EP0350006A2 - Antennenstruktur für ein tragbares Radiogerät - Google Patents

Antennenstruktur für ein tragbares Radiogerät Download PDF

Info

Publication number
EP0350006A2
EP0350006A2 EP89112272A EP89112272A EP0350006A2 EP 0350006 A2 EP0350006 A2 EP 0350006A2 EP 89112272 A EP89112272 A EP 89112272A EP 89112272 A EP89112272 A EP 89112272A EP 0350006 A2 EP0350006 A2 EP 0350006A2
Authority
EP
European Patent Office
Prior art keywords
antenna
conductor
battery
loop antenna
radio device
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.)
Granted
Application number
EP89112272A
Other languages
English (en)
French (fr)
Other versions
EP0350006A3 (en
EP0350006B1 (de
Inventor
Takashi Oda
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.)
NEC Corp
Original Assignee
NEC Corp
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 NEC Corp filed Critical NEC Corp
Publication of EP0350006A2 publication Critical patent/EP0350006A2/de
Publication of EP0350006A3 publication Critical patent/EP0350006A3/en
Application granted granted Critical
Publication of EP0350006B1 publication Critical patent/EP0350006B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/29—Combinations of different interacting antenna units for giving a desired directional characteristic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/27—Adaptation for use in or on movable bodies
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Definitions

  • the present invention relates to an antenna structure used in a portable radio device and, more particularly, to an antenna structure suitable for a portable radio device operating in a UHF ultra high frequency) band.
  • a loop antenna has been employed in a portable radio device, such as a paging receiver, for its compactness.
  • the loop antenna has strong directivity.
  • the radio device is held so that the loop antenna is in the direction of minimum sensitivity, the signal reception sensitivity will be deteriorated. This problem will be discussed herein referring to the accompanying drawings.
  • An object of the present invention is, therefore, to provide a generally improved antenna structure which eliminates the above-mentioned problems.
  • Another object of the present invention is to provide an antenna structure suitable for a portable radio device.
  • Yet another object of the present invention is to provide an antenna structure having good directivity.
  • Still yet another object of the present invention is to provide an antenna structure having a loop antenna and a supplemental antenna which structure is compact while having a high antenna gain even if the loop antenna is positioned to have a minimum gain.
  • an antenna structure comprising a loop antenna electrically connected to a high-frequency circuit of a portable radio device.
  • the antenna structure also comprises a supplemental antenna including a coil spring which is used for fixing a dry battery powering the portable radio device, and a negative cylindrical conductor of the dry battery which conductor is electrically connected with the coil spring.
  • the coil spring is placed to be inductively coupled to the loop antenna.
  • the axis line of the dry battery is substantially perpendicular to a plane including the loop antenna.
  • the radio paging receiver includes a housing 1 accommodating communication circuitry 2, a loop antenna 3, a connecting pattern 3a, a dry battery 4 and a printed circuit board 5.
  • the loop antenna 3 is mounted on the printed circuit board 5 and electrically connected through the connecting pattern 3a to the communication circuitry 2.
  • the loop antenna 3 Since the loop antenna 3 has strong directivity, it is mounted on the board 5 so that the antenna 3 has a maximum gain with respect to a vertical polarized wave A in a standard use condition shown in Fig. 2A.
  • the antenna gain is extremely deteriorated and thus the signal reception sensitivity is decreased, as mentioned earlier.
  • Fig. 3 shows the horizontal paging sensitivity characteristics of loop antenna shown in Figs. 1, 2A and 2B.
  • the gain characteristics were obtained for a prior art antenna 1 mounted on a paging receiver and receiving a signal of 900 MHz.
  • the solid line A1 indicates horizontal sensitivity in free space for the condition of Fig. 2A.
  • Dotted line B1 indicates horizontal sensitivity in free space for the condition of Fig. 2B.
  • the sensitivity indicated by the dotted line B1 is deteriorated in all directions, compared with the sensitivity indicated by the solid line A1.
  • the prior art antenna structure shown in Figs. 1. 2A and 2B is not suitable for a portable radio device, such as a paging receiver.
  • Fig. 4 shows a block diagram of a paging receiver embodying the present invention.
  • a loop antenna 61 picks up a radio signal and supplies it to a receiver section 62.
  • the receiver section 62 amplifies, frequency converts and demodulates the radio signal to produce a demodulated baseband signal.
  • the baseband signal is supplied to a decoder 63 at which the baseband signal is wave shaped and compared with a paging number assigned to the paging receiver and stored therein. If the baseband signal contains a paging number identical with the stored paging number, the decoder 63 will produce an alert signal.
  • a driver 64 drives a speaker 65 to generate an alert sound, so that the user is informed of being paged.
  • the driver 64 and the speaker 65 may constitute an annunciator means.
  • a battery 66 applies power through a line 69 to the receiver section 62, decored 63 and driver 64.
  • the positive terminal 66a of battery 66 is connected through a capacitor 68 to common potential.
  • the negative terminal 66b of the battery is connected to the common potential through a coil spring 67.
  • the negative terminal 66b and the coil spring 67 constitute a supplemental antenna which is inductively coupled to the loop antenna 61.
  • a radio signal picked up by the supplemental antenna (66b, 67) is supplied to the loop antenna 61 and then to the receiver section 62.
  • the supplemental antenna is arranged to compensate deterioration in the antenna gain due to the directivity of the loop antenna 61.
  • a radio signal picked up by the loop antenna 61 and by the supplemental antenna (66b, 67) is applied to a base of a high-frequency transistor amplifier 73 through a resonance matching circuit composed of a variable capacitor 70 and a capacitor 71.
  • the variable capacitor 70 is connected between the loop antenna 61 and the common potential.
  • the capacitor 71 is connected between the loop antenna 61 and the base of transistor 73.
  • the common-emitter transistor 73 amplifies the radio signal and supplies the amplified signal to a frequency converter within the radio section 62.
  • a resistor 75 is inserted between the base of transistor 73 and the battery 66.
  • a capacitor 76 is inserted between the base of the transistor 73 and the common potential.
  • a resistor 72 is a bias resistor of transistor 73.
  • a pattern inductance element 74 is of a collector load of transistor 73.
  • the measured impedance is plotted on the Smith chart of Fig. 6.
  • the measured impedance does not change even if the positive terminal 66a is opened, i.e., the capacitor 68 and the line 69 are eliminated from the battery 66. In other words, the measured impedance is dominated by the negative terminal 66b and coil spring 67 and not affected by the positive side circuitry of battery 66.
  • the supplemental antenna By inductively coupling the supplemental antenna (66b, 67) to the loop antenna 61, a high-frequency power induced on the supplemental antenna is passed to the loop antenna 61 and then to the transistor amplifier 73. Furthermore, by making the supplemental antenna intersect perpendicularly to a plane including the loop antenna 61, the supplemental antenna compensates for deterioration in the signal reception sensitivity caused by the directivity of the loop antenna 61.
  • a housing 11 and communication circuitry 12 are indicated by an imaginary line and a dotter line, respectively.
  • the circuitry 12 may include the receiver section 62, the decoder 63, the driver 64 and the speaker 65 shown in Fig. 4.
  • a loop antenna 13 is composed of a substantially loop shaped conductor.
  • the loop antenna 13 is connected with a common potential pattern 12a through a conductive pattern 13a of printed circuit board 15 and corresponds to the loop antenna 61 of Figs. 4 and 5.
  • a coil spring, or helical conductor, 16 is in contact with the negative terminal 14b of a dry battery 14 whose cylindrical conductor 14c has the same potential as the negative terminal 14b.
  • the other end of coil spring 16 is connected with the negative terminal projection 17 which in turn is connected with the the common potential pattern 12a through a conductive pattern 14a.
  • the coil spring 16 and the battery negative terminal 14b and 14c constitute a supplemental antenna corresponding to the supplemental antenna (66b, 67) of Figs. 4 and 5.
  • the combined lengths of the battery 14 and the coil spring 16 is set equal to one quarter of a wavelength used.
  • the supplemental antenna constitutes a base-loaded antenna whose electrical length is increased by the addition of loading coil (16) in series with the antenna (14b) at the common potential.
  • the combined lengths may instead be set to an odd multiple of one quarter of the used wavelength. It is, however, not desirable to set the combined lengths to a value other than one quarter of the wavelength, because the longer the combined lengths becomes, the more bulky the antenna structure.
  • the supplemental antenna having the coil spring 16 and the cylindrical battery conductor 14c is substantially perpendicular to a plane including the loop antenna 13 and substantially along a line intersecting perpendicularly the center of the loop of loop antenna 13.
  • the axis line of the battery substantially perpendicularly intersects the center of the loop of loop antenna 13.
  • the supplemental antenna operates as a main antenna and induces maximum power while the loop antenna 13 induces minimum power. Since the supplemental antenna, especially the loading coil 16, is inductively coupled to the loop antenna 13, no deterioration in the signal reception sensitivity occurs even if the loop antenna 13 is placed to induce minimum power.
  • Fig. 9 the horizontal paging sensitivity embodying the present invention in free space are shown.
  • the plot of Fig. 9 is obtained using an antenna according to this invention mounted on a paging receiver and receiving a signal at a frequency of 900 MHz.
  • Solid line A2 indicates a horizontal sensitivity measured for the paging receiver placed as shown in Fig. 8A.
  • Dotter line B2 indicates a horizontal sensitivity measured for the paging receiver placed as shown in Fig. 8B. Because of the supplemental antenna, no deterioration in either cases occurs.
  • the present antenna (Fig. 7) has been determined to have a gain of -10 dB relative to a half-wave dipole while the prior art antenna (Fig. 1) has a gain of -30 dB relative to a half-wave dipole.
  • the antenna gain of about 20 dB can be improved according to the present invention.
  • the wavelength at 900 MHz is about 33.3 centimeters one quarter of which is around 8.3 centimeters.
  • the length of the negative cylindrical conductor of the dry battery is about 4.2 centimeters.
  • the effective length of the coil spring 16 is around 4.0 centimeters.
  • One end of the coil spring is in contact with the negative terminal 14b of the battery. This contact portion of the coil spring does not contribute to its effective length.
  • the portion other than the contact portion should be made as thick as possible to reduce the inductance.
  • the antenna structure has a supplemental antenna inductively coupling to the loop antenna and including a coil spring and the battery negative cylindrical conductor which is perpendicularly to a plane including the loop antenna.

Landscapes

  • Support Of Aerials (AREA)
EP19890112272 1988-07-05 1989-07-05 Antennenstruktur für ein tragbares Radiogerät Expired - Lifetime EP0350006B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP168175/88 1988-07-05
JP16817588 1988-07-05

Publications (3)

Publication Number Publication Date
EP0350006A2 true EP0350006A2 (de) 1990-01-10
EP0350006A3 EP0350006A3 (en) 1990-10-24
EP0350006B1 EP0350006B1 (de) 1994-05-18

Family

ID=15863186

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890112272 Expired - Lifetime EP0350006B1 (de) 1988-07-05 1989-07-05 Antennenstruktur für ein tragbares Radiogerät

Country Status (7)

Country Link
EP (1) EP0350006B1 (de)
JP (1) JPH0812970B2 (de)
KR (1) KR920007133B1 (de)
AU (1) AU625874B2 (de)
CA (1) CA1328310C (de)
DE (1) DE68915347T2 (de)
HK (1) HK131194A (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0415703A1 (de) * 1989-08-29 1991-03-06 Nec Corporation Antennensystem für tragbares Funkgerät
US5255001A (en) * 1989-08-29 1993-10-19 Nec Corporation Antenna system for portable radio apparatus
EP0689301A1 (de) * 1994-06-24 1995-12-27 Telediffusion De France Rundstrahlantennensystem mit Polarisationsdiversität und Winkeldiversität
EP0701297A1 (de) * 1994-09-09 1996-03-13 Telediffusion De France Mehrfach polarisiertes Sende-Empfangsantennensystem mit Rundstrahlcharakteristik
EP0783190A1 (de) * 1996-01-02 1997-07-09 Texas Instruments Deutschland Gmbh Passive x-y-z Antenne für ein Antwortsendegerät

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5613589B2 (ja) * 2010-03-19 2014-10-29 パナソニック株式会社 無線機

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1056673B (de) * 1957-04-26 1959-05-06 Marconi Wireless Telegraph Co Zirkularpolarisierte Antennenanordnung
JPS562707A (en) * 1979-06-21 1981-01-13 Tdk Corp Antenna
DE3100313A1 (de) * 1981-01-08 1982-08-12 Müllerschön, Wolfgang, 7441 Altenriet Doppelrahmenantenne mit teleskopstab und kombination von zwei doppelrahmenantennen mit jeweiligem teleskopstab
JPS61123303A (ja) * 1984-11-20 1986-06-11 Matsushita Electric Ind Co Ltd 小形無線機のアンテナ

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2841358B2 (ja) * 1986-05-16 1998-12-24 日本電気株式会社 補助アンテナ
JPS62196432U (de) * 1986-06-03 1987-12-14
JP2624257B2 (ja) * 1987-06-29 1997-06-25 日本電気株式会社 無線機用アンテナ

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1056673B (de) * 1957-04-26 1959-05-06 Marconi Wireless Telegraph Co Zirkularpolarisierte Antennenanordnung
JPS562707A (en) * 1979-06-21 1981-01-13 Tdk Corp Antenna
DE3100313A1 (de) * 1981-01-08 1982-08-12 Müllerschön, Wolfgang, 7441 Altenriet Doppelrahmenantenne mit teleskopstab und kombination von zwei doppelrahmenantennen mit jeweiligem teleskopstab
JPS61123303A (ja) * 1984-11-20 1986-06-11 Matsushita Electric Ind Co Ltd 小形無線機のアンテナ

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, vol. 10, no. 313 (E-448)[2369], 24th October 1986; & JP-A-61 123 303 (MATSUSHITA ELECTRIC IND. CO., LTD) 11-06-1986 *
PATENT ABSTRACTS OF JAPAN, vol. 5, no. 51 (E-51)[723], 10th April 1981; & JP-A-56 002 707 (TOKYO DENKI KAGAKU KOGYO K.K.) 13-01-1981 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0415703A1 (de) * 1989-08-29 1991-03-06 Nec Corporation Antennensystem für tragbares Funkgerät
US5255001A (en) * 1989-08-29 1993-10-19 Nec Corporation Antenna system for portable radio apparatus
EP0689301A1 (de) * 1994-06-24 1995-12-27 Telediffusion De France Rundstrahlantennensystem mit Polarisationsdiversität und Winkeldiversität
FR2721756A1 (fr) * 1994-06-24 1995-12-29 Telediffusion Fse Système d'antennes d'émission-réception omnidirectionnel à diversité angulaire et de polarisation.
EP0701297A1 (de) * 1994-09-09 1996-03-13 Telediffusion De France Mehrfach polarisiertes Sende-Empfangsantennensystem mit Rundstrahlcharakteristik
EP0783190A1 (de) * 1996-01-02 1997-07-09 Texas Instruments Deutschland Gmbh Passive x-y-z Antenne für ein Antwortsendegerät

Also Published As

Publication number Publication date
DE68915347T2 (de) 1994-08-25
AU625874B2 (en) 1992-07-16
EP0350006A3 (en) 1990-10-24
HK131194A (en) 1994-12-02
CA1328310C (en) 1994-04-05
EP0350006B1 (de) 1994-05-18
JPH0812970B2 (ja) 1996-02-07
AU3790089A (en) 1990-01-11
KR920007133B1 (en) 1992-08-27
JPH02124604A (ja) 1990-05-11
DE68915347D1 (de) 1994-06-23

Similar Documents

Publication Publication Date Title
US5227804A (en) Antenna structure used in portable radio device
US6154177A (en) Antenna device and radio receiver using the same
JP2809365B2 (ja) 携帯無線機
JP3114621B2 (ja) 表面実装型アンテナおよびこれを用いた通信機
JP3279205B2 (ja) 表面実装型アンテナおよび通信機
US7039437B2 (en) Internal broadcast reception system for mobile phones
JP3523670B2 (ja) 携帯電話機用の挿脱自在形広帯域アンテナ
EP0334297A2 (de) Am Handgelenk zu tragendes drahtloses Gerät
KR100587276B1 (ko) 휴대 전화기 및 휴대 전화기의 밧데리
EP0350006B1 (de) Antennenstruktur für ein tragbares Radiogerät
EP0817312A2 (de) Antenne
JPH1032413A (ja) 表面実装型アンテナ
US4626862A (en) Antenna having coaxial driven element with grounded center conductor
JP3431379B2 (ja) アンテナ
JPH11163757A (ja) アンテナ及びアンテナ回路
JP3034032U (ja) ループアンテナ及びそれを用いた通信端末着信通知装置
JPH066586Y2 (ja) 外部補助アンテナ
JP3204631B2 (ja) 車載用アンテナ
JPH066585Y2 (ja) 小型アンテナ
JP3904957B2 (ja) 携帯電話機のデュアルバンド用アンテナ構造
EP0213743B1 (de) Kraftfahrzeugantennensystem
JP2824478B2 (ja) 手首装着形無線装置
JP2001185949A (ja) デュアルモードアンテナ
JPH0567910A (ja) 携帯可能な無線装置
JPH11308038A (ja) アンテナおよびアンテナ装置

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

17P Request for examination filed

Effective date: 19890802

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE GB NL

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE GB NL

17Q First examination report despatched

Effective date: 19921218

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE GB NL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19940518

REF Corresponds to:

Ref document number: 68915347

Country of ref document: DE

Date of ref document: 19940623

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20000703

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20000705

Year of fee payment: 12

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20010705

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20010705

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20020501