EP2270925A1 - Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung - Google Patents

Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung Download PDF

Info

Publication number
EP2270925A1
EP2270925A1 EP09008751A EP09008751A EP2270925A1 EP 2270925 A1 EP2270925 A1 EP 2270925A1 EP 09008751 A EP09008751 A EP 09008751A EP 09008751 A EP09008751 A EP 09008751A EP 2270925 A1 EP2270925 A1 EP 2270925A1
Authority
EP
European Patent Office
Prior art keywords
frequency band
antenna device
port
low
selecting means
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.)
Withdrawn
Application number
EP09008751A
Other languages
English (en)
French (fr)
Inventor
Stefan Irmscher
Christian Braun
Johan Bäckman
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.)
Laird Technologies AB
Original Assignee
Laird Technologies AB
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 Laird Technologies AB filed Critical Laird Technologies AB
Priority to EP09008751A priority Critical patent/EP2270925A1/de
Publication of EP2270925A1 publication Critical patent/EP2270925A1/de
Withdrawn legal-status Critical Current

Links

Images

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
    • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • 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
    • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0421—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with a shorting wall or a shorting pin at one end of the element
    • 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
    • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
    • H01Q9/0442—Substantially flat resonant element parallel to ground plane, e.g. patch antenna with particular tuning means

Definitions

  • the present invention relates generally to antenna devices and more particularly to an antenna device for a portable radio communication device operable in at least a first high-frequency band and a second low-frequency band.
  • the invention also relates to a portable radio communication device comprising such an antenna device.
  • Internal antennas have been used for some time in portable radio communication devices. There are a number of advantages associated with the use of internal antennas, of which can be mentioned that they are small and light, making them suitable for applications wherein size and weight are of importance, such as in mobile phones.
  • one antenna device is to be used for communication in many such different frequency bands.
  • the radiating element is then to resonate in more than one frequency band.
  • a problem in prior art antenna devices is thus to provide a small sized multi-band antenna covering at least a high-frequency band and a low-frequency band while retaining good performance.
  • an antenna device In order for an antenna device to provide a broad bandwidth it should preferably comprise a radiating element without a ground plane, i.e. a so called off- ground antenna.
  • the antenna device due to limited space in a portable radio communication device the antenna device generally is required to have a radiating element positioned over, or at least partly over, a ground plane means, i.e. a so called on-ground antenna which limits the bandwidth it can cover.
  • a further problem with on-ground antennas, particularly for mobile phones, is that many times a so called bar phone has a length of about 90-100 mm, which is inappropriate for antenna operation around 900 MHz.
  • An object of the present invention is to provide an antenna device that covers at least a first high-frequency band and a low-frequency band while still keeping the overall size of the antenna device small and retaining good performance.
  • the invention is based on the realization that muliband coverage ability can be provided in a small sized antenna device operable in high and low frequency bands through modifying this antenna device by providing selection means for different feeding of low-frequency band operation and high-frequency band operation, respectively, wherein the antenna device is configured to operate as different antennas for high-frequency bands and low-frequency bands, respectively.
  • an antenna device as defined in claim 1.
  • the present invention provides an antenna device and a portable radio communication device, respectively, wherein the problem of providing an antenna device that covers at least a first high-frequency band and a low-frequency band while still keeping the overall size of the antenna device small and retaining good performance is solved through an antenna device for a portable radio communication device operable in at least a first high-frequency band and a second low-frequency band, the antenna device comprising: an on-ground radiating element having at least a first port for feeding of the first high-frequency band and a second port for feeding of the second low-frequency band; first selecting means connected to the first port, and second selecting means connected to the second port; the first selecting means is configured to open-end the first port and the second selecting means is configured to connect the second port to a second matching network through which the second low-frequency band is fed, when the antenna device operates in the second low-frequency band; and the second selecting means is configured to ground the second port and the first selecting means is configured to connect the first port to a first matching network through which the first high-frequency band is fed, when
  • the first selecting means comprises a first open-ended connection point and at least a second and a third connection point providing different matching networks for feeding of the multiple high-frequency bands.
  • the second selecting means comprises a first grounded connection point and at least a second and a third connection point providing different matching networks for feeding of the multiple low-frequency bands.
  • the radiating element preferably has a rectangular general outline, to improve the bandwidth by utilizing maximum volume for the antenna device.
  • the first and second selection means are preferably realized as:
  • the first and second selecting means are preferably provided as switches, to improve the bandwidth of the antenna device.
  • the antenna device preferably comprises a filter between the second port and ground, configured to pass the first high-frequency band and to block the second low-frequency band.
  • the first port is preferably connected at or near a top corner of the rectangular general outline of the radiating element to improve the bandwidth of the antenna device.
  • the first and second ports are connected to positions at the radiating element based on optimization of the Q0 factor for the first high-frequency band and the second low-frequency band.
  • Fig. 1 shows the outlines of an on-ground antenna device in a portable radio communication device, such as a mobile phone or similar device.
  • a radiating element 2 is arranged at the top of the portable radio communication device, over a ground plane means 1, such as the printed circuit board (PCB) thereof.
  • a ground plane means such as the printed circuit board (PCB) thereof.
  • the electrical connections to the radiating element 2 is in this embodiment on the top of the radiating element 2, but could less preferably be on the sides of the radiating element 2, on the bottom of the radiating element 2 or inside the outline of the radiating element 2.
  • the connection placement can be optimized for maximum bandwidth and can vary depending on size and shape of the radiating element.
  • On the PCB 1 there are provided RF circuitry and grounding devices (not shown) that are connectable to the antenna device of the invention.
  • the length extension of the portable radio communication device is illustrated by arrow 5 and the width extension of the portable radio communication device is illustrated by arrow 6.
  • the radiating element 2 is described as an on-ground radiating element it is not necessary for the radiating element 2 to be completely over the ground plane means 1. As long as at least a major portion of the radiating element is on-ground the negative effects mentioned above is evident.
  • Fig. 2 there is shown a general outline of the ground plane means 1 shown in Fig. 1 , on which the on-ground radiating element 2 is arranged in the top portion of the mobile phone.
  • Fig. 2 also illustrates first selecting means 7, a switching element, connected to the first port 3 and second selecting means 8, a switching element, connected to the second port 4, both selecting means with related matching components.
  • the first and second selecting means 7 and 8, together with their respective related matching components, are arranged on the PCB 1, but for clarity illustrated flattened out above the general outline of the mobile phone.
  • An advantage with providing selecting means on the antenna device is that a complete antenna module connectable to a PCB of a mobile phone is achieved.
  • the antenna device is operable in at least a first high-frequency band, e.g. covering GSM1800, GSM1900 and WCDMA, and a second low-frequency band, e.g. covering GSM850 and GSM900.
  • a first high-frequency band e.g. covering GSM1800, GSM1900 and WCDMA
  • a second low-frequency band e.g. covering GSM850 and GSM900.
  • the low-frequency band covers 824-960 MHz
  • the high-frequency band covers 1710-2170 MHz.
  • the antenna device comprises a single radiating element 2 having a first port 3 for feeding of the high-frequency band and a second port 4 for feeding the low-frequency band.
  • the antenna device utilizes available space efficiently by operating the radiating element 2 as a PIFA antenna, see Fig. 3 , for the high-frequency band and operating the radiating element 2 as a patch antenna, see Fig. 4 , for the low-frequency band.
  • the first port 3 is connected 9 to the RF circuitry through connection point P2, P3 or P4, and the second port 4 is connected to ground through connection point P5.
  • the first port 3 is open-ended through connection point P1 and the second port 4 is connected 10, through a connection separate from the high-frequency band feeding, to the RF circuitry through connection point P6, P7 or P8.
  • the three different connection points to RF circuitry for the first and second selecting means, respectively, represent different tuning and matching elements/networks for the antenna device for operation of high-frequency bands and low-frequency bands, respectively.
  • the different tuning elements/networks tune the radiating element to different centre frequencies for operation at different operating bands.
  • the antenna device is e.g.
  • connection point P2 configured to tune the radiating element 2 as a PIFA antenna for Gsy1800 operation
  • connection point P3 configured to tune the radiating element 2 as a PIFA antenna for GSM1900 operation
  • connection point P4 configured to tune the radiating element 2 as a PIFA antenna for WCDMA operation
  • connection point P6 configured to tune the radiating element 2 as a patch antenna for GSM850 operation
  • connection point P7 configured to tune the radiating element 2 as a patch antenna for GSM900 operation
  • connection point P8 configured to tune the radiating element 2 as a patch antenna for LTE operation.
  • the described selecting means are illustrated as switching elements having four switch positions.
  • the switching element is preferably a single pole, four- throw switching element (SP4T), for instance a GaAs FET device that is reflective in the off state.
  • SP4T single pole, four- throw switching element
  • the different connection points P2, P3, P4 and P6, P7, P8, respectively, defines, apart from dedicated tuning for different operating bands, different matching networks between the radiating element and the RF circuitry of the portable radio communication device, such that the antenna device can be optimized for a plurality of high-frequency bands and a plurality of low-frequency bands, all utilizing a PIFA structure for the high-frequency bands and a patch structure for the low-frequency bands.
  • three different tuning and matching networks have been' described for each selecting means 7 and 8, fewer or more running and matching networks might be used for operation of fewer or more frequency bands.
  • the matching elements preferably match the connections to the RF circuitry to 50 ⁇ .
  • the matching and reactive elements are preferably provided as components. These can be lumped components attached to the antenna structure of the antenna device, for instance through soldering to the corresponding contact pads.
  • The, distance between the first port 3 and the second port 4, as well as their respective position on the radiating element 2 is optimized for the high-frequency band and low-frequency band operation by means of the total best bandwidth, which in turn is calculated by means of Q0 calculations.
  • This calculation also considers the dimensions of the radiating element, such that they provide fundamental resonance in the first high-frequency band and in the second low-frequency band.
  • Q0 represents the quality factor of the antenna at resonance (i.e., the antenna is tuned to zero reactance).
  • the quality factor of an antenna relates the power stored in the reactive field to the radiated power.
  • the bandwidth defined for a certain return loss or voltage-standing-wave-ratio (VSWR) is inversely proportional to Q.
  • Fig. 5 shows the Q0 factor for the antenna device in dependence of frequency in GHz.
  • a first curve LB1 shows the Q0 factor for low-frequency operation for an antenna device having a radiating element primarily sized for high-frequency band operation.
  • a second curve LB2 shows the Q0 factor for low-frequency operation for an antenna device having a radiating element primarily sized for low-frequency band operation.
  • a third curve HB1 shows the Q0 factor for high-frequency operation for an antenna device having a radiating element primarily sized for high-frequency band operation.
  • a fourth curve HB2 shows the Q0 factor for high-frequency operation for an antenna device having a radiating element primarily sized for low-frequency band operation.
  • the optimal bandwidth for low-frequency band operation is provided in the dashed region of LB, and the optimal bandwidth for high-frequency band operation is provided in the dashed region of HB.
  • the antenna device can work both in the LB and HB region.
  • the best bandwidth for the antenna device is achieved with optimization of the distance between the first port 3 and the second port 4 and the position of the first port 3 and the second port 4 on the radiating element.
  • the first port 3, for high-frequency band operation is preferably positioned on the top edge of the radiating element 2, close to the side of the radiating element 2. This optimization is based on numerical analysis for thousands of variations.
  • the bandwidth of the antenna device increases for a wider radiating element, wherein a mobile phone typically having a width of about 40 mm, thereby creating a maximum width of the radiating element.
  • the bandwidth of the antenna device is optimized for a radiating element having a length of about 15-20 mm, wherein a shorter radiating element decreases the bandwidth and a longer radiating element also decreases the bandwidth.
  • the radiating element have been shown as having a rectangular-shaped general outline to provide broad bandwidth for both the first high-frequency band and the second low-frequency band, but different shapes of the radiating elements as well as added slots and similar modification is foreseen to fine tune the antenna device or to add further frequency bands.
  • the first selecting means is operated for varying matching of the radiating element in the first high-frequency bands while the second selecting means is grounded.
  • the first selecting means is open-ended while the second selecting means varies matching of the radiating element in the second low-frequency bands.
  • the radiating element has been described as an on-ground radiating element the inventive principle can be applied also for off-ground radiating elements, wherein the radiating element would operate as a monopole antenna for low-frequency bands and as an IFA for high-frequency bands.
  • FIG. 6 An antenna device according to a second embodiment of the present invention will now be described with reference to Fig. 6 .
  • the second embodiment is identical to the first embodiment described above, apart from the following.
  • the first and second selecting means 7 and 8 are configured as SP3T switches'.
  • the first selecting means 7 is configured for open-end in P1, GSM1800 and GSM1900 in P2 and WCDMA in P3.
  • the second selecting means 8 is configured for grounding in P5, GSM850 in P6 and GSM900 in P7. Further, in order to reduce switch losses, an inductor is arranged in parallel with the switch 8.
  • the third embodiment is identical to the first embodiment described above, apart from the following.
  • the first and second selecting means 7 and 8 are configured as filtering means.
  • the open-ended function for port 3, during low-frequency band operation can e.g. be provided by a two-pole filter combined with a high-frequency band matching net connected to ground.
  • the grounding function for port 4, during high-frequency band operation can e.g. be provided by a two-pole filter combined with a low-frequency band matching net connected to ground.
  • An antenna device according to the third embodiment of the present invention can be combined with an antenna device according to the second embodiment of the present invention, which is illustrated in Fig. 8 .
  • Filtering means 13 is connected between first switching means 7 and the radiating element 2, and is configure to block low-frequency bands and to pass high-frequency bands. In this way also the first switching means can be bypassed by an inductor, reducing switching loss, at the same time providing an open-ended circuit for the low-frequency band.
  • Filtering means 13 is e.g. realized by a 5 pF capacitor in parallel with a 6 nH inductor. Several similar stages can be cascaded for better performance of the filtering means 13.

Landscapes

  • Support Of Aerials (AREA)
EP09008751A 2009-07-03 2009-07-03 Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung Withdrawn EP2270925A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP09008751A EP2270925A1 (de) 2009-07-03 2009-07-03 Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP09008751A EP2270925A1 (de) 2009-07-03 2009-07-03 Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung

Publications (1)

Publication Number Publication Date
EP2270925A1 true EP2270925A1 (de) 2011-01-05

Family

ID=40910973

Family Applications (1)

Application Number Title Priority Date Filing Date
EP09008751A Withdrawn EP2270925A1 (de) 2009-07-03 2009-07-03 Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung

Country Status (1)

Country Link
EP (1) EP2270925A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104176823A (zh) * 2014-07-09 2014-12-03 浙江大学 集废水生物处理与促进甲烷回收于一体的微生物电解系统及方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0892459A1 (de) * 1997-07-08 1999-01-20 Nokia Mobile Phones Ltd. Doppelresonanzantennenstruktur für mehrere Frequenzbereiche
WO2003096474A1 (en) * 2002-05-08 2003-11-20 Sony Ericsson Mobile Communications Ab Multiple frequency bands switchable antenna for portable terminals
EP1398875A1 (de) * 2002-09-12 2004-03-17 Filtronic LK Oy System zur Kontrolle der Sendeleistung einer Mehrbandantenne

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0892459A1 (de) * 1997-07-08 1999-01-20 Nokia Mobile Phones Ltd. Doppelresonanzantennenstruktur für mehrere Frequenzbereiche
WO2003096474A1 (en) * 2002-05-08 2003-11-20 Sony Ericsson Mobile Communications Ab Multiple frequency bands switchable antenna for portable terminals
EP1398875A1 (de) * 2002-09-12 2004-03-17 Filtronic LK Oy System zur Kontrolle der Sendeleistung einer Mehrbandantenne

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104176823A (zh) * 2014-07-09 2014-12-03 浙江大学 集废水生物处理与促进甲烷回收于一体的微生物电解系统及方法
CN104176823B (zh) * 2014-07-09 2016-08-24 浙江大学 集废水生物处理与促进甲烷回收于一体的微生物电解系统及方法

Similar Documents

Publication Publication Date Title
US6650295B2 (en) Tunable antenna for wireless communication terminals
KR100993439B1 (ko) 안테나 장치 및 무선 통신 장치
EP1790034B1 (de) Antenneneinrichtung und tragbares funkkommunikationsgerät mit einer solchen antenneneinrichtung
EP2628209B1 (de) Eine rahmenantenne für mobilteile und andere anwendungen
US9761951B2 (en) Adjustable antenna apparatus and methods
US7205942B2 (en) Multi-band antenna arrangement
US7274340B2 (en) Quad-band coupling element antenna structure
CN109193153B (zh) 天线系统、方法以及移动通信装置
US7505006B2 (en) Antenna arrangement
CN111029729A (zh) 天线组件及电子设备
EP2139067A1 (de) Multiband-Antenne und Funkkommunikationsendgerät
KR100756312B1 (ko) 공진주파수 및 입력 임피던스 조절 가능한 다중 대역내장형 안테나
WO2008010149A1 (en) Antenna with reduced sensitivity to user finger position
WO2010120218A1 (en) Multiband antenna device and portable radio communication device comprising such an antenna device
KR20070051292A (ko) 안테나 장치 및 그러한 안테나 장치를 포함하는 휴대무선통신 장치
Ghaffar et al. Dual frequency band and polarization reconfigurable antenna for mobile devices
CN204577588U (zh) 应用于平板电脑的天线和平板电脑
EP2270925A1 (de) Antennenvorrichtung und tragbare Funkkommunikationsvorrichtung mit einer solchen Antennenvorrichtung
Shameem et al. A low profile penta-band antenna for portable devices
Liang et al. Varactor loaded tunable printed PIFA
Yoon et al. A frequency-selecting technique for mobile handset antennas based on capacitance switching
Anguera et al. Compact multiband antenna system for smartphone platforms
Pokorný Tunable dual-band antenna for agile communication handsets
Wu et al. A folded loop antenna with four resonant modes
Kashiwagi et al. Dual-band bent-folded-monopole antenna

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

AX Request for extension of the european patent

Extension state: AL BA RS

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20110706