WO2004057697A2 - Antenne a commutation de frequence rapide - Google Patents

Antenne a commutation de frequence rapide Download PDF

Info

Publication number
WO2004057697A2
WO2004057697A2 PCT/IL2003/001061 IL0301061W WO2004057697A2 WO 2004057697 A2 WO2004057697 A2 WO 2004057697A2 IL 0301061 W IL0301061 W IL 0301061W WO 2004057697 A2 WO2004057697 A2 WO 2004057697A2
Authority
WO
WIPO (PCT)
Prior art keywords
antenna
switch
transmit
impedance elements
time slots
Prior art date
Application number
PCT/IL2003/001061
Other languages
English (en)
Other versions
WO2004057697A3 (fr
Inventor
Asher Peled
Ehud Heyman
Ben-Zion Steinberg
Rafael Kastner
Amir Boag
Original Assignee
Xellant Mop Israel Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xellant Mop Israel Ltd. filed Critical Xellant Mop Israel Ltd.
Priority to AU2003285741A priority Critical patent/AU2003285741A1/en
Publication of WO2004057697A2 publication Critical patent/WO2004057697A2/fr
Publication of WO2004057697A3 publication Critical patent/WO2004057697A3/fr

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/06—Details
    • H01Q9/14—Length of element or elements adjustable

Definitions

  • the present invention relates generally to antennas, and specifically to antennas whose frequency response can be switched over multiple bands.
  • Tunable antennas are known in the art.
  • U.S. Patent 6,614,399 whose disclosure is incorporated herein by reference, describes a multi-band compact tunable directional antenna for wireless communication devices.
  • the antenna provides resonance over at least two frequency bands with a directional radiation pattern and reduced specific absorption rate (SAR) .
  • the antenna structure includes a conducting plate resonator, which is spaced from a larger, rectangular ground plane conductor. The size and shape of the resonator and ground plane are compatible with the dimensions of wireless communications devices such as cell phones.
  • the antenna structure described in U.S. Patent 6,614,399 includes two or more tuning capacitors, which cause the resonator to resonate over two or more frequency ranges.
  • the capacitors can be made variable by techniques such as switched fixed capacitors, which are selected by PIN diodes, or by using voltage-controlled capacitors ( "varactors") . In either case, the capacitance value may be controlled electrically or by a digital command signal.
  • variable capacitors is said to facilitate seamless roaming across cellular service regions having different frequency allocations for particular bands.
  • U.S. Patent 6,255,994 whose disclosure is incorporated herein by reference, describes an inverted-F antenna, which is capable of coping with changes in available frequency bands.
  • the antenna comprises a radiating element and a ground conductor, which is arranged to be opposite to the radiating element with a specific gap.
  • a feeding terminal and a grounding terminal are electrically connected to the radiating element.
  • At least one impedance element (an inductance or capacitance) is provided in a line connecting the grounding terminal to the ground conductor.
  • a switch is used for selectively inserting the impedance element into the line. The resonant frequency of the antenna is changed by operating the switch.
  • Embodiments of the present invention provide improved methods and devices for switching the resonant frequency of an antenna.
  • a tuning circuit which comprises a network of impedance elements, such as lumped capacitors and inductors, is arranged to load the antenna.
  • One or more switches are coupled to engage or disengage selected impedance elements from the antenna. Each different setting of the switches changes the configuration of the impedance elements loading the antenna, and thus varies the resonant frequency of the antenna.
  • the impedance elements are arranged so that the antenna resonates in two different bands, and so that changing the setting of the switches tunes the frequencies of both resonant bands simultaneously.
  • the switches that are used for frequency tuning comprise field effect transistors (FETs) .
  • FETs field effect transistors
  • These switches consume very low power, in contrast to the PIN diodes and varactors that are used in tunable antennas known in the art. Therefore, antenna assemblies produced in accordance with these embodiments are useful particularly (although not exclusively) in handheld, battery-powered mobile communication devices, such as cellular handsets and wireless computing devices.
  • a novel voltage divider circuit is provided in order to prevent radio frequency (RF) voltage overload of the switches during transmission.
  • the antenna frequency may be switched as necessary between different sub-bands within the total bandwidth.
  • the antenna may be switched between the frequencies of different cells in a cellular network or different channels in a wireless local area network (WLAN) .
  • WLAN wireless local area network
  • the communication device to which the antenna is coupled transmits and receives signals in different time slots, it is even possible to switch the antenna between the transmit and receive bands in the appropriate time slots.
  • the use of a narrowband, high-gain antenna in this manner reduces the power consumption of the communication device and enhances signal quality. This approach also relaxes the design constraints on the antenna itself, since it is often difficult to achieve high bandwidth in the types of small antennas that are typically used in mobile communication devices, such as cellular telephones .
  • an antenna assembly for a communication device including: an antenna; and a tuning circuit, including: a network of impedance elements, which are coupled to load the antenna with a complex impedance such that the antenna assembly has first and second resonant frequencies in distinct first and second bands; and at least one switch, which is coupled to switch a configuration of the impedance elements so as to vary the impedance of the network, thus tuning the first and second resonant frequencies simultaneously.
  • the at least one switch includes a field-effect transistor (FET)
  • the impedance elements include one or more capacitors and one or more inductors.
  • the network includes a resonant LC circuit, including at least a first one of the capacitors and at least one of the inductors, which is coupled in a series connection with at least a second one of the capacitors.
  • the at least one switch may be coupled to switch the second one of the capacitors into and out of the series connection.
  • the series connection includes the second one of the capacitors and a third one of the capacitors, which is arranged in series with the second one of the capacitors, and the at least one switch is coupled to the network at a point intermediate the second one and the third one of the capacitors.
  • the resonant LC circuit is coupled in the series connection with the second one of the capacitors and with at least a third one of the capacitors, which is arranged in parallel with the second one of the capacitors, and the at least one switch includes at least first and second switches, which are coupled respectively to switch the second one and the third one of the capacitors into and out of the series connection.
  • the antenna includes a surface having a slot opening therethrough, and at least one of the impedance elements is disposed across the slot.
  • the surface has at least first and second slots opening therethrough, and the impedance elements include at least a first impedance element that is disposed across the first slot, and at least a second impedance element that is disposed across the second slot, wherein the first and second impedance elements are coupled to one another in series.
  • the surface having the slot opening therethrough is a first surface of the antenna, and the antenna further includes a second surface, spaced from the first surface so as to define a cavity therebetween, wherein the slot opens into the cavity.
  • the impedance elements include at least first and second impedance elements, which are arranged in series, and the at least one switch is coupled to the network at a point intermediate the first and second impedance elements.
  • the first resonant frequency is in a band between about 800 and 1000 MHz
  • the second resonant frequency is in a band between about 1700 and 1900 MHz.
  • an antenna assembly for a communication device including: an antenna; and a tuning circuit, including: a network of impedance elements, which are coupled to load the antenna with an impedance, which determines a resonant frequency of the antenna assembly, the network including at least first and second impedance elements arranged in series; and a switch, which is coupled to the network at a point intermediate the first and second impedance elements, and which is operative to switch a configuration of the impedance elements so as to vary the impedance of the network, thus tuning the resonant frequency.
  • the first and second impedance elements are configured to operate as a radio frequency (RF) voltage divider, so as to prevent a RF voltage overload on the switch while the communication device is transmitting a signal via the antenna.
  • RF radio frequency
  • the first and second impedance elements include first and second capacitors
  • the switch is configured to couple the second capacitor into and out of the series with the first capacitor.
  • the communication device is configured to transmit and receive signals via the antenna assembly in respective transmit and receive time slots at different transmit and receive frequencies
  • the switch is operative to switch the configuration of the impedance elements so as to tune the resonant frequency between the transmit and receive frequencies
  • the assembly further includes a controller, which is adapted to actuate the switch in synchronization with the time slots, so that the resonant frequency corresponds to the transmit frequency during the transmit time slots and to the receive frequency during the receive time slots.
  • the switch is operative to ground the point intermediate the first and second impedance elements during the receive time slots and to decouple the point from ground during at least some of the transmit time slots.
  • an antenna assembly for a communication device, which is configured to transmit and receive signals in respective transmit and receive time slots at different transmit and receive frequencies, the assembly including: an antenna; a tuning circuit, including: a network of impedance elements, which are coupled to load the antenna with an impedance, which determines a resonant frequency of the antenna; and at least one switch, which is coupled to alter a configuration of the impedance elements so as to vary the impedance, in order to tune the resonant frequency between the transmit and receive frequencies; and a controller, which is adapted to actuate the at least one switch in synchronization with the time slots, so that the resonant frequency corresponds to the transmit frequency during the transmit time slots and to the receive frequency during the receive time slots.
  • a method for tuning an antenna assembly including: coupling a network of impedance elements to load an antenna with a complex impedance such that the antenna assembly has first and second resonant frequencies in distinct first and second bands; and switching a configuration of the impedance elements so as to vary the impedance of the network, thus tuning the first and second resonant frequencies simultaneously.
  • a method for tuning an antenna assembly including: coupling a network of impedance elements to load an antenna with an impedance, which determines a resonant frequency of the antenna assembly, the network including at least first and second impedance elements arranged in series; coupling a switch to the network at a point intermediate the first and second impedance elements; and actuating the switch so as to vary the impedance of the network, thus tuning the resonant frequency.
  • a method for wireless communication including: configuring a communication device to transmit and receive signals via an antenna in respective transmit and receive time slots at different transmit and receive frequencies; coupling a network of impedance elements to load the antenna with an impedance, which determines a resonant frequency of the antenna; and switching a configuration of the impedance elements so as to vary the impedance, in order to tune the resonant frequency between the transmit and receive frequencies in synchronization with the time slots, so that the resonant frequency corresponds to the transmit frequency during the transmit time slots and to the receive frequency during the receive time slots.
  • FIG. 1A is a schematic, pictorial illustration of a dual- band antenna assembly with switchable resonant frequencies, in accordance with an embodiment of the present invention
  • Fig. IB is a schematic side view of the antenna assembly of Fig. 1A;
  • Fig. 2 is a schematic frontal view of a tuning circuit used in a dual-band antenna assembly, in accordance with an embodiment of the present invention;
  • Fig. 3 is an electrical schematic diagram showing elements of an antenna tuning circuit, in accordance with an embodiment of the present invention.
  • Figs. 4A and 4B are schematic plots of the predicted reflection coefficient of a switchable antenna assembly as a function of frequency for different settings of a tuning circuit used in the antenna assembly, in accordance with an embodiment of the present invention.
  • Figs. 5A and 5B are schematic plots of the measured reflection coefficient of a switchable antenna assembly as a function of frequency for different settings of a tuning circuit used in the antenna assembly, in accordance with an embodiment of the present invention.
  • Figs. 1A and IB schematically illustrate an antenna assembly 20, in accordance with an embodiment of the present invention.
  • Fig. 1A is a pictorial view, showing the antenna assembly mounted on a communication device 21, while Fig. IB presents a side view.
  • Device 21 typically comprises a cellular handset or, alternatively, a wireless computing device, such as a personal digital assistant (PDA) with communication capability or a WLAN transceiver embedded in a computer.
  • PDA personal digital assistant
  • WLAN transceiver embedded in a computer.
  • the principles of the present invention may be used in communication devices of other types, as well.
  • Assembly 20 comprises an antenna 22, which may protrude outside communication device 21, as shown in the figures, or may be mounted inside the case of the communication device.
  • antenna 22 is a cavity antenna, having a front conductive surface 24 and a rear conductive surface 26, which define a cavity therebetween.
  • antenna 22 is about 40 mm wide by 20 mm high, with a separation of about 5 mm between the front and rear surfaces. Alternatively, larger or smaller dimensions may be used.
  • a RF feed 28, surrounded by a coaxial shield 30, couples front surface 24 to a transceiver circuit (not shown) in device 21.
  • a switched tuning circuit 32 is connected in series between front surface 24 and ground. The tuning circuit is described in detail hereinbelow.
  • antennas of other types may be tuned using the approach embodied in assembly 20.
  • antenna 22 may comprise an inverted F or planar inverted F antenna.
  • suitable antenna types for this sort of switched tuning include meander antennas, slot antennas, monopole and dipole antennas, and microstrip antennas (including patch antennas) . Modification required in each of these antenna designs to accommodate tuning circuit 32 will be apparent to those skilled in the art upon reading the present disclosure.
  • Fig. 2 is a schematic, frontal view of tuning circuit 32, in accordance with an embodiment of the present invention.
  • Circuit 32 comprises a network of inductors and capacitors, coupled across two slots that open into the cavity of assembly
  • C2 series capacitor 52
  • Units 47 and 48 each comprise only series capacitor 42 (C3) and FET 56.
  • Each FET 56 is actuated (opened or closed) by changing the bias voltage that is applied to the gate (G) of the FET.
  • the gate When the gate is unbiased, the FET is switched on, so that its source and drain are galvanically engaged in an effective short circuit.
  • a suitable bias typically +5 volts, is applied to the gate, the FET is switched off, so that there is effectively an open circuit between the source and drain.
  • the state of FETs 56 determines the capacitance of each of units 45, 46, 47 and 48, and thus determines the overall capacitance Op of the portion of circuit 32 that is coupled across lower slot 38.
  • Table I below presents this impedance for a set of different states of the FETs:
  • the total load impedance Zj_, of circuit 32 is obtained by
  • LI and C ⁇ are the total inductance and capacitance of the parallel inductors 42 and capacitors 44 in the upper portion of the circuit, and ⁇ is the frequency in rad/sec.
  • the resonant frequencies of antenna assembly 20 are given by the roots CUQ of the following resonance condition:
  • Z ⁇ is the wave impedance of the metallic body of antenna
  • equation (1) the resonant frequencies CDQ of the antenna assembly.
  • equation (2) has two roots, so that assembly 20 has two resonant frequencies.
  • these frequencies can be made to fall in two distinct operating bands of communication device 21.
  • one of the resonant frequencies can be set in the GSM band (880-900 MHz) , while the other is in the GPRS band (1710-1880 MHz) .
  • GSM band 880-900 MHz
  • GPRS band GPRS band
  • Fig. 3 is a schematic electrical diagram showing details of units 45 and 46 in tuning circuit 32, in accordance with an embodiment of the present invention.
  • a bias voltage supply 60 is connected to the gate of FET 56 through resistors 62 and 64.
  • a tuning control circuit 68 comprises a switch 66, which turns off the gate bias when closed. Similar switches are provided to control the other FETs in circuit 32. Alternatively, other means, as are known in the art, may be used by the control circuit to actuate FETs 56.
  • Control circuit 68 is typically contained in communication device 21, and is operative to turn the gate bias to each of FETs 56 on and off selectively in order to set the state of tuning circuit 32.
  • control circuit 68 sets switches 66 according to the sub-band on which device 21 is to communicate, and changes the settings when the sub-band selection is to change.
  • a change in the switch settings generally changes the sub-band selection simultaneously in both the upper and lower operating bands served by antenna assembly 20.
  • communication device 21 transmits signals in one frequency band and receives signals in another. Furthermore, the communication device transmits and receives signals only in certain time slots. Assuming the transmit and receive time slots do not overlap, control circuit 68 may toggle FETs 56 rapidly, in synchronization ' with the time slots, so that assembly 20 is tuned to the assigned transmit sub-band during transmit slots and to the assigned receive sub-band during receive slots. This rapid band switching will work even when communicating in full duplex mode, since the data transmitted and received by device 21 are typically compressed so that continuous voice data can be transmitted and received within the assigned time slots.
  • tuning circuit 32 may be designed so that one of the resonant frequencies of antenna assembly 20 is in the transmit band, and the other resonant frequency is in the receive band.
  • FETs 56 may be operated to switch both the transmit and receive sub-bands to the proper settings simultaneously.
  • capacitors 52 and 54 in series across slot 38 serves as a RF voltage divider when FET 56 is switched off (and thus behaves as an open circuit) .
  • the reason for this arrangement is that the RF voltage that develops over slot 38 during transmission, in small antennas such as antenna 22, is typically higher than the total voltage that the FET can sustain in the off position. (This sort of phenomenon is sometimes referred to as RF voltage overflow.)
  • the series arrangement of capacitors 52 and 54 reduces the voltage across FET 56 when the FET is turned off. This voltage reduction circuitry is not needed when the FET is turned on (short circuit) . In the specific design of circuit 32 that is shown in Fig.
  • the choice of transmit and receive frequencies is such that only the FETs in switched impedance units 45 and 46 are ever turned off during transmission.
  • the FETs in units 47 and 48 are always on during transmission, and are turned off in order to select receive bands. Therefore, there is no need for a voltage divider to protect the FETs in units 47 and 48.
  • the voltage divider arrangement may be applied to other FETs, or to all of the FETs (or none of the FETs) , as required.
  • Figs. 4A and 4B are schematic plots of the predicted reflection coefficients Sn of antenna assembly 20, when the antenna assembly is fed by a 50 ⁇ coaxial cable, in accordance with an embodiment of the present invention.
  • Curves 70, 72, 74, 76 and 78 show the reflection coefficients in the lower (900 MHz) band
  • curves 80, 82, 84, 86 and 88 show the reflection coefficients in the upper (1700-1800 MHz) band.
  • These curves correspond respectively to states #1 through #5 of tuning circuit 32 that are shown above in Table I, and correspond to the resonant sub-bands of assembly 20 in each state.
  • the curves were calculated based on the antenna dimensions given above and the following values of the circuit components:
  • FIGs. 5A and 5B are schematic plots of actual, measured reflection coefficients of another antenna assembly (not shown in the figures) , which was constructed in accordance with an alternative embodiment of the present invention, and was fed by a 50 ⁇ coaxial cable.
  • the antenna in this embodiment was similar to antenna 22, as described above, while the tuning circuit had eight switched impedance units across slot 38, created by duplicating each of units 45, 46, 47 and 48. Switching off the FET in each of these units in turn, in a manner similar to that illustrated in Table I above, gives nine different states of the tuning circuit. Accordingly, Figs. 5A and 5B each show nine different sub-bands served by the antenna assembly in the lower and upper bands, respectively.
  • tuning circuits may be designed to cause the antenna assembly in which they are used to have two simultaneous, switchable resonant frequencies, as in the embodiments described above, or to have more than two switchable resonant frequencies, or only a single resonant frequency.
  • the resonant frequencies may be in the cellular service range, as shown in Figs. 4A/B and 5A/B, or they may alternatively be at lower frequencies or at higher, multi- gigahertz frequencies.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Transceivers (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Details Of Aerials (AREA)
  • Waveguide Aerials (AREA)

Abstract

L'invention concerne un ensemble antenne (20) destiné à un dispositif de communication (21) et comprenant une antenne (22) et un circuit d'accord (32). Le circuit d'accord comprend un réseau d'éléments d'impédance (42, 44, 52, 54) couplés de façon à charger l'antenne avec une impédance complexe, l'ensemble antenne présentant ainsi des première et seconde fréquences de résonance dans des première et seconde bande de fréquence distinctes. Au moins un commutateur (56) est couplé pour le changement d'une configuration des éléments d'impédance en vue d'une variation de l'impédance du réseau, ce qui permet d'accorder lesdites première et seconde fréquences de résonance simultanément.
PCT/IL2003/001061 2002-12-19 2003-12-11 Antenne a commutation de frequence rapide WO2004057697A2 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2003285741A AU2003285741A1 (en) 2002-12-19 2003-12-11 Antenna with rapid frequency switching

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US43458202P 2002-12-19 2002-12-19
US60/434,582 2002-12-19

Publications (2)

Publication Number Publication Date
WO2004057697A2 true WO2004057697A2 (fr) 2004-07-08
WO2004057697A3 WO2004057697A3 (fr) 2004-09-10

Family

ID=32682072

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IL2003/001061 WO2004057697A2 (fr) 2002-12-19 2003-12-11 Antenne a commutation de frequence rapide

Country Status (2)

Country Link
AU (1) AU2003285741A1 (fr)
WO (1) WO2004057697A2 (fr)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007042615A1 (fr) * 2005-10-14 2007-04-19 Pulse Finland Oy Antenne ajustable
US7889143B2 (en) 2005-10-03 2011-02-15 Pulse Finland Oy Multiband antenna system and methods
US9509054B2 (en) 2012-04-04 2016-11-29 Pulse Finland Oy Compact polarized antenna and methods
US9634383B2 (en) 2013-06-26 2017-04-25 Pulse Finland Oy Galvanically separated non-interacting antenna sector apparatus and methods
US9647338B2 (en) 2013-03-11 2017-05-09 Pulse Finland Oy Coupled antenna structure and methods
US9673507B2 (en) 2011-02-11 2017-06-06 Pulse Finland Oy Chassis-excited antenna apparatus and methods
US9680212B2 (en) 2013-11-20 2017-06-13 Pulse Finland Oy Capacitive grounding methods and apparatus for mobile devices
US9722308B2 (en) 2014-08-28 2017-08-01 Pulse Finland Oy Low passive intermodulation distributed antenna system for multiple-input multiple-output systems and methods of use
US9761951B2 (en) 2009-11-03 2017-09-12 Pulse Finland Oy Adjustable antenna apparatus and methods
US9906260B2 (en) 2015-07-30 2018-02-27 Pulse Finland Oy Sensor-based closed loop antenna swapping apparatus and methods
US9917346B2 (en) 2011-02-11 2018-03-13 Pulse Finland Oy Chassis-excited antenna apparatus and methods
US9948002B2 (en) 2014-08-26 2018-04-17 Pulse Finland Oy Antenna apparatus with an integrated proximity sensor and methods
US9973228B2 (en) 2014-08-26 2018-05-15 Pulse Finland Oy Antenna apparatus with an integrated proximity sensor and methods
US9979078B2 (en) 2012-10-25 2018-05-22 Pulse Finland Oy Modular cell antenna apparatus and methods
US10069209B2 (en) 2012-11-06 2018-09-04 Pulse Finland Oy Capacitively coupled antenna apparatus and methods
US10079428B2 (en) 2013-03-11 2018-09-18 Pulse Finland Oy Coupled antenna structure and methods

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI20096251A0 (sv) 2009-11-27 2009-11-27 Pulse Finland Oy MIMO-antenn
US8847833B2 (en) 2009-12-29 2014-09-30 Pulse Finland Oy Loop resonator apparatus and methods for enhanced field control
FI20105158A (fi) 2010-02-18 2011-08-19 Pulse Finland Oy Kuorisäteilijällä varustettu antenni
US9406998B2 (en) 2010-04-21 2016-08-02 Pulse Finland Oy Distributed multiband antenna and methods
FI20115072A0 (fi) 2011-01-25 2011-01-25 Pulse Finland Oy Moniresonanssiantenni, -antennimoduuli ja radiolaite
US8866689B2 (en) 2011-07-07 2014-10-21 Pulse Finland Oy Multi-band antenna and methods for long term evolution wireless system
US9450291B2 (en) 2011-07-25 2016-09-20 Pulse Finland Oy Multiband slot loop antenna apparatus and methods
US9123990B2 (en) 2011-10-07 2015-09-01 Pulse Finland Oy Multi-feed antenna apparatus and methods
US9531058B2 (en) 2011-12-20 2016-12-27 Pulse Finland Oy Loosely-coupled radio antenna apparatus and methods
US9484619B2 (en) 2011-12-21 2016-11-01 Pulse Finland Oy Switchable diversity antenna apparatus and methods
US9590308B2 (en) 2013-12-03 2017-03-07 Pulse Electronics, Inc. Reduced surface area antenna apparatus and mobile communications devices incorporating the same
US9350081B2 (en) 2014-01-14 2016-05-24 Pulse Finland Oy Switchable multi-radiator high band antenna apparatus

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5483158A (en) * 1993-10-21 1996-01-09 The Regents Of The University Of California Method and apparatus for tuning MRI RF coils

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5483158A (en) * 1993-10-21 1996-01-09 The Regents Of The University Of California Method and apparatus for tuning MRI RF coils

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7889143B2 (en) 2005-10-03 2011-02-15 Pulse Finland Oy Multiband antenna system and methods
WO2007042615A1 (fr) * 2005-10-14 2007-04-19 Pulse Finland Oy Antenne ajustable
US9761951B2 (en) 2009-11-03 2017-09-12 Pulse Finland Oy Adjustable antenna apparatus and methods
US9673507B2 (en) 2011-02-11 2017-06-06 Pulse Finland Oy Chassis-excited antenna apparatus and methods
US9917346B2 (en) 2011-02-11 2018-03-13 Pulse Finland Oy Chassis-excited antenna apparatus and methods
US9509054B2 (en) 2012-04-04 2016-11-29 Pulse Finland Oy Compact polarized antenna and methods
US9979078B2 (en) 2012-10-25 2018-05-22 Pulse Finland Oy Modular cell antenna apparatus and methods
US10069209B2 (en) 2012-11-06 2018-09-04 Pulse Finland Oy Capacitively coupled antenna apparatus and methods
US9647338B2 (en) 2013-03-11 2017-05-09 Pulse Finland Oy Coupled antenna structure and methods
US10079428B2 (en) 2013-03-11 2018-09-18 Pulse Finland Oy Coupled antenna structure and methods
US9634383B2 (en) 2013-06-26 2017-04-25 Pulse Finland Oy Galvanically separated non-interacting antenna sector apparatus and methods
US9680212B2 (en) 2013-11-20 2017-06-13 Pulse Finland Oy Capacitive grounding methods and apparatus for mobile devices
US9948002B2 (en) 2014-08-26 2018-04-17 Pulse Finland Oy Antenna apparatus with an integrated proximity sensor and methods
US9973228B2 (en) 2014-08-26 2018-05-15 Pulse Finland Oy Antenna apparatus with an integrated proximity sensor and methods
US9722308B2 (en) 2014-08-28 2017-08-01 Pulse Finland Oy Low passive intermodulation distributed antenna system for multiple-input multiple-output systems and methods of use
US9906260B2 (en) 2015-07-30 2018-02-27 Pulse Finland Oy Sensor-based closed loop antenna swapping apparatus and methods

Also Published As

Publication number Publication date
WO2004057697A3 (fr) 2004-09-10
AU2003285741A8 (en) 2004-07-14
AU2003285741A1 (en) 2004-07-14

Similar Documents

Publication Publication Date Title
WO2004057697A2 (fr) Antenne a commutation de frequence rapide
KR100993439B1 (ko) 안테나 장치 및 무선 통신 장치
US6650295B2 (en) Tunable antenna for wireless communication terminals
KR100906510B1 (ko) 안테나 장치
US6765536B2 (en) Antenna with variably tuned parasitic element
US7482991B2 (en) Multi-band compact PIFA antenna with meandered slot(s)
US6515625B1 (en) Antenna
EP1790034B1 (fr) Antenne et dispositif portable de radiocommunications la contenant
CN109193153B (zh) 天线系统、方法以及移动通信装置
Panayi et al. Tuning techniques for the planar inverted-F antenna
US20020183013A1 (en) Programmable radio frequency sub-system with integrated antennas and filters and wireless communication device using same
US20060281423A1 (en) Methods and Apparatuses for Adaptively Controlling Antenna Parameters to Enhance Efficiency and Maintain Antenna Size Compactness
CN101809813A (zh) 可调节多频带天线
CN1954460A (zh) 包括多个独立的低频带频率天线的多频带天线系统、无线终端和包含它们的无线电话
KR20070051292A (ko) 안테나 장치 및 그러한 안테나 장치를 포함하는 휴대무선통신 장치
CN101507046A (zh) 多部分无线设备
US7928914B2 (en) Multi-frequency conductive-strip antenna system
WO2015011468A1 (fr) Antennes multibandes utilisant des boucles ou des encoches
Sheta et al. Compact dual-band tunable microstrip antenna for GSM/DCS-1800 applications
KR19990072994A (ko) 다수의주파수대역에서동작되도록적용되는안테나
EP1364428B1 (fr) Terminal sans fil
Ni Tunable dual-band IFA antenna using LC resonators

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): BW GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established
122 Ep: pct application non-entry in european phase
32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 69(1) EPC

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase in:

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP