Showing papers on "Feed line published in 2004"

Ultrawide-band transitions and new microwave components using double-sided parallel-strip lines

Abstract: Double-sided parallel-strip lines have been used as a balanced transmission line to feed double-sided printed antennas or to fabricate microwave components such as balanced mixers. In this paper, ultrawide-band transitions from microstrip line to double-sided parallel-strip line are developed with 1-30-GHz bandwidth. New microwave components using double-sided parallel-strip lines are designed with good measured results. The double-sided parallel-strip line has an advantage of easy realization of low-impedance lines, which are important for many component designs.

Simplified feed for modified printed Yagi antenna

Abstract: A modified printed Yagi antenna with a simplified feed mechanism is proposed. In the new design, the driver dipole is fed by a transmission line formed by two parallel strips printed on opposite sides of the dielectric substrate. This simplified feed structure results in the reduction of the transmission line length, and, consequently, the radiation losses. The analysis of the modified Yagi antenna is performed numerically using Ansoft high frequency structure simulator and is experimentally validated.

Arrangements of microstrip antennas having dielectric substrates including meta-materials

Abstract: A slot fed microstrip patch antenna (300) includes a conducting ground plane (308), the conducting ground plane (308) including at least one slot (306) A dielectric material is disposed between the ground plane (308) and at least one feed line (317), wherein at least a portion of the dielectric layer (313) includes magnetic particles (324) The dielectric layer between the feed line (317) and the ground plane (308) provides regions having high relative permittivity (313) and low relative permittivity (312) At least a portion of the stub (318) is disposed on the high relative permittivity region (313)

Radio antenna apparatus provided with controller for controlling SAR and radio communication apparatus using the same radio antenna apparatus

Abstract: A radio antenna apparatus is provided with an antenna connected with a radio communication circuit that transmits and receives a radio signal. A load impedance element is connected between a parasitic element of an electrical conductor plate and a ground of a housing of a radio communication apparatus including the radio communication circuit. A controller controls an element value of the load impedance element so as to set a current flowing on the housing to be equal to or smaller than a predetermined value when the radio communication apparatus transmits the radio signal, thereby controlling a specific absorption rate (SAR) to be equal to or smaller than a predetermined value.

Multiband planar antenna

Abstract: A multiband planar antenna intended for small-sized radio devices and a radio device. The basic structure of the antenna is a two-resonance PIFA, the radiating plane (320) of which has a structural part (321) corresponding to the lowest operating band and a structural part (322) corresponding to the upper operating band. In addition, a loop resonator (323) operating as a radiator is formed in the radiating plane. The ground conductor (325) of the feed line of the loop is at the same time the short-circuit conductor of the PIFA. The second conductor (326) of the feed line is connected to the opposite end of the loop, and it operates as the feed conductor of the PIFA. At the same time the structural part (321) of the radiating plane that corresponds to the lowest operating band is located between the loop and the structural part of the PIFA that corresponds to the upper operating band, in order to reduce the interference between them. The resonance frequency of the loop radiator is arranged on the upper operating band of the antenna, for example. Thus the loop improves the matching of the antenna on the upper operating band and the matching and efficiency on the lowest operating band as well. This is based on additional inductance caused by the loop conductor (323) that functions as a part of the feed conductor of the PIFA.

A novel wideband coplanar-fed monopole antenna

Abstract: A new T-shaped monopole antenna with a CPW feed line is presented. The theoretical analysis is based on the finite-difference time-domain (FDTD) method. The novel antenna is designed, fabricated, and then measured. The measured results, which agree with the numerical calculations very well, are given. The measured bandwidth of the antenna is approximately 116% for VSWR ≤ 2.0. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 50–52, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20372

Radio frequency antenna flexible circuit interconnect with unique micro connectors

Abstract: An RF antenna flexible circuit interconnect is disclosed with unique micro connectors. The RF antenna flexible circuit interconnect further includes a planer flexible body having an embedded RF transmission line with a first end and a second end. A first antenna micro connector is electrically coupled to the first end of the RF transmission line and a second antenna micro connector is electrically coupled to the second end of the RF transmission line. Each of the first and second antenna micro connectors include an antenna micro connector housing and an antenna central contact socket securely positioned within the antenna micro connector housing. The antenna central contact socket may also include inward bending fingers and may be designed to engage a pin that is inserted into the central contact socket.

Litzendraht loop antenna and associated methods

Abstract: The antenna includes a Litz wire loop having a plurality of individually insulated wires braided together and a plurality of splices therein to define distributed capacitors. A magnetically coupled feed loop is provided within the electrically conductive loop, and a feed structure, such as a coaxial feed line, feeds the magnetically coupled feed loop.

Transmission line phase shifter with controllable high permittivity dielectric element

Abstract: A transmission line phase shifter ideally suited for use in low-cost, steerable, phased array antennas suitable for use in wireless fidelity (WiFi) and other wireless telecommunication networks, in particular multi-hop ad hoc networks, is disclosed. The transmission line phase shifter includes a wire transmission line, such as a coaxial, stripline, microstrip, or coplanar waveguide (CPW) transmission line. A high-permittivity dielectric element that overlies the signal conductor of the wire transmission line is used to control phase shifting. Phase shifting can be electromechanically controlled by controlling the space between the high-permittivity dielectric element and the signal conductor of the wire transmission line or by electrically controlling the permittivity of the high-permittivity dielectric element.

A note on the impedance variation with feed position of a rectangular microstrip-patch antenna

Abstract: The variation with feed position of the input impedance of a rectangular patch antenna is investigated theoretically Two different feed types are examined: an inset microstrip line, and a coaxial probe The finite-difference time-domain (FDTD) technique is used for the calculations Numerical results are compared with published measurements and other theoretical models

Method and apparatus for improved plasma processing uniformity

Abstract: A method and apparatus for generating and controlling a plasma (130) formed in a capacitively coupled plasma system (100) having a plasma electrode (140) and a bias electrode in the form of a workpiece support member (170), wherein the plasma electrode is unitary and has multiple regions (Ri) defined by a plurality of RF power feed lines (156) and the RF power delivered thereto. The electrode regions may also be defined as electrode segments (420) separated by insulators (426). A set of process parameters A={n, τi, Φi, Pi, S; Li} is defined; wherein n is the number of RF feed lines connected to the electrode upper surface at locations Li, τi is the on-time of the RF power for the ith RF feed line, Φi is the phase of the ith RF feed line relative to a select one of the other RF feed lines, Pi is the RF power delivered to the electrode through the ith RF feed line at location Li, and S is the sequencing of RF power to the electrode through the RF feed lines. One or more of these parameters are adjusted so that operation of the plasma system results in a workpiece (176) being processed with a desired amount or degree of process uniformity.

Sensor system and connector used therefor

Abstract: A sensor system includes a plurality of sensor bodies arranged aligned and adjacent to each other, each of said sensor bodies being connected to an electric cord including at least a signal line via a connector. Each connector has a power feed terminal, and a detachable fitting for electrically connecting the power feed terminals of the connectors is provided between the connectors. The power supplied to the connector of any of the sensor body through the power feed line in the electric cord is distributed to the power feed terminal of another sensor body through a row of connectors. By this configuration, the number of power feed lines for the overall system can be significantly reduced, and common bodies not distinguished for the main and sub bodies can be used as the sensor bodies, whereby the cost can be reduced and inventory management can be facilitated. Further, when any of the sensor bodies fails, it is possible to simply exchange the failed sensor body only, while maintaining the use of the electric cord that has been used.

System and method for regulating antenna electrical length

Abstract: A system and method are provided for regulating the electrical length of an antenna. The method comprises: communicating transmission line signals at a predetermined frequency between a transceiver and an antenna; sensing transmission line signals; and, modifying the antenna electrical length in response to sensing the transmission line signals. Sensing transmission line signals typically means sensing transmission line signal power levels. In some aspects, the antenna impedance is modified. Alternately, it can be stated that the transmission line signal strength is optimized between the transceiver and the antenna. More specifically, communicating transmission line signals at a predetermined frequency between a transceiver and an antenna includes accepting the transmission line signal from the transceiver at an antenna port. Then, sensing transmission line signals includes measuring the transmission line signal reflected from the antenna port.

High efficiency slot fed microstrip antenna having an improved stub

Abstract: A slot fed microstrip antenna (100) having an improved stub (118) provides enhanced efficiency through more efficient coupling of electromagnetic energy between the feed line (117) and the slot (106). A dielectric layer (105) disposed between the feed line (117) and the ground plane (108) provides a first region (112) having a first relative permittivity and at least a second region (113) having a second relative permittivity. The second relative permittivity is higher as compared to the first relative permittivity. The stub (118) is disposed on the high permittivity region (113). The dielectric layer can include magnetic particles, which are preferably disposed underlying the stub.

Miniaturized ultra-wideband microstrip antenna

Abstract: A miniaturized ultra-wideband microstrip antenna, includes: a dielectric substrate; a feed line disposed on the dielectric substrate, and supplying an electromagnetic energy supplied from an external power source; a main radiating element radiating the electromagnetic energy inputted by the feed line; and at least one sub-radiating element disposed in proximity to the main radiating element for multi-radiation. Also, the antenna further includes at least one connection plate electrically connecting the main radiating element to at least one of the sub-radiating elements. The miniaturized ultra-wideband microstrip antenna can also be made ultralight, and include additional sub-radiating elements besides the main radiating element, whereby multi-radiation in UWB's range can be attained.

Analysis and experimental validation of a triaxial antenna for microwave tumor ablation

Abstract: We apply a new triaxial antenna for microwave ablation procedures. The antenna consists of a coaxial monopole inserted through an 18-gauge biopsy needle positioned one quarter-wavelength from the antenna base. The biopsy needle creates a triaxial structure, which enhances return loss by more than 10 dB, thus limiting return currents along the feed line. Numerical simulations are used to optimize the antenna design. Numerical ex vivo experimental results are presented to quantify the field distribution, heating pattern and return loss of the antenna.

Antenna and method of manufacturing the same, and portable wireless terminal using the same

Abstract: A small antenna operating in multiple modes including three or more modes. There are provided an antenna that includes a ground conductor having a ground potential, a single feeding point whose one end is formed by a part of the ground conductor, and a plurality of transmission lines to which RF power supplied to the feeding point is input, the transmission lines each radiating electromagnetic waves of three frequencies of three modes into space. These transmission lines comprises a transmission line 41 that is connected to the feeding point at one end and to a branching point at the other end, a transmission line connected between branching points, and transmission lines connected to the branching points. The lengths of the respective transmission lines are set so that impedance matching is performed at the feeding point with respect to a plurality of frequencies. The antenna is formed from an integrated metal plate.

Impedance matching for an antenna

Abstract: Radio communication terminal and a method for adaptively controlling RF power of such a radio communication terminal comprising an antenna connected to a RF power amplifier (101), comprising the steps of: detecting a forward RF signal (P F ) to and a reverse RF signal (P R ) from the antenna; detecting a phase between said forward and reverse RF signals; establishing a Voltage Standing Wave Ratio, VSWR, for the antenna; assessing a load impedance (Z L ) from the established VSWR and detected phase, and adaptively controlling the RF power dependent on the assessed load. Preferably, the step of adaptively controlling comprises the step of adjusting the impedance (Z C ) between the power amplifier and the antenna.

Wireless communication device, rf tag reader / writer and printer

Abstract: PROBLEM TO BE SOLVED: To surely communicate with only a desired RF tag when communicating with RF tags incorporated in labels successively stuck on a mounting. SOLUTION: When an antenna 7a is arranged at a distance of an integral multiple of a half of the wavelength of a radio wave reflected by a radiation element 21 of the antenna 7a from a reflecting surface of a reflecting means 9, the radio wave reflected by the antenna 7a is inverted in polarity and reflected by the reflecting means 9 and the radio wave whose polarity is inverted is received again by the antenna 7a. Consequently, the electric field intensity at a position which is at a distance of an odd multiple of a quarter of the wavelength of the radio wave reflected by the radiation element 21 of the antenna 7a from the reflecting means 9 can be increased. An area that an RF tag T passes through is set at the position which is at a distance of an odd multiple of a quarter of the wavelength of the radio wave reflected by the radiation element 21 of the antenna 7a from the reflecting means 9 to expose the passing RF tag T to a radio wave having high electric field intensity. COPYRIGHT: (C)2006,JPO&NCIPI

RF transmitter arrangement for an MR system, and method for determining a setting parameter therefor

Abstract: A radio frequency transmitter arrangement for a magnetic resonance apparatus has a distribution unit and an antenna unit, wherein the antenna unit, to generate radio frequency fields, is fashioned in at least two orthogonal modes, and the distribution unit is fashioned for the division of an RF transmission signal into at least two mode feed signals. At least one adjustment unit is provided to adjust the amplitude and/or phase of one of the mode feed signals and is connected with the antenna unit such that each of the mode feed signals generates a radio frequency field in one of the modes. A multiple transmitter arrangement has at least two radio frequency transmitter arrangements and at least two 180° hybrids. A method is provided to determine at least one setting parameter of the adjustment unit.

A new on-wafer de-embedding technique for on-chip rf transmission line interconnect characterization

Abstract: Absfracf This paper introduces a new de-embedding method for on-chip RF transmission line characterization. The new technique allows subtraction of pad parasitics based on measurements of only two LI=L and Lz=N.L (N being a discrete number) long transmission lines with attached measurement pads. No dummy “open”, “short” and “thru” devices are required. The new method has also been extended for the case when Lz#N.L, and only L,, L2 and AL= L,-L, long interconnects with attached pads are available on the test wafer. The proposed methodology has been compared with several well-known de-embedding approaches (“thru”, “open-short” aed “short-open“) and with simulation results from the industry standard electromagnetic solver (lE3D) for de-embedding of on-chip interconnects at frequencies up to 70GHz. Index Terms -Transmission Line interconnect, on-wafer measurement, S-parameters, de-embedding.

Electronically-controlled metamaterial-based transmission line as a continuous-scanning leaky-wave antenna

Abstract: An electronically-controlled metamaterial-based transmission line (TL) is demonstrated for the first time and applied to a continuous-scanning leaky-wave (LW) antenna. This transmission line is a composite right/left-handed (CRLH) microstrip structure incorporating varactor diodes for fixed-frequency voltage-controlled operation. The CRLH structure is rigorously analyzed in terms of the equivalent circuit models and dispersion diagrams. The TL behaviour is verified by way of its application as a LW antenna which is experimentally demonstrated. The antenna, operated at the fixed frequency of 3.1 GHz, exhibits the capability of continuous scanning from backward to forward angles over a range of 77/spl deg/ (from -41/spl deg/ to +36/spl deg/), with efficient broadside radiation, by varying the varactors bias voltages from 15V to 0V (5V at broadside).

Planar antenna for mobile satellite applications

Abstract: The invention relates to a microstrip patch antenna (1) for mobile satellite communications comprising a first electrically conducting ground plane (4) having at least one opening (7), at least one patch radiating element (2), at least one first dielectric layer (L2) disposed between said first electrically conducting ground plane and said patch radiating element and more particularly between said at least one opening and said patch radiating element, at least one feed line (6) for providing signal energy in a contactless manner to or from said patch radiating element through said opening and a second dielectric layer (L3) disposed between said feed line and said first electrically conducting ground plane wherein the antenna further comprises a second ground plane (8) and a third dielectric layer (L4) disposed between said second ground plane and said feed line.

Dual operational frequency slot antenna

Abstract: A dual operational frequency slot antenna for receiving/transmitting wireless signals from a satellite or for receiving/transmitting wireless signals in an RFID system comprises two L-type slot antennas and a printed circuit feed line to receive and transmit circularly polarized radiation at dual operational frequencies.

Radio lan antenna

Abstract: A high-frequency micro-strip line for transmitting a high-frequency wave for a wireless LAN system has a layered structure where, on a ground layer made of a conductive material, a dielectric layer made of a dielectric material and a signal line made of a conductive material are successively laid. The high-frequency micro-strip line further includes a patch antenna comprising a dielectric plate made of a dielectric material and a patch made of a conductive material, which are successively laid into a layered structure, the patch antenna being electrically connected to the signal line. A wireless-communication RF signal transmission device capable of being applied to such a line is also provided.

Methods and apparatus for communicating in a vehicle and other radio environments

Abstract: A transmitter device for use in a vehicular application includes a cable, an input port, a modulator, and an antenna device. The cable of the transmitter device receives power from a power source associated with a vehicle to power circuitry in the transmitter device. The input port of the transmitter device receives audio input from a user in the vehicle speaking into a microphone. The modulator device modulates the audio input received from the input port onto a carrier frequency to produce a modulated signal. The antenna device of the transmitter device receives the modulated signal and generates (e.g., transmits) a wireless radio signal to a radio receiver in the vehicle. The radio receiver in the vehicle is tuned to i) receive the wireless radio signal and ii) play the audio input received from the user over at least one corresponding speaker associated with the radio receiver.

Cryogenic cooling system and method with backup cold storage device

Abstract: A cooling system for providing cryogenic cooling fluid to a thermal load, the system comprising: a main cryogenic refrigeration system; a cryogenic cooling fluid feed line having a feed line outlet coupled to the thermal load and a feed line inlet coupled to the cryogenic refrigeration system; a cryogenic cooling fluid return line having a return line inlet coupled to the thermal load and a return line outlet coupled to the cryogenic refrigeration system; a bypass cooling system further comprising isolation valves attached to the feed line and return line wherein each of said valves has a closed position and an open position, a bypass line extending between the feed line and return line, a bypass valve and a cooling device attached to one of said feed line and return line. The bypass cooling system may further include a cold box housing the bypass line and the cooling device, e.g., an open or closed heat exchanger coupled to a storage tank of cryogen.

Slot coupling patch antenna

Abstract: An antenna for receiving and/or transmitting circularly and/or linearly polarized RF signals includes a radiation element, a ground plane, a dielectric substrate, and a feed line. The radiation element is disposed on a pane of glass. The radiation element defines a slot having a first leg and a second leg forming the shape of a cross for generating the circular and/or linear polarization. The cross-shaped slot includes a center point. The ground plane is disposed substantially parallel to and spaced from the radiation element. The dielectric substrate is sandwiched between the radiation element and the ground plane. The feed line extends within the dielectric substrate and is electromagnetically coupled with the radiation element and the ground plane. The feed line terminates at a distal end short of the center point of the slot. That is, the feed line does not cross the center point. The antenna is compact in size and generally conformal to the pane of glass.

Transmission line with low dispersive properties and its application in equalization

Abstract: A transmission line is provided with added shunt resistance, R SH , distributed along the length of the micro transmission line permitting the extension of constant characteristic impedance to the transmission line to lower signal frequencies. The loss in gain to the signal propagating the transmission line due to the added resistance can be compensated for by amplification provided at the output of the transmission line or at output taps provided along the length of the transmission line such as in cases where the line is utilized as a circuit delay line. An exemplified application disclosed is an analog delay line formed as a metal microstrip in an IC chip circuit provided, for example, in a feed forward equalizer (FFE).

Antenna selection with RF pre-processing: robustness to RF and selection non-idealities

Abstract: Multiple antenna transmitter and receiver architectures that combine antenna selection with RF pre-processing have been shown to significantly outperform conventional antenna selection with the same number of RF chains Often, performance close to a full complexity architecture (with more RF chains) is also achieved This work studies the effect of hardware and signal processing non-idealities on such architectures We show that they are robust to quantization, phase, and calibration errors introduced by RF phase-shifters, and also to the channel estimation errors While insertion loss does lead to performance degradation, performance better than conventional antenna selection is observed for typical insertion loss values