EP0560503B1 - Elektrisches Filter - Google Patents

Elektrisches Filter Download PDF

Info

Publication number
EP0560503B1
EP0560503B1 EP93301243A EP93301243A EP0560503B1 EP 0560503 B1 EP0560503 B1 EP 0560503B1 EP 93301243 A EP93301243 A EP 93301243A EP 93301243 A EP93301243 A EP 93301243A EP 0560503 B1 EP0560503 B1 EP 0560503B1
Authority
EP
European Patent Office
Prior art keywords
filter
directional coupler
transmitter
transmission line
transmission
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.)
Expired - Lifetime
Application number
EP93301243A
Other languages
English (en)
French (fr)
Other versions
EP0560503A1 (de
Inventor
Seppo Yrjölä
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.)
Pulse Finland Oy
Original Assignee
LK Products Oy
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 LK Products Oy filed Critical LK Products Oy
Publication of EP0560503A1 publication Critical patent/EP0560503A1/de
Application granted granted Critical
Publication of EP0560503B1 publication Critical patent/EP0560503B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/12—Coupling devices having more than two ports
    • H01P5/16—Conjugate devices, i.e. devices having at least one port decoupled from one other port
    • H01P5/18—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers

Definitions

  • the present invention relates to a filter.
  • High frequency components of radio telephones constitute an exception to this trend.
  • High frequency components have to date been extremely complex in construction, comprising discrete components and strip constructions.
  • an output control circuit for controlling the output level of the transmission.
  • the operation of the output control circuit is based on indications of the output level of the transmitter and comparison with a reference value.
  • An essential part of the output control circuit is formed by a directional coupler, placed immediately adjacent the separation filter of the reception circuit, with which a voltage comparable with the output of the transmitter is produced.
  • the directional coupler is therefore used for measuring the transmission output power, whereby the output level is controlled with the output control circuit.
  • the directional coupler is usually located after the transmitter or before the antenna.
  • the directional coupler is conventionally constructed using various coupled transmission line constructions and transformers.
  • a widely used directional coupler having low manufacturing costs, can be constructed using microstrips or strip lines mounted directly on a telephone circuit board.
  • Drawbacks of the structure include the relatively large circuit board area required and the high dependence of the operation on the properties of the circuit board substrate material and variations therein.
  • the substrate material affects the dielectric insulation material losses of the microstrip line, these being greatly dependent on the so-called loss tangent of the material, and it affects the line losses, which are affected by the smoothness of the surface of the material.
  • an advantageous general purpose material is frequently selected for the substrate material in radio telephones.
  • the use of such a material causes deterioration in the functioning of the directional coupler constructed thereon.
  • the increased material losses of the substrate material and the tolerances of the properties can be directly detected in the insertion attenuation of the directional coupler and in the variation of said properties.
  • US 3,829,770 discloses a directional coupler which has couplers in the form of conductive strips secured to an insulative board and spaced from a primary line conductive strip.
  • US 4,433,314 discloses a suspended substrate multiplexer which has four channel dropping sections. Each of these comprises a two 90° hybrid couplers connected by a pair of bandpass filters.
  • GB 2261325 A which has an earlier priority date than the present application but was published after the filing of the present application, discloses a ceramic filter which carries a directional coupler. With reference to GB 2261325 A the applicant has voluntarily limited the scope of the present application in respect of the United Kingdom by submitting separate claims for the United Kingdom.
  • An advantage of the present invention is the avoidance of the above mentioned drawbacks by removing the directional coupler from the substrate of the transmitter as a discrete component or strip structure and by forming the directional coupler as an integral part of the filter.
  • a filter in accordance with the present invention makes use of transmission lines in the couplings of the filter, such as a receiver (RX) or a transmitter (TX) separation filter, or in the matching circuits for implementing the directional coupler.
  • the directional coupler can be transferred from the circuit board substrate, frequently being a high-loss substrate and afflicted by environmental disturbances, into a high frequency filter.
  • the high frequency filter offers an encapsulated environment protected against interference with a low-loss and stable substrate as required by a filter.
  • the directional coupler in accordance with the invention comprises a transmission line of a filter and a switch transmission line coupled thereto, the only additional losses caused by the coupler are of the magnitude of the output sample sampled by the transmitter system, which is a significant improvement in comparison with the state of the art.
  • the directional coupler in accordance with the invention is relatively easy to implement by placing the coupler in conjunction with the filter or by making use of the components existing in the filter, such as coupling lines or impedance matching transmission lines.
  • the directional coupler can be produced by adding another microstrip e.g. in parallel with a microstrip.
  • the directional coupler may, in fact, be implemented in a great number of ways using many types of transmission lines, preferably microstrips, or suspended substrate lines.
  • the manner of implementation may vary in accordance with the invention, but the essential feature is that a directional coupler is included in the filter.
  • the directional coupler is implemented with the existing filter constructions.
  • a radio apparatus which is provided with both a transmitter and a receiver and in which the same antenna is used needs a transmission network for directing the signal to be transmitted and signal received appropriately.
  • the signal from the antenna must be directed to the receiver so that no significant interference is caused by the transmitter. Similarly, a signal from the transmitter must be transmitted to the antenna without causing any interference from the receiver.
  • duplex filters composed of two separation filters and based on resonators are used to separate the signals to be transmitted and received.
  • the duplex filter is therefore usually composed of two separate bandpass filters, one of them being connected to the receiver branch, its mean frequency and bandwidth corresponding to the receiving band, and the other filter being connected to the transmitter branch, its mean frequency and bandwidth corresponding to the transmission band.
  • the other ends of the filters have frequently been connected to a common antenna line via a transmission line matching the impedance.
  • the duplex filter has frequently been accommodated within a single housing provided with terminals for transmitter, receiver and antenna, in practice it is composed of two separate bandpass filters because the isolation between the filters must be made as great as possible so that the electromagnetic leakages therebetween should not impede the functioning of the filter.
  • the filters constructed using the helix technique are provided with a metal partition between both of the filters, with which the required isolation is efficiently implemented.
  • the couplings in duplex filters to the resonators and the couplings between the resonators have commonly been implemented by means of matching couplings formed by various transmission line constructions and discrete components.
  • FIG. 1 is a schematic diagram of a filter comprising a filter-directional coupler block in accordance with the invention.
  • the figure shows schematically the coupling of a duplex filter 1 of a radio telephone to a transmitter block 4 and a receiver block 5.
  • the duplex filter 1 comprises four ports: one port 8 for a transmission signal entering the filter, a port 9 for the antenna, a port (not shown) for the receiver 5, and a directional coupler port 7.
  • a signal from the antenna 6 to be received propagates via the reception filter block 3 of the duplex filter 1 to the receiver 5.
  • a signal from the transmitter 4 propagates through the receiver (RX) separation filter block 2 of the duplex filter 1 to antenna 6.
  • the directional coupler 10 takes a sample of a given level, comparable with the output level of the transmitter, and transmits it to the directional coupler port 7.
  • the figure illustrates the integration of a directional coupler 10 in the matching circuit at the transmitter end of the RX separation filter 2 of the duplex filter 1.
  • the directional coupler 10 has preferably been implemented on a circuit board using coupled microstrips.
  • One of the strips, strip A serves as a coupling strip for the filter input to the helix HX1
  • the other one of the strips, strip B serves as a coupling strip to the directional coupler port 7.
  • the coupler strip B ends in a resistor R.
  • the directional coupler could be positioned adjacent the antenna port 9, whereby it could be easily implemented by adding another branch next to strip C which carries out the impedance matching.
  • the additional branch would comprise a directional coupler port 7, a coupler transmission line, comparable to line B, and an end resistor R.
  • the directional coupler 10 is preferably composed of two adjacent microstrips A and B provided with common ground planes. Electromagnetic coupling exists between the strips: a voltage in one strip producing an electric field which induces a voltage also in the other strip. Magnetic coupling is likewise caused by a magnetic field provided by the current propagating in the strip, said field inducing a current also into the other strip.
  • the desired part of the power which is determined by the coupling, is coupled to the directional coupler port 7, another part thereof passes through the coupler 10 towards a first resonator HX1 of the filter, and a very small leakage part caused by the non-homogeneity and quasi transverse electric and magnetic (TEM) waveform of the switch is short circuited via the end resistor R to the ground.
  • the microstrip coupler 10 described above is bilateral, i.e. any power carried to any port will be coupled in the same way, because of the symmetry.
  • the proportions of the quasi TEM directional waveform in the coupler is generally used as a quality measure. In other words comparison of the power at directional coupler port 7 and the power at the insulated leakage port leading to ground via resistor R provides a measure of quality.

Claims (7)

  1. Filtereinheit (2), enthaltend:
    Filtermittel (HX1-4), die mit Impedanz-Anpassungsmitteln (C) gekoppelt sind; und
    Kopplungsmittel (7,8,9,A) zur Kopplung der Filtermittel mit externen Komponenten, wobei die Kopplungsmittel eine erste Übertragungsleitung (A) enthalten; gekennzeichnet durch einen Richtungskoppler (10), der durch eine zur ersten Übertragungsleitung benachbarte zweite Übertragungsleitung (B) gebildet ist, um das von der ersten Übertragungsleitung übertragene Signal abzutasten und ein korrespondierendes Ausgangssignal zur Verfügung zu stellen.
  2. Filtereinheit nach Anspruch 1, wobei eine der Übertragungsleitungen als Impedanzanpassungs-Übertragungsleitung (C) ausgebildet ist.
  3. Filtereinheit nach Anspruch 1 oder 2, wobei die Übertragungsleitungen als Mikrostreifen ausgebildet sind.
  4. Filtereinheit nach Anspruch 1 oder 2, wobei die Übertragungsleitungen als Substrathängeleitungen ausgebildet sind.
  5. Filtereinheit nach irgendeinem der vorangegangenen Ansprüche, wobei das Filter als Helixfilter ausgebildet ist.
  6. Filtereinheit nach irgendeinem der Ansprüche 1 bis 4, wobei das Filter als Keramikfilter ausgebildet ist.
  7. Filtereinheit nach irgendeinem der Ansprüche 1 bis 4, wobei das Filter ein aus diskreten Komponenten zusammengesetztes Filter ist.
EP93301243A 1992-03-09 1993-02-19 Elektrisches Filter Expired - Lifetime EP0560503B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI921025 1992-03-09
FI921025A FI90478C (fi) 1992-03-09 1992-03-09 Suodatin

Publications (2)

Publication Number Publication Date
EP0560503A1 EP0560503A1 (de) 1993-09-15
EP0560503B1 true EP0560503B1 (de) 1998-11-04

Family

ID=8534886

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93301243A Expired - Lifetime EP0560503B1 (de) 1992-03-09 1993-02-19 Elektrisches Filter

Country Status (7)

Country Link
EP (1) EP0560503B1 (de)
JP (1) JPH06120708A (de)
AU (1) AU661556B2 (de)
CA (1) CA2091089A1 (de)
DE (1) DE69321859T2 (de)
DK (1) DK0560503T3 (de)
FI (1) FI90478C (de)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI110391B (fi) * 1995-11-08 2003-01-15 Solitra Oy Kotelorakenteinen suodatin
FI980911A (fi) * 1998-04-24 1999-10-25 Nokia Networks Oy Resonaattorirakenne
JP2003204203A (ja) * 2002-01-08 2003-07-18 Murata Mfg Co Ltd 方向性結合器付きフィルタおよび通信装置
DE102009050579A1 (de) 2008-10-23 2010-04-29 Bury Gmbh & Co. Kg Mobilgerätsystem für ein Kraftfahrzeug
DE102009050529B4 (de) 2009-10-23 2020-06-04 Volkswagen Ag Mobilgerätsystem für ein Kraftfahrzeug
DE202009017289U1 (de) 2009-12-22 2010-03-25 Volkswagen Ag Bedienteil zur Bedienung eines Mobiltelefons in einem Kraftfahrzeug

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2261325A (en) * 1991-05-03 1993-05-12 Motorola Inc Transmitter filter with integral directional coupler for cellular telephones

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE518176A (de) * 1952-05-08
US3829770A (en) * 1971-10-26 1974-08-13 Coaxial Dynamics Inc Directional coupler for transmission lines
US4232401A (en) * 1979-08-20 1980-11-04 The United States Of America As Represented By The Secretary Of The Army Millimeter wave image guide integrated balanced mixer
US4433314A (en) * 1982-01-21 1984-02-21 The United States Of America As Represented By The Secretary Of The Navy Millimeter wave suspended substrate multiplexer
GB8305411D0 (en) * 1983-02-26 1983-03-30 Lucas Ind Plc Microwave filter
CA1218119A (en) * 1984-03-15 1987-02-17 Andrey Polischuk Overload protector

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2261325A (en) * 1991-05-03 1993-05-12 Motorola Inc Transmitter filter with integral directional coupler for cellular telephones

Also Published As

Publication number Publication date
EP0560503A1 (de) 1993-09-15
FI90478B (fi) 1993-10-29
DE69321859T2 (de) 1999-05-12
FI90478C (fi) 1994-02-10
AU661556B2 (en) 1995-07-27
FI921025A (fi) 1993-09-10
DE69321859D1 (de) 1998-12-10
AU3397393A (en) 1993-09-16
CA2091089A1 (en) 1993-09-10
DK0560503T3 (da) 1999-07-19
JPH06120708A (ja) 1994-04-28
FI921025A0 (fi) 1992-03-09

Similar Documents

Publication Publication Date Title
US5432489A (en) Filter with strip lines
US5023866A (en) Duplexer filter having harmonic rejection to control flyback
EP1419560B1 (de) verbindungseinrichtung mit hoher datenrate
US3641464A (en) Directional communication signal tap
JPH06501833A (ja) 無線装置用方向性結合器
US6201453B1 (en) H-plane hermetic sealed waveguide probe
KR100313717B1 (ko) 대칭적인 감쇄극 특성을 갖는 유전체 공진기형 대역 통과 필터
GB1562842A (en) Electrical branching filter
JP4611811B2 (ja) フィンライン型マイクロ波帯域通過フィルタ
US2951149A (en) Microwave radio receiver
EP0560503B1 (de) Elektrisches Filter
IT9067371A1 (it) Trasduttore ortomodo tra guida d'onda circolare e cavo coassiale
CN214848990U (zh) 一种渐变线定向耦合器
CN110165347A (zh) 一种加载开路枝节的高隔离度微带双工器
CN112424994A (zh) 分支线耦合器
US4427953A (en) Microwave diplexer
AU732191B2 (en) Microwave resonator
WO1988003711A1 (en) Probe coupled waveguide multiplexer
US4147980A (en) Redundant rf system for space application
US5745328A (en) Electromagnetic impulse suppression curcuit
US6809615B2 (en) Band-pass filter and communication apparatus
US5546057A (en) Antenna/filter combiner
JPS60165103A (ja) 誘電体共振器のリアクタンス調整方法
US3504304A (en) Wideband hybrid ring network
US2897499A (en) Uhf antenna multicoupler system or the like

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): CH DE DK FR GB IT LI SE

17P Request for examination filed

Effective date: 19931018

17Q First examination report despatched

Effective date: 19950811

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE DK FR GB IT LI SE

REG Reference to a national code

Ref country code: CH

Ref legal event code: NV

Representative=s name: E. BLUM & CO. PATENTANWAELTE

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 69321859

Country of ref document: DE

Date of ref document: 19981210

ET Fr: translation filed
ITF It: translation for a ep patent filed

Owner name: MODIANO & ASSOCIATI S.R.L.

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

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: CH

Payment date: 20000228

Year of fee payment: 8

REG Reference to a national code

Ref country code: CH

Ref legal event code: PFA

Free format text: LK-PRODUCTS OY TRANSFER- FILTRONIC LK OY

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

Ref country code: FR

Payment date: 20010213

Year of fee payment: 9

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

Ref country code: LI

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

Effective date: 20010228

Ref country code: CH

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

Effective date: 20010228

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

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

Ref country code: FR

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

Effective date: 20021031

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

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

Ref country code: DE

Payment date: 20030227

Year of fee payment: 11

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

Ref country code: DK

Payment date: 20040123

Year of fee payment: 12

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

Ref country code: SE

Payment date: 20040204

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: 20040218

Year of fee payment: 12

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: 20040901

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

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050219

Ref country code: GB

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

Effective date: 20050219

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

Ref country code: SE

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

Effective date: 20050220

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

Ref country code: DK

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

Effective date: 20050228

REG Reference to a national code

Ref country code: DK

Ref legal event code: EBP

EUG Se: european patent has lapsed
GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20050224