise a first radio station and a second radio station. The first radio station may include a transmitting antenna for transmitting signals with beam identification numbers and a receiving antenna for receiving signals from other radio stations. The second radio station may include a receiving antenna capable of receiving signals transmitted by the first transmitting antenna and a receiver for selectively receiving a signal transmitted by a specific beam according to a predetermined estimation standard. The second radio station may also include a transmitting antenna that forms a wide-angle beam to transmit the specific beam.

Movable dielectric body for controlling propagation velocity in a feed line

Abstract: A feed line structure (1), especially integrated with a stationary array of antenna elements so as to enable adjustment of the direction of the beam radiated from the array. The feed line structure comprises a feed conductor line pattern (3) disposed on a fixed carrier plate (2) at a distance from and in parallel to a fixed ground plate (4), and a movable dielectric plate (5) located therebetween. The feed line pattern (3) is elongated in the same direction (A) as the movement direction of the dielectric plate (5). The propagation velocity of the signal components is reduced by the dielectric plate (5), whereby a controlled phase difference between the various signal components is obtained.

Radio having a self-tuning antenna and method thereof

Abstract: A radio (100) includes a receiver circuitry (106) for use in conjunction with a tunable antenna (101) The radio includes a controller (122) which may be a digital signal processor The controller (122) controls various radio functions including tuning of the antenna (101), measurement of the quality of received signals, and generation of a test signal The radio is capable of generating a test signal on a desired frequency, which is radiated within the radio, received at the antenna (101) and then processed by receiver circuitry (106) Its quality is then measured and used to control the tuning of the antenna (101) The test signal generated by the controller (122) can be mixed up to the desired frequency by using one or more of the local oscillator signals of the radio

Electronic beam steering in wire and patch antenna systems using switched parasitic elements

Abstract: We explore the application of two alternative methods of electronically controlling the radiation pattern from an antenna array which has a single feed line. Type (a) involves switching one of the parasitic elements to become active. Type (b) requires switching the parasitic elements located in the vicinity of the active element between short circuit (i.e. continuous conduction in the element) and open circuit at a point where the induced current is minimised. Both techniques offer a reduced radiation loss in the feed network and relatively simple control circuitry and tracking software.

Fast transmission line implemented with receiver, driver, terminator and IC arrangements

Abstract: A signal transmitting circuit includes one or more circuit blocks having a driving circuit and an intra-block transmission line for transmitting a signal produced by the driving circuit, one or more circuit blocks having a receiving circuit and an intra-block transmission line for transmitting the signal to said receiving circuit, and a main interblock transmission line for propagating a signal between both of the driving and receiving circuit blocks. Inter-block transmission line is terminated at one or two ends by one or two resistors having substantially the same impedance as the interblock transmission line itself. Each of the intra-block transmission line is provided with a resistance element having a resistance equal to or close to a value derived by subtracting a half of an impedance of the inter-block transmission line from an impedance of the intra-block transmission line, to lower signal amplitude and suppress reflections of a signal at branch points along the main interblock transmission line, thereby enabling a high-speed signal transfer.

High frequency band high temperature superconductor mixer antenna which allows a superconductor feed line to be used in a low frequency region

Abstract: The invention provides a wide frequency band high temperature superconductor mixer antenna which allows a superconductor feed line, which exhibits a high resistance loss in a high frequency region, to be used in a low frequency region with a low loss and which is provided with a same structure as a mixer which has a wide band twice or more the frequency of a millimeter or more wave while keeping a characteristic of a high integration array antenna, which makes most of the high integrity of superconductor feed lines. The wide frequency band high temperature superconductor mixer antenna includes one or a plurality of planar structure antenna patterns of the log-periodical type or the log-spiral type and a plurality of oxide superconductor thin film feed line wiring patterns formed on a same face of a main surface of a substrate, a central portion of each of the planar structure antenna patterns being formed from an oxide superconductor thin film on which a non-linear element part is provided.

Radio telephone with separate antenna for stand-by mode

Abstract: A radio telephone for use in wireless telecommunication has a transmitter/receiver unit (4), a control unit (5), a first antenna (1), the properties of which are optimized for use in stand-by mode, and a second antenna (2), the properties of which are optimized for use during ongoing calls, said second antenna being electrically engageable and disengageable with the transmitter/receiver unit. The radio telephone further has an antenna switch (3), which is arranged to operatively connect the transmitter/receiver unit (4) to either the first antenna (1) or the second antenna (2), said antenna switch supplying the control unit (5) with control signals (7) in response to at least the electrical engagement status of the second antenna. The control unit prevents ingoing as well as outgoing calls from being established, as long as the second antenna according to said control signals is indicated to be electrically disengaged.

Waveguide-microstrip transmission line transition structure having an integral slot and antenna coupling arrangement

Abstract: A waveguide-microstrip transmission line transition structure is provided having a microstrip transmission line structure adapted for coupling to an open end of a waveguide. The microstrip transmission line structure includes a microstrip transmission line having a ground plane conductor and an antenna electrically coupled to the microstrip transmission line through an aperture in the ground plane conductor. The ground plane conductor is adapted for mounting in a plane intersecting a longitudinal axis of the waveguide. The antenna provides impedance matching between the microstrip transmission line and the waveguide. With such an arrangement, a relatively simpler manufacturable structure is provided because it is adapted for mounting to a standard waveguide flange and does not require specially machined waveguide pieces. The arrangement also provides modularity, in that the waveguide can be easily connected to and disconnected from the microstrip transmission line structure. Still further, the transition section does not require any special openings in the waveguide, thus eliminating spurious radiation and providing hermiticity. The structure is particularly well-suited for connecting planar antennas to waveguide feeds.

Modal expansion analysis of monopole antennas driven from a coaxial line

Abstract: A rigorous modal expansion analysis is presented for a monopole antenna fed through an infinite perfectly conducting ground plane by a coaxial transmission line. An infinite perfectly conducting plate is introduced to facilitate the use of the modal expansion method. The surface current and input impedance of the monopole antenna result from finding the expansion coefficients of the electromagnetic field expressions by enforcing boundary conditions at conducting surfaces and regional interfaces. Numerical results for the current distribution and input admittance of a parallel plate antenna and a monopole fed by a coaxial line are presented and compared with available data in the literature. Very good agreement is observed. Also examined is the effect of the junction between the feed line and the monopole on the antenna's admittance.

Apparatus and method for interline power flow control

Abstract: An apparatus (10) and method are disclosed for controlling the power flow in an electric transmission system including at least two transmission lines (12, 14), each transmission line having two ends and carrying alternating current at a selected transmission line voltage and fundamental frequency between the ends. At least two alternating voltages at the fundamental frequency of the alternating currents flowing in the transmission lines, with variable magnitude and controllable phase angle relative to the transmission line current, are generated and coupled in series with the transmission lines. The magnitude and phase of each generated voltage are controlled selectively and individually to adjust the effective reactive and real impedance of each transmission line, to control the real power transmitted between the two ends of the transmission line and, concurrently, to control the amount of real power individually transferred between the transmission lines.

Printed circuit antenna array using corner reflector

Abstract: A corner reflector antenna array capable of being driven by a coaxial feed line is disclosed herein. The antenna array comprises a substantially right-angle corner reflector having first and second reflecting surfaces. A dielectric substrate is positioned adjacent the first reflective surface, and defines first and second opposing substrate surfaces. In the preferred implementation the dielectric substrate is oriented substantially parallel to, but spaced from, the second reflective surface. The antenna array further includes a plurality of dipole elements, each of the dipole elements including a first half dipole disposed on the first substrate surface and a second half dipole disposed on the second substrate surface. A twin line interconnection network, disposed on both the first and second substrate surfaces, carries signal energy to and from the plurality of dipole elements. The segments of the interconnection network immediately proximate the dipole elements are preferably oriented normal to the radiation emitted thereby, and are thereby prevented from interfering with the antenna radiation pattern. A printed circuit balun is used to connect the center and outer conductors of a coaxial feed line to the segments of the interconnection network disposed on the first and second substrate surfaces, respectively.

Antenna changeover control system

Abstract: PROBLEM TO BE SOLVED: To easily provide transmission diversity. SOLUTION: A first radio station (base station) transmits test signals from a transmission antenna system 5 along with transmission information T1 and the characteristics of the transmission antenna system 5 are selected by an antenna switch device 4 controlled by a transmission controller 7. A second radio station (portable equipment) measures the quality of reception signals from the output of an electric field strength measurement part 20 and an intra- test-signal bit error rate measurement part 19, and when reception quality becomes lower than a prescribed value, transmits antenna switch signals to the first radio station along with the transmission information T2. In the first radio station 1 which receives the antenna switch signals, the characteristics of the transmission antenna system 5 are successively switched, the test signals are transmitted and the one of the best quality is selected from quality information corresponding to the respective antenna characteristics and used for the transmission of signals. COPYRIGHT: (C)1998,JPO

Interleaved planar array antenna system providing opposite circular polarizations

Abstract: An interleaved planar array antenna system providing opposite circular polarizations comprises an array of parallel rows of parallel spaced transmit dipole radiating elements and an array of parallel rows of parallel spaced receive dipole radiating elements. Both sets of dipole elements are on the same surface, with the receive dipole elements being oriented orthogonal to the transmit dipole elements and the rows of transmit and receive elements being interleaved. On another surface parallel to and spaced from the first surface, there is at least one transmit feed line which is proximity coupled to the transmit dipole elements and at least one receive feed line which is proximity coupled to the receive dipole elements. Polarizing means are spaced from and overly the transmit and receive dipole elements for transforming orthogonally oriented linearly polarized transmit and receive beams into oppositely circularly polarized transmit and receive beams.

Cooperative diversity antenna switching on transmitter and receiver side

Abstract: The pair of radio communication apparatuses of this invention on a transmitter side and a receiver side conduct data transmission and receiving through radio communication by a space diversity method where a plurality of antennas are switched therebetween, wherein the radio communication apparatus on the transmitter side includes a transmission circuit for conducting data transmission and a transmitting antenna switch circuit for selecting a transmitting antenna among a plurality of transmitting antennas for transmitting radio waves and connecting the selected transmitting antenna to the transmission circuit, and the radio communication apparatus on the receiver side includes a receiving circuit for conducting data receiving and a receiving antenna switch circuit for selecting a receiving antenna among a plurality of receiving antennas on the receiver side the radio waves and connecting the selected receiving antenna to the receiving circuit.

Reference signal generation in a switched current source transmission line driver/receiver system

Abstract: A reference generation and switched current source system suitable to convey data signals over a transmission line with minimum reflection through the use of active termination, transmission line current biasing, and the use of a shared referenced voltage derived from the characteristic impedance of the line as refined by integrated circuit transistor parameters at the transmitter and receiver. The integrated circuit chips connected by the transmission line each have a reference generator which defines a bias voltage for an active terminator, a bias current for injection into the transmission line, and a switched current source. The reference node interconnecting the transmitting and receiving devices conveys a voltage nominally twice the voltage at which the transmission line is biased and nominally twice the voltage increase introduced by the switched current source. The switched current source at the transmitting end, the bias current provided at the transmitting end, and the bias level of the active terminator at the receiving end of a transmission line are derived directly from the voltage on the reference node while compensating for the unique characteristics of the integrated circuit transistors in the respective chips.

Diversity radio communication system

Abstract: The pair of radio communication apparatuses of this invention on a transmitter side and a receiver side conduct data transmission and receiving through radio communication by a space diversity method where a plurality of antennas are switched therebetween, wherein the radio communication apparatus on the transmitter side includes a transmission circuit for conducting data transmission and a transmitting antenna switch circuit for selecting a transmitting antenna among a plurality of transmitting antennas for transmitting radio waves and connecting the selected transmitting antenna to the transmission circuit, and the radio communication apparatus on the receiver side includes a receiving circuit for conducting data receiving and a receiving antenna switch circuit for selecting a receiving antenna among a plurality of receiving antennas on the receiver side the radio waves and connecting the selected receiving antenna to the receiving circuit.

Power station with high-temp fuel cell (HTFC) stack and gas treatment plant

Abstract: A power generating plant having at least two fuel-cell stacks in which the first stack (1) comprises an internal or an external reformer thermally coupled on to the stack and with at least one gas treatment plant (10) arranged in the combustion gas feed line of the second stack (2). At least three further lines are provided next to the usual output and/or the anode chamber input of the first stack (1) to the input of the gas treatment-plant (10), a second line (9) joining the latter's output to the combustion gas line of the first and/or second stack (1,2) and a third line (5) joining the output of the anode chamber of the second stack to the combustion gas line (14) of the first stack and/or to the first line (4). A further line (6) is specifically provided and joins the cathode off-gas to the oxidant feed line (8) of the first stack so that the off-gas is fed out of the cathode space into the oxidant in feed line (8).

Microstrip-fed cylindrical slot antenna

Abstract: A microstrip-fed cylindrical slot antenna is provided for allowing better communication between an object and a satellite. The microstrip-fed cylindrical slot antenna comprises a cylindrical base member; a first conductive coating disposed on the cylindrical base member; at least one slot disposed in the conductive coating, the slot having a helical configuration about the cylindrical base member; and a feed line corresponding to each of the slots, the feed line crossing each respective slot and extending beyond the slot by a distance D.

Antenna-integrated strip line cable

Abstract: An antenna-integrated strip line cable with which it is possible to improve the performance of a high-frequency appliance such as a portable telephone without making the appliance larger. An antenna-integrated strip line cable 1 is made up of a transmission line part 2, an antenna part 3 and a counterpoise 4. The transmission line part 2 is made up of two conductors 21, 22 disposed in parallel, insulators 23, 24 having plasticity or flexibility disposed between these two conductors 21, 22, and a central conductor 25 disposed between the insulators 23, 24 centrally in the width direction thereof. Wide-pattern impedance matching circuits 26a, 26b are provided in the central conductor 25. The antenna part 3 has portions of the insulator 24 and the central conductor 25 extending from the transmission line part 2. The counterpoise 4 has portions of the insulator 23 and the conductor 21 extending from the transmission line part 2. The counterpoise 4 is perpendicular to the antenna part 3 and the length of the counterpoise 4 is about one-fourth of the wavelength λ of the frequency used. Some benefits of this novel construction are that the number of parts is reduced, the work of connecting a coaxial cable to an antenna is made unnecessary, the counterpoise reduces directivity of the antenna part, the antenna is tough, and it is not necessary to provide an impedance matching circuit externally.

Combined AM/FM/cellular telephone antenna system

Abstract: A combined AM/FM/cellular telephone antenna system comprises a coaxial cable with an upper portion of the inner conductor of the coaxial cable and an adjacent section of the coaxial cable together forming a cellular telephone dipole antenna. The coaxial cable forms a transmission line connecting the cellular dipole antenna to cellular telephone equipment. The outer conductor of a portion of the coaxial cable below the cellular dipole antenna serves as the AM/FM antenna. The combined antenna is encaged in a fiberglass housing and mounted on a metallic base having an upper shell and a lower shell. The upper shell is electrically connected to the outer conductor of the coaxial cable forming the antenna and the lower shell is connected to a ground plane. A coaxial cable having a center conductor connected to the upper shell and an outer conductor connected to the lower shield provides connection to AM/FM receiver equipment. Another coaxial cable having a center conductor connected to the center conductor of the antenna and an outer conductor connected to the lower shell provides connection to cellular telephone apparatus. A dielectric between the upper and lower shells provides a capacitance with low impedance in the cellular telephone frequency range and a high impedance in the AM/FM frequency range.

Signal transmitting device, circuit block and integrated circuit suited to fast signal transmission

Abstract: A signal transmitting circuit includes one or more circuit blocks having a driving circuit and an intra-block transmission line for transmitting a signal produced by the driving circuit, one or more circuit blocks having a receiving circuit and an intra-block transmission line for transmitting the signal to said receiving circuit, and a main interblock transmission line for propagating a signal between both of the driving and receiving circuit blocks. Inter-block transmission line is terminated at one or two ends by one or two resistors having substantially the same impedance as the interblock transmission line itself. Each of the intra-block transmission line is provided with a resistance element having a resistance equal to or close to a value derived by subtracting a half of an impedance of the inter-block transmission line from an impedance of the intra-block transmission line, to lower signal amplitude and suppress reflections of a signal at branch points along the main interblock transmission line, thereby enabling a high-speed signal transfer.

Analytical and experimental investigations of aperture coupled unidirectional dielectric radiator arrays (UDRA)

Abstract: Experimental and analytical investigations of unidirectional dielectric radiator arrays (UDRA) are presented for the first time. Attractive electrical performance due to the use of nonradiating dielectric waveguide (NRD) structures is demonstrated. A numerical model based on a cavity-resonator approximation is developed for prediction of radiation properties of the UDRA's. Good agreement between measurements and calculations shows the validity of the modeling approach. On the other hand, the feed technique for the UDRA by microstrip line and coupling-aperture is experimentally investigated. Measurement results show high coupling and radiation efficiencies of the proposed excitation method. Such a circuit configuration allows the combination of planar millimeter-wave M(H)MICs and NRD components in one system for the best use of different technologies.

Apparatus for transmitting electrical power and broadband communications signals through a dielectric

Abstract: An interface device permits installation of a video system by directing broadband RF signals from an outdoors transmission line to an indoors receiver and by providing electrical power from the receiver to the transmission line for the antenna electronics without requiring a hole for passage of a coaxial cable. Power transmission circuitry includes a first inductor mounted adjacent the first side of a window and connected to the first transmission line to receive DC electrical power therefrom. A square wave drive signal is applied to switch apparatus that converts the DC power received by the inductor into time-varying electrical signals that produce a time-varying magnetic field. A second inductor mounted adjacent the dielectric layer opposite the first inductor receives the transmitted power via magnetic induction. A rectifier circuit connected between the second inductor and the second transmission line converts electrical power output therefrom into DC electrical power and supplies the DC electrical power to the second transmission line. A feedback circuit maintains the frequency of the drive signal at the value for maximum power transfer. The RF signal transmission circuitry includes apparatus connected to the second transmission line to receive broadband RF signals therefrom and produce a pair of balanced feed signals. The feed signals are capacitively coupled across window glass and fed into a coaxial cable for transmission to the receiver.

Compensation for ground voltage variation on a communication bus

Abstract: A serial communication bus for a motor vehicle subject to different ground voltages on the common line and a transmitting module has a compensation circuit to prevent mismatches which distort pulse current waveforms and cause radiated emissions. When line ground voltage is higher than the transmitter voltage an integrator is used to simulate the line ground voltage and apply that to the transmitter ground. The integrator has a small current source and a very large current sink to follow the line ground potential. The transmitter output is disabled between pulses to avoid increasing the line ground voltage. When line ground voltage is lower than the transmitter voltage, the transmitter is enabled between pulses to feed current to the line to increase its potential.

Device for adjusting the beam direction of an antenna, and feed line structure therefor

Abstract: A feed line structure (1), especially integrated with a stationary array of antenna elements so as to enable adjustment of the direction of the beam radiated from the array. The feed line structure comprises a feed conductor line pattern (3) disposed on a fixed carrier plate (2) at a distance from and in parallel to a fixed ground plate (4), and a movable dielectric plate (5) located therebetween. The feed line pattern (3) is elongated in the same direction (A) as the movement direction of the dielectric plate (5). The propagation velocity of the signal components is reduced by the dielectric plate (5), whereby a controlled phase difference between the various signal components is obtained.

Planar antenna with integral impedance matching

Abstract: Planar antennas 10a, 10b require impedance matching with their associated transceivers 20a, 20b. Conventionally, an inductance coil is placed between the transceiver 20a, 20b and the antenna 10. Such coils add loss, require space within the transciever, and increase costs. This invention replaces the inductance coil with a planar transmission line 18a, 18b within the planar antenna 10a, 10b, such as a co-planar line, slotline, or microstrip line. If desired, active circuits 30 may be applied across the transmission line 18a, 18b, with an RF choke 42 being used to allow a dc bias to drive the active circuits 30 while preventing interference with RF operation.

Fuel feed for gas turbines having an annular combustion chamber

Abstract: The object of the invention is to create a simple and compact fuel feed for a gas turbine having an annular combustion chamber. In addition, the operational reliability of the gas turbine is to be improved. According to the invention, this is achieved when only one central main-gas feed line (15) and one central pilot-gas feed line (16) are connected to the annular combustion chamber (1). A main-gas ring line (13) and a pilot-gas ring line (14) are formed in the interior of the gas-turbine casing (5) or a burner hood (3) known per se. These ring lines (13, 14) are connected upstream to the main-gas feed line (15) and the pilot-gas feed line (16) respectively and downstream to the annular combustion chamber (1). (FIG. 1)

Analysis of cross-aperture coupled patch antenna using transmission line model

Abstract: A singly-fed, cross-aperture coupled microstrip antenna producing circular polarisation (CP) has been modelled using the transmission line method (TLM). The model provides an efficient technique to predict the input impedance of the structure with good accuracy when compared to measurement results.

Temp. regulating device for IC engine cooling circuit

Abstract: The device has operating elements (4,5), e.g. a thermal expansion element (4) and a bias spring (5), acting on a rotary control flap (2), switching the cooling medium from a return line (9) and a by-pass line (8) to a pump feed line (15). The operating elements are contained within a side channel (7,7') of the by-pass line, the control flap forming part of the line section between the return line and the pump feed line in one rotary position and part of the line section between the bypass line and the pump feed line in a second position. Pref. the side channel containing the operating elements is separated from the by-pass line via a cover plate (6).