EP2087551A1 - Multi resonant antenna - Google Patents

Multi resonant antenna

Info

Publication number
EP2087551A1
EP2087551A1 EP07833611A EP07833611A EP2087551A1 EP 2087551 A1 EP2087551 A1 EP 2087551A1 EP 07833611 A EP07833611 A EP 07833611A EP 07833611 A EP07833611 A EP 07833611A EP 2087551 A1 EP2087551 A1 EP 2087551A1
Authority
EP
European Patent Office
Prior art keywords
antenna
parasitic device
antenna element
parasitic
resonant frequency
Prior art date
Legal status (The legal status 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 status listed.)
Ceased
Application number
EP07833611A
Other languages
German (de)
French (fr)
Other versions
EP2087551A4 (en
Inventor
Je-Hoon Yun
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electronics and Telecommunications Research Institute ETRI
Original Assignee
Electronics and Telecommunications Research Institute ETRI
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 Electronics and Telecommunications Research Institute ETRI filed Critical Electronics and Telecommunications Research Institute ETRI
Publication of EP2087551A1 publication Critical patent/EP2087551A1/en
Publication of EP2087551A4 publication Critical patent/EP2087551A4/en
Ceased legal-status Critical Current

Links

Classifications

    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
    • 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
    • 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
    • H01Q1/243—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 with built-in antennas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/24—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
    • H01Q5/30—Arrangements for providing operation on different wavebands
    • H01Q5/307—Individual or coupled radiating elements, each element being fed in an unspecified way
    • H01Q5/342—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes
    • H01Q5/357—Individual or coupled radiating elements, each element being fed in an unspecified way for different propagation modes using a single feed point
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
    • H01Q5/30—Arrangements for providing operation on different wavebands
    • H01Q5/378—Combination of fed elements with parasitic elements
    • 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
    • H01Q9/145—Length of element or elements adjustable by varying the electrical length
    • 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
    • H01Q9/30—Resonant antennas with feed to end of elongated active element, e.g. unipole
    • H01Q9/42—Resonant antennas with feed to end of elongated active element, e.g. unipole with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Definitions

  • the present invention relates to a small multi- resonant antenna; and, more particularly, to a small multi-resonant antenna having a wideband characteristic and capable of widely varying resonant frequencies and delicately adjusting frequency within a randomly selected resonant frequency.
  • antennas In general, antennas have narrowband characteristics and when they are miniaturized, their antenna radiation patterns have omni-directional characteristics and their antenna gains decrease. Also, input resistance of an antenna becomes very small and reactance becomes very high. Thus, the bandwidth of the antenna becomes narrow.
  • T-DMB Terrestrial Digital Multimedia Broadcasting
  • DVD-H Digital Video Broadcasting-Handheld
  • S- DMB Satellite Digital Multimedia Broadcasting
  • DAB Digital Audio Broadcasting
  • the frequency bands used in the services belong to low frequency bands, whose wavelength is longer than the length of a mobile phone.
  • a conventional 1/4 wavelength monopole antenna (for example, the wavelength of T-DMB is about 40cm) is longer than a mobile phone. Thus, it is inconvenient to use the antenna and the antenna can be hardly embedded inside a mobile phone.
  • antenna efficiency is a ratio between power radiated from an antenna and power supplied to the antenna.
  • the audio, video and broadcasting services have a problem that radio frequency (RF) signals have too wide frequency band to be covered with one small antenna.
  • RF radio frequency
  • small antennas since small antennas have limited maximal bandwidth, a single small antenna cannot afford receiving RF signals of entire bandwidths.
  • the maximal bandwidth that a 1/25 wavelength small antenna can acquire while maintaining fine antenna efficiency lies within about 3% around center frequency.
  • the bandwidth of T- DMB (which ranges from 174MHz to 216MHz) occupies about 22% around the center frequency. Therefore, one antenna cannot accommodate the frequency bandwidth.
  • CDMA Code Division Multiple Access
  • GSM Global System for Mobile Telecommunication
  • PCS Personal Communication Services
  • RFID Radio Frequency Identification
  • a reception function of an FM radio broadcasting service Bluetooth service and so forth.
  • an antenna capable of transmitting/receiving signals in multiple bands is required.
  • Fig. 1 shows T-DMB frequency bandwidth and channel bandwidth that are used currently.
  • the T-DMB frequency bandwidth includes a plurality of channel bandwidths .
  • the T-DMB frequency bandwidth is 42 MHz, one channel bandwidth is very narrow, i.e., 1.536MHz.
  • the channel bandwidth of another channel is not used. Therefore, it is possible for one small antenna to receive signals of wideband by switching channels .
  • Fig. 2 is a view showing a typical small antenna employing a parasitic device.
  • the small antenna employing a parasitic device controls resonant frequency by using a varactor diode and varying capacitance to change inductance or capacitance.
  • the small antenna employing a parasitic device includes a conductor 201, a circuit output unit 203, a parasitic device 205, a parasitic device switch 207, and a Printed Circuit Board (PCB) edge plane (not shown) .
  • the PCB edge plane includes a circuit generally realized in antennas and a ground line.
  • the conductor 201 is an antenna element. It transmits or receives signals to or from the outside.
  • the circuit output unit 203 supplies power from the PCB edge plane (not shown) to the conductor 201.
  • a varactor diode or a varying capacitance may be used as for the parasitic device 205.
  • the parasitic device switch 207 connects the parasitic device 205 to a ground plane included in the PCB edge plane (not shown) based on a control signal under the control of the PCB edge plane (not shown) .
  • the parasitic device 205 is connected to or disconnected from the antenna circuit upon on/off of the parasitic device switch 207.
  • the varactor diode or the varying capacitance sensitively reacts with a surrounding environment (such as static electricity caused by hand or hair), and devices such as varactor diodes which require bias voltage supplied regularly for each product can hardly maintain a predetermined capacitance value. Therefore, it is hard to generate resonant frequency of a predetermined level.
  • the reactance value varies so much that the resonant frequencies cannot be delicately adjusted to include all channels for T-DMB, S-DMB, DVB-H and D-TV. Furthermore, since the reactance value of the parasitic device is synthetically determined based on the aperture, shape and position of the parasitic device, capacitance, and inductance, it is difficult to predict the variance of the resonant frequency.
  • Fig. 3 is a graph showing an SIl parameter according to on/off of the parasitic device switch in the small antenna of Fig. 2.
  • the antenna is a disconnected line.
  • the ends of the antenna resonate in predetermined frequency.
  • signals are not totally reflected and they are delivered to the outside as a specific electromagnetic energy.
  • an antenna is basically a one-port device whose input port is one.
  • the antenna has only an SlI value which signifies an input reflection coefficient, and the antenna has the minimal SlI value (dB) in operation frequency.
  • the frequency where the SlI value is the minimum signal power inputted to the antenna is radiated maximally. In other words, impedance is best matched at a point where the SIl value is the minimum.
  • a graph shows a case when the parasitic device switch is turned off
  • B graph shows a case when the parasitic device switch is turned on.
  • Both A and B graphs include a first resonant frequency area 301a or 301b and a second resonant frequency area 303a or 303b.
  • the vertical axis indicates a SlI value (dB)
  • the horizontal axis indicates frequency (MHz) .
  • the B graph (which is a case when the parasitic device switch is turned on) has smaller SIl value, compared to the A graph (which is a case when the parasitic device switch is turned off) .
  • the SIl value of the first resonant frequency area 301a is greater than the SIl value of the first resonant frequency area 301b.
  • the SIl value of the second resonant frequency area 303a is greater than the SIl value of the second resonant frequency area 303b. Therefore, when the parasitic device switch is turned on, impedance is matched well and the antenna radiation efficiency is high.
  • the frequency of the second resonant frequency area (between 303a and 303b) has a wide variance. Therefore, although it is possible to delicately control channel variance in the first resonant frequency area, it is impossible to delicately control channel variance in the second resonant frequency area.
  • the small antenna employing a parasitic device which is shown in Fig. 2, has a problem that it cannot delicately control transmitting/receiving signals in the second resonant frequency area, because the variance in the first resonant frequency area is minute whereas the variance in the second resonant frequency area is large according to on/off of the parasitic device switch.
  • it is required to develop a small multi-resonant antenna that can generate multiple resonant frequencies and delicately control frequency within a randomly selected resonant frequency in order to overcome the problems of the conventional small antenna employing a parasitic device.
  • An embodiment of the present invention which is devised to fulfill the above requirements, is directed to providing a small multi-resonant antenna that can widely vary resonant frequency and delicately control frequency within a randomly selected resonant frequency by using a parasitic device and multiple feeders.
  • an antenna element a plurality of feeders for supplying power to the antenna element; a parasitic device disposed in a dielectric region between a board where an antenna circuit is positioned and the antenna element; a feed switch for selectively connecting any one among the feeders to the antenna element to supply power to the antenna element; and a parasitic device switch for controlling the parasitic device.
  • the feeders are disposed in such a manner that a total length of the antenna element is different individually.
  • the present invention provides a small antenna with a parasitic device and multiple feeders inside.
  • the antenna can widely vary resonant frequency, can receive signals of broad band, that is, signals of multiple bands, and delicately control frequency within a randomly selected resonant frequency.
  • Fig. 1 shows T-DMB frequency bandwidth and channel bandwidth that are used currently.
  • Fig. 2 is a view showing a typical small antenna employing a parasitic device.
  • Fig. 3 is a graph showing an SIl parameter according to on/off of the parasitic device switch in the small antenna of Fig. 2.
  • Fig. 4 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with an embodiment of the present invention.
  • Fig. 5 is a graph showing an SIl parameter according to a feeder when the parasitic device switch 413 is turned on in the small antenna of Fig. 4.
  • Fig. 6 is a graph showing an SIl parameter according to a feeder when the parasitic device switch is turned off in the small antenna of Fig. 4.
  • Fig. 7 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with another embodiment of the present invention .
  • Fig. 4 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with an embodiment of the present invention.
  • the small antenna of the present embodiment includes a conductor 401, a first feeder 403, a second feeder 405, a radio frequency (RF) switch 407, a circuit output unit 409, a parasitic device 411, a parasitic device switch 413, and a PCB edge plane (not shown) .
  • the PCB edge plane includes a circuit generally realized in antennas (for example, a structure connected to an RF device, such as an amplifier, a mixer, and an analog-to-digital (AD) converter) and a ground line.
  • the conductor 401 is an antenna element, and it transmits or receives signals to or from the outside.
  • the first feeder 403 and the second feeder 405 connect the circuit output unit 409 to the conductor 401, and they are set up in such a manner that the total length (from a feed point to an end of the antenna) of the conductor 401 varies for each feeder.
  • the RF switch 407 selectively connects the circuit output unit 409 to any one between the first feeder 403 and the second feeder 405 based on a control signal transmitted from the PCB edge plane (not shown) .
  • the circuit output unit 409 is connected to one between the first feeder 403 and the second feeder 405, the total length (from a feed point to an end of the antenna) of the conductor 401 is changed, which leads to a change in the resonance length of the antenna.
  • Fig. 4 shows two feeders, which are the first feeder 403 and the second feeder 405, the number of feeders may be 3, 4, 5 or any arbitrary number according to an embodiment of the present invention. Also, the total number of the conductor 401 should be varied according to the selected number of feeders. This will be described in detail hereafter with reference to Fig. 8.
  • the circuit output unit 409 is a feed point. Power is supplied from the PCB edge plane (not shown) to the conductor 401 through the first or second feeders 403 or 405. To take an example, a varactor diode or a varying capacitance may be used as the parasitic device 411.
  • the parasitic device 411 is disposed inside a dielectric plate between the conductor 401 and the PCB edge plane (not shown) .
  • Fig. 4 shows one parasitic device 411, a plurality of parasitic devices may be set up according to an embodiment of the present invention, and the parasitic devices may be controlled using the parasitic device switch 413. This will be described in detail hereinafter with reference to Fig. 7.
  • the parasitic device switch 413 connects the parasitic device 411 to a ground plane included in the PCB edge plane (not shown) based on a control signal under the control of the PCB edge plane (not shown) . In short, it connects or disconnects the parasitic device 411 to or from the ground plane according to on/off of the parasitic device switch 413.
  • the gap between the conductor 401 and the PCB edge plane (not shown) becomes narrow and thus capacitance components increase, which leads to a decrease in the reactance value.
  • the gap between the conductor 401 and the PCB edge plane (not shown) becomes wide and thus capacitance components decrease, which leads to an increase in the reactance value .
  • the reactance value of the antenna varies according to on/off of the parasitic device switch 413 and this makes it possible to delicately control frequency.
  • the RF switch 407 or the parasitic device switch 413 is controlled based on resonant frequency information of an LC switch or local oscillation frequency information which is selected in an intermediate frequency (IF) converter and applied to a mixer. Also, the RF switch 407 or the parasitic device switch 413 may perform switching by feeding back a signal-to-noise ratio of RF signals or IF signals until the signal-to-noise ratio becomes the maximum.
  • IF intermediate frequency
  • the circuit output unit 409 is connected to one feeder and disconnected from all the other feeders in the small antenna of the present invention.
  • Fig. 5 is a graph showing an SIl parameter according to a feeder when the parasitic device switch 413 is turned on in the small antenna of Fig. 4.
  • C graph shows a first resonant frequency area 501c and a second resonant frequency area 503c when the parasitic device switch is turned on and the circuit output unit 409 is connected to the first feeder 403.
  • D graph shows a first resonant frequency area 501d and a second resonant frequency area 503d when the parasitic device switch is turned on and the circuit output unit 409 is connected to the second feeder 405.
  • the vertical axis indicates an SIl value (dB) and the horizontal axis indicates frequency (MHz) .
  • the variance gap between the first resonant frequency areas 501c and 501d of the C and D graphs is small and the variance gap between the second resonant frequency areas 503c and 503d of the C and D graphs is small. Also, the SIl value of the first resonant frequency areas 501c and 501d of the C and D graphs is much smaller than -1OdB.
  • the variance gap of resonant frequency is so small that frequency can be delicately controlled. Furthermore, since the SIl values for the first resonant frequency 501c and 501d are small, impedance is matched well to thereby minimize reflection loss caused by impedance mismatch and increase the antenna efficiency.
  • Fig. 6 is a graph showing an SIl parameter according to a feeder when the parasitic device switch is turned off in the small antenna of Fig. 4.
  • E graph shows a first resonant frequency area 601e and a second resonant frequency area 603e when the parasitic device switch is turned on and the circuit output unit 409 is connected to the first feeder 403.
  • F graph shows a first resonant frequency area 601f and a second resonant frequency area 603f when the parasitic device switch is turned off and the circuit output unit 409 is connected to the second feeder 405.
  • the vertical axis indicates an SIl value (dB) and the horizontal axis indicates frequency (MHz) .
  • the variance gap between the first resonant frequency areas 601e and 60If of the E and F graphs is small and the variance gap between the second resonant frequency areas 603e and 603f of the E and F graphs is small.
  • the SIl value of the second resonant frequency areas 603e and 603f of the E and F graphs is much smaller than -1OdB.
  • the variance gap of resonant frequency is so small that frequency can be delicately controlled.
  • the SIl values for the second resonant frequency 603e and 603f are small, impedance is matched well to thereby minimize reflection loss caused by impedance mismatch and increase the antenna efficiency.
  • a variance gap between the first resonant frequencies 501c and 601e and a variance gap between the second resonant frequencies 503c and 603e are about 10 to 20 MHz, which is much wider than the channel variance gap shown in Fig. 1.
  • a variance gap between the first resonant frequencies 501d and 601f and a variance gap between the second resonant frequencies 503d and 603f are very wide.
  • the capacitance value of the parasitic device varies according to on/off of the parasitic device switch and the reactance of the antenna is changed. This widely varies the resonant frequency.
  • the small antenna of the present invention can effectively use the first resonant frequency and the second resonant frequency according to on/off of the parasitic device switch. Also, it can receive signals of T-DMB (ranging from 174MHz to 216 MHz) and DVB-H (ranging from 400MHz to 600 MHz) by reducing the length of the antenna by half to thereby extend the used frequency twice as wide.
  • T-DMB ranging from 174MHz to 216 MHz
  • DVB-H ranging from 400MHz to 600 MHz
  • the small antenna of the present invention can widely vary the resonant frequency by using a parasitic device and it can also delicately control the resonant frequency by varying the total length of the antenna with multiple feeders.
  • Fig. 7 illustrates a small antenna using a parasitic device and multiple feeders in accordance with another embodiment of the present invention.
  • the antenna of the present embodiment includes a third feeder 701 and a second parasitic device 703 in addition to the structure of the small antenna shown in Fig. 4.
  • the small antenna of the present embodiment includes multiple feeders and multiple parasitic devices.
  • the parasitic device 411 will be referred to as a first parasitic device 411 to be distinguished from the second parasitic device 703.
  • the RF switch 407 selectively connects the circuit output unit 409 to any one among the first feeder 403, the second feeder 405, and the third feeder 701, and the parasitic device switch 413 controls the first parasitic device 411 and the second parasitic device 903. Since different resonant frequencies are selected according to the total length of the antenna which is variable, three resonant frequencies having delicate differences between them are generated according to the variance of the total length caused by the three feeders .
  • the parasitic device switch 413 can selectively connect one of the first parasitic device 411 and the second parasitic device 703 to the ground plane and, at the same time, connect both the first parasitic device 411 and the second parasitic device 703 to the ground plane.
  • the parasitic device is connected to the ground plane selectively or simultaneously so as to selectively transmit/receive signals corresponding to the first resonant frequency 501c, 501d, 601e or 60If or signals corresponding to the second resonant frequency 503c, 503d, 603e or 603f, and to maintain impedance matched.
  • the small antenna employing a parasitic device and multiple feeder which is suggested in the present invention and described with reference to Figs. 4 to 7, can be applied to an inverted F antenna such as a Planar Inverted-F Antenna (PIFA), a meander-type antenna, a helical antenna, a spring-type loop antenna and so forth. Also, it can be applied to small antennas with less than 1/4 wavelength, such as a Spiral Top Loaded Monopole Antenna (STLA) , a capacitor-plate antenna, a multielement top-loaded monopole antenna and the like.
  • PIFA Planar Inverted-F Antenna
  • STLA Spiral Top Loaded Monopole Antenna
  • STLA Spiral Top Loaded Monopole Antenna
  • capacitor-plate antenna a capacitor-plate antenna
  • multielement top-loaded monopole antenna and the like.
  • the method of the present invention can be realized as a program and stored in a computer-readable recording medium such as CD-ROM, RAM, ROM, floppy disks, hard disks, magneto-optical disks and the like. Since this process can be easily implemented by those of ordinary skill in the art to which the present pertains, detailed description will not be provided herein.
  • the present invention provides a small antenna that can widely vary resonant frequency and delicately control frequency within a randomly selected resonant frequency.

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

Abstract

Provided is a small multi-resonant antenna, which includes an antenna element; a plurality of feeders for supplying power to the antenna element; a parasitic device disposed in a dielectric region between a board where an antenna circuit is positioned and the antenna element; a feed switch for selectively connecting any one among the feeders to the antenna element to supply power to the antenna element; and a parasitic device switch for controlling the parasitic device. Herein the feeders are disposed in such a manner that a total length of the antenna element is different individually. The present invention provides an antenna that can widely vary resonant frequency and delicately control frequency within a randomly selected resonant frequency, and a manufacturing method thereof.

Description

DESCRIPTION
MULTI RESONANT ANTENNA
TECHNICAL FIELD The present invention relates to a small multi- resonant antenna; and, more particularly, to a small multi-resonant antenna having a wideband characteristic and capable of widely varying resonant frequencies and delicately adjusting frequency within a randomly selected resonant frequency.
This work was supported by IT R&D program of MIC/IITA. ["Development of Antenna Measurement System Technology. "]
BACKGROUND ART
In general, antennas have narrowband characteristics and when they are miniaturized, their antenna radiation patterns have omni-directional characteristics and their antenna gains decrease. Also, input resistance of an antenna becomes very small and reactance becomes very high. Thus, the bandwidth of the antenna becomes narrow.
Following Digital Television (DTV) services, audio, video and broadcasting services using ultrahigh frequency (UHF) bands such as Terrestrial Digital Multimedia Broadcasting (T-DMB) , Digital Video Broadcasting-Handheld (DVB-H), Satellite Digital Multimedia Broadcasting (S- DMB) , and Digital Audio Broadcasting (DAB) have been launched recently. The frequency bands used in the services belong to low frequency bands, whose wavelength is longer than the length of a mobile phone. A conventional 1/4 wavelength monopole antenna (for example, the wavelength of T-DMB is about 40cm) is longer than a mobile phone. Thus, it is inconvenient to use the antenna and the antenna can be hardly embedded inside a mobile phone.
In an effort to resolve the problems, researchers are accelerating development of small antennas.
Since small antennas occupy physically small space, the bandwidth of small antennas is limited so as to maintain excellent antenna efficiency. Herein, antenna efficiency is a ratio between power radiated from an antenna and power supplied to the antenna.
The audio, video and broadcasting services have a problem that radio frequency (RF) signals have too wide frequency band to be covered with one small antenna. In other words, since small antennas have limited maximal bandwidth, a single small antenna cannot afford receiving RF signals of entire bandwidths. For example, the maximal bandwidth that a 1/25 wavelength small antenna can acquire while maintaining fine antenna efficiency lies within about 3% around center frequency. On the other hand, the bandwidth of T- DMB (which ranges from 174MHz to 216MHz) occupies about 22% around the center frequency. Therefore, one antenna cannot accommodate the frequency bandwidth.
In addition to T-DMB, DVB-H, S-DMB, and DAB, recent mobile phones provide diverse wireless communication services such as Code Division Multiple Access (CDMA) , Global System for Mobile Telecommunication (GSM), Personal Communication Services (PCS), voice communication, an active/passive Radio Frequency Identification (RFID) reader function, a reception function of an FM radio broadcasting service, Bluetooth service and so forth. To support such technologies, an antenna capable of transmitting/receiving signals in multiple bands is required.
Fig. 1 shows T-DMB frequency bandwidth and channel bandwidth that are used currently. Referring to Fig. 1, the T-DMB frequency bandwidth includes a plurality of channel bandwidths . Although the T-DMB frequency bandwidth is 42 MHz, one channel bandwidth is very narrow, i.e., 1.536MHz. When one channel is received, the channel bandwidth of another channel is not used. Therefore, it is possible for one small antenna to receive signals of wideband by switching channels .
In other words, it is possible for one small antenna to receive signals of multiple channels by independently generating multiple resonant frequencies. This makes it possible for a single small antenna to receive signals of wideband. If any, the bandwidth of the small antenna should be wider than the channel bandwidth shown in Fig. 1. According to a prior art, the resonant frequency of an antenna is controlled by installing a parasitic device or an RF module and varying inductance or capacitance to make a reactance value of the antenna to be 0. Fig. 2 is a view showing a typical small antenna employing a parasitic device.
Referring to Fig. 2, the small antenna employing a parasitic device controls resonant frequency by using a varactor diode and varying capacitance to change inductance or capacitance.
The small antenna employing a parasitic device includes a conductor 201, a circuit output unit 203, a parasitic device 205, a parasitic device switch 207, and a Printed Circuit Board (PCB) edge plane (not shown) . Herein, the PCB edge plane (not shown) includes a circuit generally realized in antennas and a ground line.
The conductor 201 is an antenna element. It transmits or receives signals to or from the outside.
The circuit output unit 203 supplies power from the PCB edge plane (not shown) to the conductor 201. As for the parasitic device 205, a varactor diode or a varying capacitance may be used.
The parasitic device switch 207 connects the parasitic device 205 to a ground plane included in the PCB edge plane (not shown) based on a control signal under the control of the PCB edge plane (not shown) . In other words, the parasitic device 205 is connected to or disconnected from the antenna circuit upon on/off of the parasitic device switch 207. The varactor diode or the varying capacitance sensitively reacts with a surrounding environment (such as static electricity caused by hand or hair), and devices such as varactor diodes which require bias voltage supplied regularly for each product can hardly maintain a predetermined capacitance value. Therefore, it is hard to generate resonant frequency of a predetermined level. Also, when the parasitic device is connected to or disconnected from the ground plane, the reactance value varies so much that the resonant frequencies cannot be delicately adjusted to include all channels for T-DMB, S-DMB, DVB-H and D-TV. Furthermore, since the reactance value of the parasitic device is synthetically determined based on the aperture, shape and position of the parasitic device, capacitance, and inductance, it is difficult to predict the variance of the resonant frequency.
Fig. 3 is a graph showing an SIl parameter according to on/off of the parasitic device switch in the small antenna of Fig. 2. The antenna is a disconnected line. The ends of the antenna resonate in predetermined frequency. Thus, signals are not totally reflected and they are delivered to the outside as a specific electromagnetic energy. In short, an antenna is basically a one-port device whose input port is one. Thus, the antenna has only an SlI value which signifies an input reflection coefficient, and the antenna has the minimal SlI value (dB) in operation frequency. In the frequency where the SlI value is the minimum, signal power inputted to the antenna is radiated maximally. In other words, impedance is best matched at a point where the SIl value is the minimum.
Therefore, the smaller the SIl value is, the higher the radiation efficiency of the antenna grows high. Also, the smaller the quality factor of the SIl value is, the wider the frequency bandwidth used in the antenna becomes .
As shown in Fig. 3, A graph shows a case when the parasitic device switch is turned off, and B graph shows a case when the parasitic device switch is turned on. Both A and B graphs include a first resonant frequency area 301a or 301b and a second resonant frequency area 303a or 303b. Herein, the vertical axis indicates a SlI value (dB) , whereas the horizontal axis indicates frequency (MHz) .
In the first and second resonant frequency areas, the B graph (which is a case when the parasitic device switch is turned on) has smaller SIl value, compared to the A graph (which is a case when the parasitic device switch is turned off) . In short, the SIl value of the first resonant frequency area 301a is greater than the SIl value of the first resonant frequency area 301b. Also, the SIl value of the second resonant frequency area 303a is greater than the SIl value of the second resonant frequency area 303b. Therefore, when the parasitic device switch is turned on, impedance is matched well and the antenna radiation efficiency is high.
Although there is a minute difference in the first resonant frequency areas 301a and 301b according to whether the parasitic device switch is turned on or off, the frequency of the second resonant frequency area (between 303a and 303b) has a wide variance. Therefore, although it is possible to delicately control channel variance in the first resonant frequency area, it is impossible to delicately control channel variance in the second resonant frequency area.
To sum up, the small antenna employing a parasitic device, which is shown in Fig. 2, has a problem that it cannot delicately control transmitting/receiving signals in the second resonant frequency area, because the variance in the first resonant frequency area is minute whereas the variance in the second resonant frequency area is large according to on/off of the parasitic device switch. As described above, it is required to develop a small multi-resonant antenna that can generate multiple resonant frequencies and delicately control frequency within a randomly selected resonant frequency in order to overcome the problems of the conventional small antenna employing a parasitic device.
DISCLOSURE TECHNICAL PROBLEM
An embodiment of the present invention, which is devised to fulfill the above requirements, is directed to providing a small multi-resonant antenna that can widely vary resonant frequency and delicately control frequency within a randomly selected resonant frequency by using a parasitic device and multiple feeders.
TECHNICAL SOLUTION
In accordance with an aspect of the present invention, there is provided an antenna element; a plurality of feeders for supplying power to the antenna element; a parasitic device disposed in a dielectric region between a board where an antenna circuit is positioned and the antenna element; a feed switch for selectively connecting any one among the feeders to the antenna element to supply power to the antenna element; and a parasitic device switch for controlling the parasitic device. Herein the feeders are disposed in such a manner that a total length of the antenna element is different individually.
ADVANTAGEOUS EFFECTS
The present invention provides a small antenna with a parasitic device and multiple feeders inside. The antenna can widely vary resonant frequency, can receive signals of broad band, that is, signals of multiple bands, and delicately control frequency within a randomly selected resonant frequency.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 shows T-DMB frequency bandwidth and channel bandwidth that are used currently.
Fig. 2 is a view showing a typical small antenna employing a parasitic device.
Fig. 3 is a graph showing an SIl parameter according to on/off of the parasitic device switch in the small antenna of Fig. 2.
Fig. 4 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with an embodiment of the present invention.
Fig. 5 is a graph showing an SIl parameter according to a feeder when the parasitic device switch 413 is turned on in the small antenna of Fig. 4.
Fig. 6 is a graph showing an SIl parameter according to a feeder when the parasitic device switch is turned off in the small antenna of Fig. 4. Fig. 7 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with another embodiment of the present invention .
BEST MODE FOR THE INVENTION
The advantages, features and aspects of the invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, which is set forth hereinafter. Fig. 4 is a view illustrating a small antenna using a parasitic device and multiple feeders in accordance with an embodiment of the present invention.
Referring to Fig. 4, the small antenna of the present embodiment includes a conductor 401, a first feeder 403, a second feeder 405, a radio frequency (RF) switch 407, a circuit output unit 409, a parasitic device 411, a parasitic device switch 413, and a PCB edge plane (not shown) . The PCB edge plane (not shown) includes a circuit generally realized in antennas (for example, a structure connected to an RF device, such as an amplifier, a mixer, and an analog-to-digital (AD) converter) and a ground line.
The conductor 401 is an antenna element, and it transmits or receives signals to or from the outside. The first feeder 403 and the second feeder 405 connect the circuit output unit 409 to the conductor 401, and they are set up in such a manner that the total length (from a feed point to an end of the antenna) of the conductor 401 varies for each feeder. The RF switch 407 selectively connects the circuit output unit 409 to any one between the first feeder 403 and the second feeder 405 based on a control signal transmitted from the PCB edge plane (not shown) . As the circuit output unit 409 is connected to one between the first feeder 403 and the second feeder 405, the total length (from a feed point to an end of the antenna) of the conductor 401 is changed, which leads to a change in the resonance length of the antenna.
Although Fig. 4 shows two feeders, which are the first feeder 403 and the second feeder 405, the number of feeders may be 3, 4, 5 or any arbitrary number according to an embodiment of the present invention. Also, the total number of the conductor 401 should be varied according to the selected number of feeders. This will be described in detail hereafter with reference to Fig. 8. The circuit output unit 409 is a feed point. Power is supplied from the PCB edge plane (not shown) to the conductor 401 through the first or second feeders 403 or 405. To take an example, a varactor diode or a varying capacitance may be used as the parasitic device 411. Also, the parasitic device 411 is disposed inside a dielectric plate between the conductor 401 and the PCB edge plane (not shown) . Although Fig. 4 shows one parasitic device 411, a plurality of parasitic devices may be set up according to an embodiment of the present invention, and the parasitic devices may be controlled using the parasitic device switch 413. This will be described in detail hereinafter with reference to Fig. 7.
The parasitic device switch 413 connects the parasitic device 411 to a ground plane included in the PCB edge plane (not shown) based on a control signal under the control of the PCB edge plane (not shown) . In short, it connects or disconnects the parasitic device 411 to or from the ground plane according to on/off of the parasitic device switch 413.
Herein, when the parasitic device switch 413 is turned on, the gap between the conductor 401 and the PCB edge plane (not shown) becomes narrow and thus capacitance components increase, which leads to a decrease in the reactance value. Reversely, when the parasitic device switch 413 is turned off, the gap between the conductor 401 and the PCB edge plane (not shown) becomes wide and thus capacitance components decrease, which leads to an increase in the reactance value .
In short, the reactance value of the antenna varies according to on/off of the parasitic device switch 413 and this makes it possible to delicately control frequency.
The RF switch 407 or the parasitic device switch 413 is controlled based on resonant frequency information of an LC switch or local oscillation frequency information which is selected in an intermediate frequency (IF) converter and applied to a mixer. Also, the RF switch 407 or the parasitic device switch 413 may perform switching by feeding back a signal-to-noise ratio of RF signals or IF signals until the signal-to-noise ratio becomes the maximum.
When the RF switch 407 is simultaneously connected to a plurality of feeders, it can be regarded as one antenna. Therefore, it has a limited bandwidth according to the maximal bandwidth of a small antenna. Therefore, the circuit output unit 409 is connected to one feeder and disconnected from all the other feeders in the small antenna of the present invention.
Fig. 5 is a graph showing an SIl parameter according to a feeder when the parasitic device switch 413 is turned on in the small antenna of Fig. 4.
Referring to Fig. 5, C graph shows a first resonant frequency area 501c and a second resonant frequency area 503c when the parasitic device switch is turned on and the circuit output unit 409 is connected to the first feeder 403. D graph shows a first resonant frequency area 501d and a second resonant frequency area 503d when the parasitic device switch is turned on and the circuit output unit 409 is connected to the second feeder 405. Herein, the vertical axis indicates an SIl value (dB) and the horizontal axis indicates frequency (MHz) .
When the parasitic device switch is turned on, the variance gap between the first resonant frequency areas 501c and 501d of the C and D graphs is small and the variance gap between the second resonant frequency areas 503c and 503d of the C and D graphs is small. Also, the SIl value of the first resonant frequency areas 501c and 501d of the C and D graphs is much smaller than -1OdB.
In short, when the parasitic device switch is turned on and the first feeder 403 or the second feeder 405 is in connection in the small antenna of Fig. 4, the variance gap of resonant frequency is so small that frequency can be delicately controlled. Furthermore, since the SIl values for the first resonant frequency 501c and 501d are small, impedance is matched well to thereby minimize reflection loss caused by impedance mismatch and increase the antenna efficiency.
Therefore, when the parasitic device switch is turned on, frequency can be delicately controlled for signals of the first resonant frequency and the antenna efficiency is high.
Fig. 6 is a graph showing an SIl parameter according to a feeder when the parasitic device switch is turned off in the small antenna of Fig. 4. Referring to Fig. 6, E graph shows a first resonant frequency area 601e and a second resonant frequency area 603e when the parasitic device switch is turned on and the circuit output unit 409 is connected to the first feeder 403. F graph shows a first resonant frequency area 601f and a second resonant frequency area 603f when the parasitic device switch is turned off and the circuit output unit 409 is connected to the second feeder 405. Herein, the vertical axis indicates an SIl value (dB) and the horizontal axis indicates frequency (MHz) .
When the parasitic device switch is turned off, the variance gap between the first resonant frequency areas 601e and 60If of the E and F graphs is small and the variance gap between the second resonant frequency areas 603e and 603f of the E and F graphs is small. Also, the SIl value of the second resonant frequency areas 603e and 603f of the E and F graphs is much smaller than -1OdB. In short, when the parasitic device switch is turned off and the first feeder 403 or the second feeder 405 is in connection in the small antenna of Fig. 4, the variance gap of resonant frequency is so small that frequency can be delicately controlled. Furthermore, since the SIl values for the second resonant frequency 603e and 603f are small, impedance is matched well to thereby minimize reflection loss caused by impedance mismatch and increase the antenna efficiency.
Therefore, when the parasitic device switch is turned off, frequency can be delicately controlled for signals of the second resonant frequency and the antenna efficiency is high.
To have a look at the variance according to on/off of the parasitic device switch with reference to Figs. 5 and 6 when the first feeder 403 is in connection, a variance gap between the first resonant frequencies 501c and 601e and a variance gap between the second resonant frequencies 503c and 603e are about 10 to 20 MHz, which is much wider than the channel variance gap shown in Fig. 1. Also, when the second feeder 405 is in connection, a variance gap between the first resonant frequencies 501d and 601f and a variance gap between the second resonant frequencies 503d and 603f are very wide.
To sum up, the capacitance value of the parasitic device varies according to on/off of the parasitic device switch and the reactance of the antenna is changed. This widely varies the resonant frequency.
Therefore, it is possible to widely vary frequency by using a parasitic device, and to delicately vary channels within the widely varied resonant frequency by using multiple feeders. In short, it is possible to change the channel both delicately and widely, and to change frequency band for another service by selecting a corresponding parasitic device.
As shown in Figs. 5 and 6, the small antenna of the present invention can effectively use the first resonant frequency and the second resonant frequency according to on/off of the parasitic device switch. Also, it can receive signals of T-DMB (ranging from 174MHz to 216 MHz) and DVB-H (ranging from 400MHz to 600 MHz) by reducing the length of the antenna by half to thereby extend the used frequency twice as wide.
Referring to Figs. 4 to 6, the small antenna of the present invention can widely vary the resonant frequency by using a parasitic device and it can also delicately control the resonant frequency by varying the total length of the antenna with multiple feeders.
Fig. 7 illustrates a small antenna using a parasitic device and multiple feeders in accordance with another embodiment of the present invention. The antenna of the present embodiment includes a third feeder 701 and a second parasitic device 703 in addition to the structure of the small antenna shown in Fig. 4.
Referring to Fig. 7, the small antenna of the present embodiment includes multiple feeders and multiple parasitic devices. Herein, the parasitic device 411 will be referred to as a first parasitic device 411 to be distinguished from the second parasitic device 703.
The RF switch 407 selectively connects the circuit output unit 409 to any one among the first feeder 403, the second feeder 405, and the third feeder 701, and the parasitic device switch 413 controls the first parasitic device 411 and the second parasitic device 903. Since different resonant frequencies are selected according to the total length of the antenna which is variable, three resonant frequencies having delicate differences between them are generated according to the variance of the total length caused by the three feeders .
Differently from the RF switch 407 capable of connecting only one feeder, the parasitic device switch 413 can selectively connect one of the first parasitic device 411 and the second parasitic device 703 to the ground plane and, at the same time, connect both the first parasitic device 411 and the second parasitic device 703 to the ground plane. The parasitic device is connected to the ground plane selectively or simultaneously so as to selectively transmit/receive signals corresponding to the first resonant frequency 501c, 501d, 601e or 60If or signals corresponding to the second resonant frequency 503c, 503d, 603e or 603f, and to maintain impedance matched. The small antenna employing a parasitic device and multiple feeder, which is suggested in the present invention and described with reference to Figs. 4 to 7, can be applied to an inverted F antenna such as a Planar Inverted-F Antenna (PIFA), a meander-type antenna, a helical antenna, a spring-type loop antenna and so forth. Also, it can be applied to small antennas with less than 1/4 wavelength, such as a Spiral Top Loaded Monopole Antenna (STLA) , a capacitor-plate antenna, a multielement top-loaded monopole antenna and the like. The method of the present invention can be realized as a program and stored in a computer-readable recording medium such as CD-ROM, RAM, ROM, floppy disks, hard disks, magneto-optical disks and the like. Since this process can be easily implemented by those of ordinary skill in the art to which the present pertains, detailed description will not be provided herein.
While the present invention has been described with respect to certain preferred embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined in the following claims.
Industrial Applicability
The present invention provides a small antenna that can widely vary resonant frequency and delicately control frequency within a randomly selected resonant frequency.

Claims

WHAT IS CLAIMED IS
1. An antenna, comprising: an antenna element; a plurality of feeders for supplying power to the antenna element; a parasitic device disposed in a dielectric region between a board where an antenna circuit is positioned and the antenna element; a feed switch for selectively connecting any one among the feeders to the antenna element to supply power to the antenna element; and a parasitic device switch for controlling the parasitic device, wherein the feeders are disposed in such a manner that a total length of the antenna element is different for each feeder.
2. The antenna of claim 1, wherein the number of the parasitic device is plural.
3. The antenna of claim 2, wherein the parasitic device switch controls at least any one of the parasitic devices to be turned on/off.
4. The antenna of claim 1, wherein the parasitic device is a varactor diode.
5. The antenna of claim 1, wherein the parasitic device is a varying capacitance.
6. The antenna of claim 1, wherein a reactance component of the antenna varies according to operation of the parasitic device switch.
7. The antenna of claim 6, wherein a capacitance value of the parasitic device varies according to operation of the parasitic device switch.
8. The antenna of claim 1, whose maximal radius is less than 1/4 wavelength.
9. The antenna of claim 1, wherein the antenna element is a Planar Inverted-F Antenna (PIFA) .
10. The antenna of claim 1, wherein the antenna element is a meander-type antenna.
11. The antenna of claim 1, wherein the antenna element is a helical antenna.
12. The antenna of claim 1, wherein the antenna element is a spring-type loop antenna.
13. The antenna of claim 1, wherein the antenna element is a Spiral Top Loaded Monopole Antenna (STLA) .
14. The antenna of claim 1, wherein the antenna element is a capacitor-plate antenna.
15. The antenna of claim 1, wherein the antenna element is a multi-element top-loaded monopole antenna.
16. The antenna of claim 1, wherein the antenna element is an inverted F antenna.
EP07833611A 2006-10-26 2007-10-26 MULTI-RESONANT ANTENNA Ceased EP2087551A4 (en)

Applications Claiming Priority (3)

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KR20060104642 2006-10-26
KR1020070107738A KR100989064B1 (en) 2006-10-26 2007-10-25 Multiple resonant antenna
PCT/KR2007/005302 WO2008051044A1 (en) 2006-10-26 2007-10-26 Multi resonant antenna

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Families Citing this family (151)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101393829B1 (en) 2012-10-04 2014-05-12 엘지이노텍 주식회사 Communication terminal, antenna apparatus thereof, and driving method thereof
US9113347B2 (en) 2012-12-05 2015-08-18 At&T Intellectual Property I, Lp Backhaul link for distributed antenna system
US10009065B2 (en) 2012-12-05 2018-06-26 At&T Intellectual Property I, L.P. Backhaul link for distributed antenna system
KR101470130B1 (en) * 2013-03-13 2014-12-05 엘지이노텍 주식회사 Antenna apparatus and feeding structure thereof
KR101449260B1 (en) * 2013-03-28 2014-10-10 엘지이노텍 주식회사 Antenna apparatus and feeding structure thereof
US9525524B2 (en) 2013-05-31 2016-12-20 At&T Intellectual Property I, L.P. Remote distributed antenna system
US9999038B2 (en) 2013-05-31 2018-06-12 At&T Intellectual Property I, L.P. Remote distributed antenna system
TW201503488A (en) * 2013-07-02 2015-01-16 Ming-Hao Yeh Active antenna system with multiple feed ports and associated control met hod
US8897697B1 (en) 2013-11-06 2014-11-25 At&T Intellectual Property I, Lp Millimeter-wave surface-wave communications
US9692101B2 (en) 2014-08-26 2017-06-27 At&T Intellectual Property I, L.P. Guided wave couplers for coupling electromagnetic waves between a waveguide surface and a surface of a wire
US9768833B2 (en) 2014-09-15 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for sensing a condition in a transmission medium of electromagnetic waves
US10063280B2 (en) 2014-09-17 2018-08-28 At&T Intellectual Property I, L.P. Monitoring and mitigating conditions in a communication network
US9615269B2 (en) 2014-10-02 2017-04-04 At&T Intellectual Property I, L.P. Method and apparatus that provides fault tolerance in a communication network
US9685992B2 (en) 2014-10-03 2017-06-20 At&T Intellectual Property I, L.P. Circuit panel network and methods thereof
US9503189B2 (en) 2014-10-10 2016-11-22 At&T Intellectual Property I, L.P. Method and apparatus for arranging communication sessions in a communication system
US9973299B2 (en) 2014-10-14 2018-05-15 At&T Intellectual Property I, L.P. Method and apparatus for adjusting a mode of communication in a communication network
US9762289B2 (en) 2014-10-14 2017-09-12 At&T Intellectual Property I, L.P. Method and apparatus for transmitting or receiving signals in a transportation system
US9769020B2 (en) 2014-10-21 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for responding to events affecting communications in a communication network
US9577306B2 (en) 2014-10-21 2017-02-21 At&T Intellectual Property I, L.P. Guided-wave transmission device and methods for use therewith
US9653770B2 (en) 2014-10-21 2017-05-16 At&T Intellectual Property I, L.P. Guided wave coupler, coupling module and methods for use therewith
US9520945B2 (en) 2014-10-21 2016-12-13 At&T Intellectual Property I, L.P. Apparatus for providing communication services and methods thereof
US9627768B2 (en) 2014-10-21 2017-04-18 At&T Intellectual Property I, L.P. Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith
US9312919B1 (en) 2014-10-21 2016-04-12 At&T Intellectual Property I, Lp Transmission device with impairment compensation and methods for use therewith
US9780834B2 (en) 2014-10-21 2017-10-03 At&T Intellectual Property I, L.P. Method and apparatus for transmitting electromagnetic waves
US10569028B2 (en) 2014-11-05 2020-02-25 Insuline Medical Ltd. Drug tracking device
US10340573B2 (en) 2016-10-26 2019-07-02 At&T Intellectual Property I, L.P. Launcher with cylindrical coupling device and methods for use therewith
US9461706B1 (en) 2015-07-31 2016-10-04 At&T Intellectual Property I, Lp Method and apparatus for exchanging communication signals
US10243784B2 (en) 2014-11-20 2019-03-26 At&T Intellectual Property I, L.P. System for generating topology information and methods thereof
US9800327B2 (en) 2014-11-20 2017-10-24 At&T Intellectual Property I, L.P. Apparatus for controlling operations of a communication device and methods thereof
US9544006B2 (en) 2014-11-20 2017-01-10 At&T Intellectual Property I, L.P. Transmission device with mode division multiplexing and methods for use therewith
US9954287B2 (en) 2014-11-20 2018-04-24 At&T Intellectual Property I, L.P. Apparatus for converting wireless signals and electromagnetic waves and methods thereof
US9997819B2 (en) 2015-06-09 2018-06-12 At&T Intellectual Property I, L.P. Transmission medium and method for facilitating propagation of electromagnetic waves via a core
US10009067B2 (en) 2014-12-04 2018-06-26 At&T Intellectual Property I, L.P. Method and apparatus for configuring a communication interface
US9742462B2 (en) 2014-12-04 2017-08-22 At&T Intellectual Property I, L.P. Transmission medium and communication interfaces and methods for use therewith
US10144036B2 (en) 2015-01-30 2018-12-04 At&T Intellectual Property I, L.P. Method and apparatus for mitigating interference affecting a propagation of electromagnetic waves guided by a transmission medium
US9876570B2 (en) 2015-02-20 2018-01-23 At&T Intellectual Property I, Lp Guided-wave transmission device with non-fundamental mode propagation and methods for use therewith
US9749013B2 (en) 2015-03-17 2017-08-29 At&T Intellectual Property I, L.P. Method and apparatus for reducing attenuation of electromagnetic waves guided by a transmission medium
US9705561B2 (en) 2015-04-24 2017-07-11 At&T Intellectual Property I, L.P. Directional coupling device and methods for use therewith
US10224981B2 (en) 2015-04-24 2019-03-05 At&T Intellectual Property I, Lp Passive electrical coupling device and methods for use therewith
US9948354B2 (en) 2015-04-28 2018-04-17 At&T Intellectual Property I, L.P. Magnetic coupling device with reflective plate and methods for use therewith
US9793954B2 (en) 2015-04-28 2017-10-17 At&T Intellectual Property I, L.P. Magnetic coupling device and methods for use therewith
US9490869B1 (en) 2015-05-14 2016-11-08 At&T Intellectual Property I, L.P. Transmission medium having multiple cores and methods for use therewith
US9748626B2 (en) 2015-05-14 2017-08-29 At&T Intellectual Property I, L.P. Plurality of cables having different cross-sectional shapes which are bundled together to form a transmission medium
US9871282B2 (en) 2015-05-14 2018-01-16 At&T Intellectual Property I, L.P. At least one transmission medium having a dielectric surface that is covered at least in part by a second dielectric
US10650940B2 (en) 2015-05-15 2020-05-12 At&T Intellectual Property I, L.P. Transmission medium having a conductive material and methods for use therewith
US9917341B2 (en) 2015-05-27 2018-03-13 At&T Intellectual Property I, L.P. Apparatus and method for launching electromagnetic waves and for modifying radial dimensions of the propagating electromagnetic waves
US9912381B2 (en) 2015-06-03 2018-03-06 At&T Intellectual Property I, Lp Network termination and methods for use therewith
US9866309B2 (en) 2015-06-03 2018-01-09 At&T Intellectual Property I, Lp Host node device and methods for use therewith
US10103801B2 (en) 2015-06-03 2018-10-16 At&T Intellectual Property I, L.P. Host node device and methods for use therewith
US10812174B2 (en) 2015-06-03 2020-10-20 At&T Intellectual Property I, L.P. Client node device and methods for use therewith
US9913139B2 (en) 2015-06-09 2018-03-06 At&T Intellectual Property I, L.P. Signal fingerprinting for authentication of communicating devices
US10142086B2 (en) 2015-06-11 2018-11-27 At&T Intellectual Property I, L.P. Repeater and methods for use therewith
US9608692B2 (en) 2015-06-11 2017-03-28 At&T Intellectual Property I, L.P. Repeater and methods for use therewith
US9820146B2 (en) 2015-06-12 2017-11-14 At&T Intellectual Property I, L.P. Method and apparatus for authentication and identity management of communicating devices
US9667317B2 (en) 2015-06-15 2017-05-30 At&T Intellectual Property I, L.P. Method and apparatus for providing security using network traffic adjustments
US9509415B1 (en) 2015-06-25 2016-11-29 At&T Intellectual Property I, L.P. Methods and apparatus for inducing a fundamental wave mode on a transmission medium
US9640850B2 (en) 2015-06-25 2017-05-02 At&T Intellectual Property I, L.P. Methods and apparatus for inducing a non-fundamental wave mode on a transmission medium
US9865911B2 (en) 2015-06-25 2018-01-09 At&T Intellectual Property I, L.P. Waveguide system for slot radiating first electromagnetic waves that are combined into a non-fundamental wave mode second electromagnetic wave on a transmission medium
US9853342B2 (en) 2015-07-14 2017-12-26 At&T Intellectual Property I, L.P. Dielectric transmission medium connector and methods for use therewith
US10170840B2 (en) 2015-07-14 2019-01-01 At&T Intellectual Property I, L.P. Apparatus and methods for sending or receiving electromagnetic signals
US10044409B2 (en) 2015-07-14 2018-08-07 At&T Intellectual Property I, L.P. Transmission medium and methods for use therewith
US9882257B2 (en) 2015-07-14 2018-01-30 At&T Intellectual Property I, L.P. Method and apparatus for launching a wave mode that mitigates interference
US10033107B2 (en) 2015-07-14 2018-07-24 At&T Intellectual Property I, L.P. Method and apparatus for coupling an antenna to a device
US10033108B2 (en) 2015-07-14 2018-07-24 At&T Intellectual Property I, L.P. Apparatus and methods for generating an electromagnetic wave having a wave mode that mitigates interference
US10341142B2 (en) 2015-07-14 2019-07-02 At&T Intellectual Property I, L.P. Apparatus and methods for generating non-interfering electromagnetic waves on an uninsulated conductor
US9847566B2 (en) 2015-07-14 2017-12-19 At&T Intellectual Property I, L.P. Method and apparatus for adjusting a field of a signal to mitigate interference
US9628116B2 (en) 2015-07-14 2017-04-18 At&T Intellectual Property I, L.P. Apparatus and methods for transmitting wireless signals
US10148016B2 (en) 2015-07-14 2018-12-04 At&T Intellectual Property I, L.P. Apparatus and methods for communicating utilizing an antenna array
US10205655B2 (en) 2015-07-14 2019-02-12 At&T Intellectual Property I, L.P. Apparatus and methods for communicating utilizing an antenna array and multiple communication paths
US10320586B2 (en) 2015-07-14 2019-06-11 At&T Intellectual Property I, L.P. Apparatus and methods for generating non-interfering electromagnetic waves on an insulated transmission medium
US9722318B2 (en) 2015-07-14 2017-08-01 At&T Intellectual Property I, L.P. Method and apparatus for coupling an antenna to a device
US9608740B2 (en) 2015-07-15 2017-03-28 At&T Intellectual Property I, L.P. Method and apparatus for launching a wave mode that mitigates interference
US10090606B2 (en) 2015-07-15 2018-10-02 At&T Intellectual Property I, L.P. Antenna system with dielectric array and methods for use therewith
US9793951B2 (en) 2015-07-15 2017-10-17 At&T Intellectual Property I, L.P. Method and apparatus for launching a wave mode that mitigates interference
US9948333B2 (en) 2015-07-23 2018-04-17 At&T Intellectual Property I, L.P. Method and apparatus for wireless communications to mitigate interference
US9749053B2 (en) 2015-07-23 2017-08-29 At&T Intellectual Property I, L.P. Node device, repeater and methods for use therewith
US9871283B2 (en) 2015-07-23 2018-01-16 At&T Intellectual Property I, Lp Transmission medium having a dielectric core comprised of plural members connected by a ball and socket configuration
US9912027B2 (en) 2015-07-23 2018-03-06 At&T Intellectual Property I, L.P. Method and apparatus for exchanging communication signals
US9735833B2 (en) 2015-07-31 2017-08-15 At&T Intellectual Property I, L.P. Method and apparatus for communications management in a neighborhood network
US9967173B2 (en) 2015-07-31 2018-05-08 At&T Intellectual Property I, L.P. Method and apparatus for authentication and identity management of communicating devices
US9904535B2 (en) 2015-09-14 2018-02-27 At&T Intellectual Property I, L.P. Method and apparatus for distributing software
US10079661B2 (en) 2015-09-16 2018-09-18 At&T Intellectual Property I, L.P. Method and apparatus for use with a radio distributed antenna system having a clock reference
US10009063B2 (en) 2015-09-16 2018-06-26 At&T Intellectual Property I, L.P. Method and apparatus for use with a radio distributed antenna system having an out-of-band reference signal
US10136434B2 (en) 2015-09-16 2018-11-20 At&T Intellectual Property I, L.P. Method and apparatus for use with a radio distributed antenna system having an ultra-wideband control channel
US9769128B2 (en) 2015-09-28 2017-09-19 At&T Intellectual Property I, L.P. Method and apparatus for encryption of communications over a network
US9729197B2 (en) 2015-10-01 2017-08-08 At&T Intellectual Property I, L.P. Method and apparatus for communicating network management traffic over a network
US9876264B2 (en) 2015-10-02 2018-01-23 At&T Intellectual Property I, Lp Communication system, guided wave switch and methods for use therewith
US10665942B2 (en) 2015-10-16 2020-05-26 At&T Intellectual Property I, L.P. Method and apparatus for adjusting wireless communications
US10355367B2 (en) 2015-10-16 2019-07-16 At&T Intellectual Property I, L.P. Antenna structure for exchanging wireless signals
US9912419B1 (en) 2016-08-24 2018-03-06 At&T Intellectual Property I, L.P. Method and apparatus for managing a fault in a distributed antenna system
US9860075B1 (en) 2016-08-26 2018-01-02 At&T Intellectual Property I, L.P. Method and communication node for broadband distribution
US10291311B2 (en) 2016-09-09 2019-05-14 At&T Intellectual Property I, L.P. Method and apparatus for mitigating a fault in a distributed antenna system
US11032819B2 (en) 2016-09-15 2021-06-08 At&T Intellectual Property I, L.P. Method and apparatus for use with a radio distributed antenna system having a control channel reference signal
US10135147B2 (en) 2016-10-18 2018-11-20 At&T Intellectual Property I, L.P. Apparatus and methods for launching guided waves via an antenna
US10135146B2 (en) 2016-10-18 2018-11-20 At&T Intellectual Property I, L.P. Apparatus and methods for launching guided waves via circuits
US10340600B2 (en) 2016-10-18 2019-07-02 At&T Intellectual Property I, L.P. Apparatus and methods for launching guided waves via plural waveguide systems
US10374316B2 (en) 2016-10-21 2019-08-06 At&T Intellectual Property I, L.P. System and dielectric antenna with non-uniform dielectric
US9991580B2 (en) 2016-10-21 2018-06-05 At&T Intellectual Property I, L.P. Launcher and coupling system for guided wave mode cancellation
US10811767B2 (en) 2016-10-21 2020-10-20 At&T Intellectual Property I, L.P. System and dielectric antenna with convex dielectric radome
US10312567B2 (en) 2016-10-26 2019-06-04 At&T Intellectual Property I, L.P. Launcher with planar strip antenna and methods for use therewith
US10224634B2 (en) 2016-11-03 2019-03-05 At&T Intellectual Property I, L.P. Methods and apparatus for adjusting an operational characteristic of an antenna
US10291334B2 (en) 2016-11-03 2019-05-14 At&T Intellectual Property I, L.P. System for detecting a fault in a communication system
US10498044B2 (en) 2016-11-03 2019-12-03 At&T Intellectual Property I, L.P. Apparatus for configuring a surface of an antenna
US10225025B2 (en) 2016-11-03 2019-03-05 At&T Intellectual Property I, L.P. Method and apparatus for detecting a fault in a communication system
US10340601B2 (en) 2016-11-23 2019-07-02 At&T Intellectual Property I, L.P. Multi-antenna system and methods for use therewith
US10178445B2 (en) 2016-11-23 2019-01-08 At&T Intellectual Property I, L.P. Methods, devices, and systems for load balancing between a plurality of waveguides
US10090594B2 (en) 2016-11-23 2018-10-02 At&T Intellectual Property I, L.P. Antenna system having structural configurations for assembly
US10340603B2 (en) 2016-11-23 2019-07-02 At&T Intellectual Property I, L.P. Antenna system having shielded structural configurations for assembly
US10535928B2 (en) 2016-11-23 2020-01-14 At&T Intellectual Property I, L.P. Antenna system and methods for use therewith
US10361489B2 (en) 2016-12-01 2019-07-23 At&T Intellectual Property I, L.P. Dielectric dish antenna system and methods for use therewith
US10305190B2 (en) 2016-12-01 2019-05-28 At&T Intellectual Property I, L.P. Reflecting dielectric antenna system and methods for use therewith
US10326494B2 (en) 2016-12-06 2019-06-18 At&T Intellectual Property I, L.P. Apparatus for measurement de-embedding and methods for use therewith
US10637149B2 (en) 2016-12-06 2020-04-28 At&T Intellectual Property I, L.P. Injection molded dielectric antenna and methods for use therewith
US10382976B2 (en) 2016-12-06 2019-08-13 At&T Intellectual Property I, L.P. Method and apparatus for managing wireless communications based on communication paths and network device positions
US10819035B2 (en) 2016-12-06 2020-10-27 At&T Intellectual Property I, L.P. Launcher with helical antenna and methods for use therewith
US10439675B2 (en) 2016-12-06 2019-10-08 At&T Intellectual Property I, L.P. Method and apparatus for repeating guided wave communication signals
US10020844B2 (en) 2016-12-06 2018-07-10 T&T Intellectual Property I, L.P. Method and apparatus for broadcast communication via guided waves
US10135145B2 (en) 2016-12-06 2018-11-20 At&T Intellectual Property I, L.P. Apparatus and methods for generating an electromagnetic wave along a transmission medium
US9927517B1 (en) 2016-12-06 2018-03-27 At&T Intellectual Property I, L.P. Apparatus and methods for sensing rainfall
US10755542B2 (en) 2016-12-06 2020-08-25 At&T Intellectual Property I, L.P. Method and apparatus for surveillance via guided wave communication
US10694379B2 (en) 2016-12-06 2020-06-23 At&T Intellectual Property I, L.P. Waveguide system with device-based authentication and methods for use therewith
US10727599B2 (en) 2016-12-06 2020-07-28 At&T Intellectual Property I, L.P. Launcher with slot antenna and methods for use therewith
US10389029B2 (en) 2016-12-07 2019-08-20 At&T Intellectual Property I, L.P. Multi-feed dielectric antenna system with core selection and methods for use therewith
US10446936B2 (en) 2016-12-07 2019-10-15 At&T Intellectual Property I, L.P. Multi-feed dielectric antenna system and methods for use therewith
US10168695B2 (en) 2016-12-07 2019-01-01 At&T Intellectual Property I, L.P. Method and apparatus for controlling an unmanned aircraft
US10359749B2 (en) 2016-12-07 2019-07-23 At&T Intellectual Property I, L.P. Method and apparatus for utilities management via guided wave communication
US10139820B2 (en) 2016-12-07 2018-11-27 At&T Intellectual Property I, L.P. Method and apparatus for deploying equipment of a communication system
US9893795B1 (en) 2016-12-07 2018-02-13 At&T Intellectual Property I, Lp Method and repeater for broadband distribution
US10027397B2 (en) 2016-12-07 2018-07-17 At&T Intellectual Property I, L.P. Distributed antenna system and methods for use therewith
US10243270B2 (en) 2016-12-07 2019-03-26 At&T Intellectual Property I, L.P. Beam adaptive multi-feed dielectric antenna system and methods for use therewith
US10547348B2 (en) 2016-12-07 2020-01-28 At&T Intellectual Property I, L.P. Method and apparatus for switching transmission mediums in a communication system
US10938108B2 (en) 2016-12-08 2021-03-02 At&T Intellectual Property I, L.P. Frequency selective multi-feed dielectric antenna system and methods for use therewith
US9911020B1 (en) 2016-12-08 2018-03-06 At&T Intellectual Property I, L.P. Method and apparatus for tracking via a radio frequency identification device
US10530505B2 (en) 2016-12-08 2020-01-07 At&T Intellectual Property I, L.P. Apparatus and methods for launching electromagnetic waves along a transmission medium
US10916969B2 (en) 2016-12-08 2021-02-09 At&T Intellectual Property I, L.P. Method and apparatus for providing power using an inductive coupling
US10601494B2 (en) 2016-12-08 2020-03-24 At&T Intellectual Property I, L.P. Dual-band communication device and method for use therewith
US10777873B2 (en) 2016-12-08 2020-09-15 At&T Intellectual Property I, L.P. Method and apparatus for mounting network devices
US10389037B2 (en) 2016-12-08 2019-08-20 At&T Intellectual Property I, L.P. Apparatus and methods for selecting sections of an antenna array and use therewith
US10411356B2 (en) 2016-12-08 2019-09-10 At&T Intellectual Property I, L.P. Apparatus and methods for selectively targeting communication devices with an antenna array
US10069535B2 (en) 2016-12-08 2018-09-04 At&T Intellectual Property I, L.P. Apparatus and methods for launching electromagnetic waves having a certain electric field structure
US9998870B1 (en) 2016-12-08 2018-06-12 At&T Intellectual Property I, L.P. Method and apparatus for proximity sensing
US10103422B2 (en) 2016-12-08 2018-10-16 At&T Intellectual Property I, L.P. Method and apparatus for mounting network devices
US10326689B2 (en) 2016-12-08 2019-06-18 At&T Intellectual Property I, L.P. Method and system for providing alternative communication paths
US9838896B1 (en) 2016-12-09 2017-12-05 At&T Intellectual Property I, L.P. Method and apparatus for assessing network coverage
US10340983B2 (en) 2016-12-09 2019-07-02 At&T Intellectual Property I, L.P. Method and apparatus for surveying remote sites via guided wave communications
US10264586B2 (en) 2016-12-09 2019-04-16 At&T Mobility Ii Llc Cloud-based packet controller and methods for use therewith
US9973940B1 (en) 2017-02-27 2018-05-15 At&T Intellectual Property I, L.P. Apparatus and methods for dynamic impedance matching of a guided wave launcher
US10298293B2 (en) 2017-03-13 2019-05-21 At&T Intellectual Property I, L.P. Apparatus of communication utilizing wireless network devices
US11833333B2 (en) 2017-07-12 2023-12-05 Insuline Medical Ltd Drug tracking device
KR20210087326A (en) 2020-01-02 2021-07-12 엘지이노텍 주식회사 Communication device for vehicle and method for controlling of the same
CN112216992A (en) * 2020-09-15 2021-01-12 南京航空航天大学 A Binary Frequency Reconfigurable Mean Line Antenna

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06224618A (en) * 1993-01-28 1994-08-12 Hitachi Ltd Self-impedance variable active antenna
JPH11163620A (en) * 1997-11-27 1999-06-18 Sharp Corp Frequency switching type antenna
US6069587A (en) 1998-05-15 2000-05-30 Hughes Electronics Corporation Multiband millimeterwave reconfigurable antenna using RF mem switches
US6662028B1 (en) * 2000-05-22 2003-12-09 Telefonaktiebolaget L.M. Ericsson Multiple frequency inverted-F antennas having multiple switchable feed points and wireless communicators incorporating the same
US6700540B2 (en) * 2002-02-14 2004-03-02 Ericsson, Inc. Antennas having multiple resonant frequency bands and wireless terminals incorporating the same
JP4346964B2 (en) 2003-06-09 2009-10-21 峰光電子株式会社 Multifrequency T-shaped antenna
JP2005150937A (en) * 2003-11-12 2005-06-09 Murata Mfg Co Ltd Antenna structure and communication apparatus provided with the same
JP3903991B2 (en) 2004-01-23 2007-04-11 ソニー株式会社 Antenna device
US7050018B2 (en) 2004-09-07 2006-05-23 Machine Applications Corp. Multi-band antenna system

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