WO2017203216A1 - Appareil de filtre multibande et son procédé d'utilisation - Google Patents

Appareil de filtre multibande et son procédé d'utilisation Download PDF

Info

Publication number
WO2017203216A1
WO2017203216A1 PCT/GB2017/051403 GB2017051403W WO2017203216A1 WO 2017203216 A1 WO2017203216 A1 WO 2017203216A1 GB 2017051403 W GB2017051403 W GB 2017051403W WO 2017203216 A1 WO2017203216 A1 WO 2017203216A1
Authority
WO
WIPO (PCT)
Prior art keywords
filter apparatus
resonating means
resonating
band filter
radio frequency
Prior art date
Application number
PCT/GB2017/051403
Other languages
English (en)
Inventor
Evaristo MUSONDA
Richard PARRY
Original Assignee
Radio Design Limited
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 Radio Design Limited filed Critical Radio Design Limited
Priority to GB1819089.2A priority Critical patent/GB2566182A/en
Publication of WO2017203216A1 publication Critical patent/WO2017203216A1/fr

Links

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
    • H01P1/201—Filters for transverse electromagnetic waves
    • H01P1/205—Comb or interdigital filters; Cascaded coaxial cavities
    • 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
    • H01P1/00—Auxiliary devices
    • H01P1/20—Frequency-selective devices, e.g. filters
    • H01P1/207—Hollow waveguide filters
    • H01P1/208—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure
    • 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
    • H01P1/207—Hollow waveguide filters
    • H01P1/208—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure
    • H01P1/2084—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure with dielectric resonators

Definitions

  • This invention relates to a multi-band filter apparatus and to a method of use thereof.
  • Filter apparatus is typically used in telecommunication systems to compensate for disturbances, such as interference, that may affect one or more transmission signals being sent and/ or received by the telecommunication system.
  • the filter apparatus is designed to remove unwanted components from the transmit and/or receive signals and/or enhance the desired transmit and/or receive signals.
  • Many components of a mobile communication cell site, forming part of a telecommunications system contain filters or filter apparatus, such as for example, radios, base transceiver stations (BTSs), combiners, multiplexers and tower mounted amplifiers (TMAs).
  • Each filter or filter apparatus is designed such that it allows one or more radio signals at frequencies within their allocated passband to pass through the same but to reject or substantially reject one or more radio signals at frequencies outside of their allocated passband.
  • the microwave region of the electromagnetic spectrum is an essential yet finite resource used by both civilian and military applications such as radar, navigation and wireless communications.
  • Mobile radio communications require careful allocation of the spectrum by the relevant national or international authorities to service providers, who in turn may divide their slots into narrower sub bands for allocation to individual operators.
  • each filter has one passband associated with the same. This results in multiple components being required for a mobile communication cell site so that multiple radio frequency bands can be supported. For example, traditionally multiple BTSs have been provided in a cell site, with each BTS associated with a particular radio frequency band.
  • An example of a filter response from a conventional filter operating in a single passband is shown in figure 1.
  • the return loss and insertion loss/attenuation (Mag dB) are shown on the vertical axes and the frequency (MHz) of the signals passing through the filter are shown on the horizontal axis.
  • the region 2 where the insertion loss is low shows the frequency of the passband of the filter. In the passband the return loss is shown by the regions 4 and at these frequencies a small proportion of an incident signal is reflected by the filter.
  • the network topology of filter apparatus that produces the filter response of figure 1 is shown in figure 2.
  • the filter apparatus typically comprises a conductive housing with a plurality of resonant cavities defined therein and a resonator 6 located in each cavity.
  • Each resonator 6 is an electronic and/or electromechanical component that exhibits resonance for a narrow range of frequencies.
  • the apparatus will have an input port 5 for allowing one or more radio frequency signals to enter the filter apparatus, and an output port 7 for allowing one or more radio frequency signals at the passband of the filter to leave the apparatus.
  • pre-determined electromagnetic couplings 8 between the resonators 6.
  • the filter or filter apparatus used in such cell site apparatus is often referred to as a dual band or multi-band filter.
  • An example of a filter response from a dual band filter is shown in figure 3.
  • the two large central peaks 10, 12 represent the two different and distinct passbands of the filter.
  • the two sets of smaller peaks 14, 16 offset from the centre show the radio frequency signals reflected by the filter apparatus at each passband.
  • An example of the dual band filter apparatus that produces the filter response of figure 3 is shown in figure 4.
  • the apparatus includes an input port 5 for allowing one or more radio frequency signals to enter the apparatus, and an output port 7 allowing one or more radio frequency signals at the passbands of the apparatus to leave the apparatus.
  • Filter 18 contains a plurality of resonators 6a with electromagnetic couplings between the same.
  • the resonators 6a of filter 18 are tuned so as to have a first passband frequency. As such, only radio frequency signals falling within the first passband frequency will pass through filter path 18.
  • Filter 20 contains a plurality of resonators 6b with electromagnetic couplings between the same.
  • the resonators 6b of filter 20 are tuned so as to have a second passband frequency different to the first passband frequency. As such, only radio frequency signals falling within the second passband frequency will pass through the filter path 20.
  • Radio signals falling outside of the first and second pass band frequencies will be substantially reflected by the filter apparatus.
  • this type of filter apparatus allows multiple frequency bands to be filtered, there are a number of problems associated with the same.
  • the diplexing junctions at each end of the filter apparatus are often difficult to physically realise and they take up valuable space, which is particularly problematic when the equipment in which it is used is being located at the top of a cell site mast where space is limited.
  • the resulting network does not allow the filter designer to have full control over the location of transmission zeroes in the filter response.
  • the transmission zeroes are the frequencies at which the filter completely attenuates incident signals and are required in order to produce filters with rapid roll offs.
  • multi-band filter apparatus said filter apparatus including a housing in which at least one resonating means is provided, said at least one resonating means capable of resonating at one or more frequencies, and wherein each of said at least one resonating means is arranged such that one or more radio frequency signals in at least two different and distinct passbands are able to pass therethrough in use.
  • the resonating means within the filter apparatus By arranging the resonating means within the filter apparatus to allow radio frequency signals of at least two or more different and distinct passbands to pass therethrough, this means that only a single or a reduced number of filter paths need to be provided in the multi-band filter apparatus.
  • This has the advantage that it removes the requirement of complex diplex junctions being needed and therefore the filter apparatus can be realised more easily, and smaller, more compact filter designs, can be produced.
  • the filter design allows the introduction of more cross couplings, this allows the location of transmission zeroes to be controlled.
  • the apparatus includes at least two and/or a plurality of resonating means.
  • Each of said two and/or plurality of resonating means is arranged such that the radio frequency signals in the at least two different and distinct passbands are able to pass therethrough.
  • the housing defines at least one resonator cavity.
  • the at least one resonating means is provided in or associated with the at least one resonator cavity.
  • a single resonating means is provided in a single resonator cavity.
  • two or more resonating means can be provided in a single resonator cavity.
  • two or more resonator cavities are joined, are continuous with and/ or are in communication or fluid communication with each other.
  • all the resonator cavities of the filter apparatus are joined, are continuous with and/ or are in communication or fluid communication with each other.
  • the one or more resonator cavities are formed from and/ or include at least one outer most layer of electrically conductive material.
  • the resonating means is typically defined as an object that is capable of exhibiting resonance or resonant behaviour at one or more frequencies within at least the electromagnetic spectrum.
  • the resonating means can include or consist of a single physical resonator and/or a single resonator mode or section.
  • Each resonator and/or resonating mode or section is arranged to allow one or more radio frequency signals of two or more different and distinct passbands to pass therethrough.
  • a single resonator may include, comprise or consist of two or more resonant modes or sections within the limits of the two or more different and distinct pass bands.
  • a radio frequency signal falling within any of the pass bands will pass through each resonant mode or section.
  • each resonating means is arranged to allow one or more radio frequency signals of two or more different and distinct passbands to pass through the same resonant mode of each resonating means.
  • the resonating means can include any or any combination of a combline resonator, a ceramic resonator, a dielectric resonator, ceramic puck, ceramic rod and/ or the like.
  • two or more resonating means are coupled together via electromagnetic coupling.
  • two or more resonating means are arranged so as to have electromagnetic cross coupling therebetween.
  • the introduction of the cross coupling allows the location of the transmission zeroes of the filter response to be controlled.
  • one or more transmission zeroes can be located between at least two of the pass bands.
  • the filter apparatus includes at least one input port for receiving one or more radio frequency signals and at least one output port for outputting one or more radio frequency signals.
  • the input port and/ or the output port is each coupled to a single resonating means only.
  • the input port and/or the output port is each coupled to two or more resonating means, and at least one of the two or more resonating means is arranged so as to allow one or more radio frequency signals of two or more distinct and different pass bands to pass therethrough.
  • the filter apparatus has at least two different filter paths.
  • the filter apparatus can be in the form of a diplexer.
  • Each filter path includes at least one resonating means.
  • the different filter paths have a common port joining the filter paths at one end, and separate independent ports for each filter path at the other ends.
  • At least one of the at least two filter paths has two or more passbands.
  • the resonators or resonating means within the filter apparatus are provided in a linear or substantially linear manner with the resonators or resonating means within each linear filter path arranged so as to allow one or more radio frequency signals of two or more different and distinct pass bands to pass therethrough.
  • each resonating means is tuned to, or substantially tuned to within the limits of the at least two or more pass bands (such as for example +/-10% of passband frequency).
  • two or more resonating means can be tuned to different frequencies providing the response of the two or more resonating means together allows one or more radio frequency signals of two different and distinct pass bands to pass through the same.
  • a radio frequency signal from each passband is able to pass through each resonating means of the filter apparatus.
  • the housing of the filter apparatus is an electrically conductive housing, such as for example, a metallic housing, and/or a housing with at least one electrically conductive outer layer or coating provided thereon.
  • the filter housing comprises a base, side walls and a top.
  • the one or more resonant cavities are defined in the housing between the base, side walls and top and have at least one opening in the top of the housing.
  • a lid or closure means can be provided on or associated with the top in use.
  • toning means are provided on or associated with the filter apparatus and/or the one or more resonating means to allow the resonating means to be tuned to the required electromagnetic frequency or frequency range that allows one or more radio frequency signals of at least two different and distinct pass bands to pass therethrough.
  • the passband of the filter apparatus is typically a frequency or frequency range of radio signals that can pass through the filter apparatus. Radio frequency signals falling outside or significantly outside of this frequency or frequency range are reflected by the filter apparatus and are prevented or substantially prevented from passing through the filter apparatus.
  • the frequency response or transfer function of the filter apparatus is calculated and the one or more resonating means and associated circuitry are then designed and arranged to allow the required frequency response and/ or transfer function to be achieved.
  • the transfer function H(j ⁇ ) of a two port network is a function of angular frequency, ⁇ , and states what proportion of the energy entering the network at the input port leaves via the output port.
  • a transfer function can be written in terms of a characteristic function T N :
  • ⁇ Z is the dependent transmission zero that cannot be prescribed
  • N OT7 is the number of transmission zeros at DC and where ls infinite
  • N FTZ are the transmission zeros that can be prescribed and where is infinite
  • T is the number of frequencies ⁇ r where there are turning points in the stopband due to the prescribed transmission zeros (T ⁇ N FTZ )
  • N is the degree of the function and so the number of transmission zeros at infinity is therefore given by N— N 0TZ — N FTZ — 1
  • the equation can be solved using numerical methods. Circuit optimisation techniques can be employed to arrive at the desired response for the filter apparatus.
  • a method of using filter apparatus said filter apparatus including a housing in which at least one resonating means is provided, said at least one resonating means capable of resonating at one or more frequencies, and wherein said method includes the step of tuning each of said at least one resonating means such that one or more radio frequency signals in at least two different and distinct passbands are able to pass through each of said resonating means in use.
  • a telecommunication system including multi-band filter apparatus.
  • Figure 1 is a filter response of a conventional single band filter, with the return loss and insertion loss/attenuation shown on the Y-axis (Mag dB) and the radio frequency shown on the X-axis (MHz);
  • Figure 2 (PRIOR ART) is an example of the resonator arrangement in a conventional single band filter apparatus of a type producing the filter response shown in Figure 1 ;
  • Figure 3 is a filter response of a conventional dual band filter, with the return loss and insertion loss /attenuation shown on the Y-axis (Mag dB) and the radio frequency shown on the X-axis (MHz);
  • Figure 4 is an example of the resonator arrangement in a conventional dual band filter apparatus of a type producing the filter response shown in Figure 3;
  • Figure 5 is an example of a resonator arrangement in multi-band filter apparatus according to an embodiment of the present invention.
  • Figure 6 is a further example of a resonator arrangement in multi-band filter apparatus according to a further embodiment of the present invention.
  • Figure 7a is an example of diplexer filter apparatus according to the prior art.
  • Figure 7b is an example of diplexer filter apparatus according to the present invention
  • Figure 8 is an example of a filter response of the diplexer filter shown in Figure 7b, with the return loss and insertion loss/attenuation shown on the Y-axis (Mag dB) and the radio frequency shown on the X-axis (MHz).
  • multi- band filter apparatus including a housing in which a plurality of resonant cavities are defined (not shown).
  • Resonating means in the form of a resonator is provided in each cavity.
  • a plurality of resonators 22 are electromagnetically coupled together via electromagnetic couplings 24 in series, as shown in the resonator arrangement in figure 5.
  • An input port 26 is provided at the start of the line of resonators and is coupled to the first resonator 22' in the line.
  • An output port 28 is provided at the end of the line of resonators and is coupled to the last resonator 22" in the line.
  • One or more radio frequency signals enter the filter apparatus via input port 26 pass along all the resonators 22 and are output from the filter apparatus via output port 28.
  • each resonator 22, 22'; 22" is arranged such that it allows radio frequency signals of two different and distinct passbands to pass through each of them.
  • each resonator is tuned to a frequency or frequency range which allows signals from both passbands to pass through the same.
  • the filter response of the filter apparatus of the present invention looks similar to the filter response shown in figure 3 but the filter apparatus is arranged in a different manner to that of Figure 4.
  • FIG 6 there is illustrated a further example of an arrangement of resonators in filter apparatus according to an embodiment of the present invention.
  • some of the electromagnetic couplings between the resonators 22 are cross couplings.
  • Electromagnetic couplings 24 are shown by solid lines and electromagnetic cross couplings 30 are shown by dotted lines.
  • each filter path 30, 32 contains a plurality of resonators 34, 36 respectively.
  • the filter paths 30, 32 each have a common port 38 and an independent port 40, 42 respectively.
  • the resonators 34 within filter path 30 allow one or more radio frequency signals of two or more different and distinct passbands (i.e. first and second pass bands) to pass therethrough.
  • the resonators 36 within filter path 32 allow one or more radio frequency signals of two or more different and distinct passbands (i.e. third and fourth pass bands) to pass therethrough.
  • the first and second pass bands are different to the third and fourth pass bands. For example, transmit signals for two different passbands can pass through filter path 30 and receive signals for two different pass bands can pass through filter path 32 in use.
  • the arrangement is different to a conventional diplexer arrangement, an example of which is shown in figure 7a.
  • one common port 44 is coupled to four different resonator paths 46, 48, 50, 52, each resonator path allowing radio frequency signals of a single pass band to pass therethrough.
  • resonator path 46 could be for transmission signals at a first radio frequency
  • resonator path 48 could be for transmission signals at a second radio frequency
  • Resonator path 50 could be for receive signals at the first radio frequency
  • resonator path 52 could be receive signals at the second radio frequency.
  • a first port 54 is coupled to two of the different resonator paths 46, 48, and a second port 56 is coupled to the other two different resonator paths 50, 52.
  • Figure 8 is an example of a filter response from the filter arrangement shown in figure 7b.
  • the frequency peaks 58 and 60 represent the two receive passbands of filter path 32 and the frequency peaks 62 and 64 represent the two transmit passbands of filter path 30.
  • the transfer function ⁇ (j ⁇ ) of a two port network is a function of angular frequency, ⁇ , and states what proportion of the energy entering the network at the input port leaves via the output port.
  • a transfer function can be written in terms of a characteristic function T N :
  • ⁇ Z is the dependent transmission zero that cannot be prescribed
  • N 0T7 is the number of transmission zeros at DC and where ls infinite
  • N FTZ are the transmission zeros that can be prescribed and where
  • T is the number of frequencies ⁇ r where there are taming points in the stopband due to the prescribed transmission zeros (T ⁇ N FTZ )
  • N is the degree of the function and so the number of transmission zeros at infinity is therefore given by N— N 0TZ — N FTZ — 1
  • the equation can be solved using numerical methods, and circuit optimisation techniques can be employed to arrive at the desired response for the filter apparatus.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Filters And Equalizers (AREA)

Abstract

L'invention porte sur un appareil de filtre multibande comprenant un boîtier dans lequel est disposé au moins un moyen de résonance. Le ou les moyens de résonance sont capables de résonner à une ou plusieurs fréquences. Chacun desdits moyens de résonance est agencé de telle sorte qu'un ou plusieurs signaux de radiofréquence dans au moins deux bandes passantes différentes et distinctes puissent passer à travers ceux-ci lors de l'utilisation.
PCT/GB2017/051403 2016-05-23 2017-05-19 Appareil de filtre multibande et son procédé d'utilisation WO2017203216A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1819089.2A GB2566182A (en) 2016-05-23 2017-05-19 Multi-band filter apparatus and method of use thereof

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1608991.4 2016-05-23
GBGB1608991.4A GB201608991D0 (en) 2016-05-23 2016-05-23 Mult-band filter apparatus and method of use thereof

Publications (1)

Publication Number Publication Date
WO2017203216A1 true WO2017203216A1 (fr) 2017-11-30

Family

ID=56369770

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2017/051403 WO2017203216A1 (fr) 2016-05-23 2017-05-19 Appareil de filtre multibande et son procédé d'utilisation

Country Status (2)

Country Link
GB (2) GB201608991D0 (fr)
WO (1) WO2017203216A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113675561A (zh) * 2020-05-14 2021-11-19 大富科技(安徽)股份有限公司 一种滤波器及通信设备

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5349316A (en) * 1993-04-08 1994-09-20 Itt Corporation Dual bandpass microwave filter
US5410284A (en) * 1992-12-09 1995-04-25 Allen Telecom Group, Inc. Folded multiple bandpass filter with various couplings
GB2481291A (en) * 2010-06-14 2011-12-21 Radio Design Ltd A combiner filter to allow multiple BTSs operating in a common frequency band to share a common antenna

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5410284A (en) * 1992-12-09 1995-04-25 Allen Telecom Group, Inc. Folded multiple bandpass filter with various couplings
US5349316A (en) * 1993-04-08 1994-09-20 Itt Corporation Dual bandpass microwave filter
GB2481291A (en) * 2010-06-14 2011-12-21 Radio Design Ltd A combiner filter to allow multiple BTSs operating in a common frequency band to share a common antenna

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
CHEN FU-CHANG ET AL: "Dual-Band Coaxial Cavity Bandpass Filter With Helical Feeding Structure and Mixed Coupling", IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS, IEEE SERVICE CENTER, NEW YORK, NY, US, vol. 25, no. 1, 1 January 2015 (2015-01-01), pages 31 - 33, XP011569322, ISSN: 1531-1309, [retrieved on 20150106], DOI: 10.1109/LMWC.2014.2369965 *
HONG-MING LEE ET AL: "Dual-band coupling and feed structure for microstrip filter design", MICROWAVE SYMPOSIUM DIGEST, 2004 IEEE MTT-S INTERNATIONAL FORT WORTH, TX, USA JUNE 6-11, 2004, PISCATAWAY, NJ, USA,IEEE, vol. 3, 6 June 2004 (2004-06-06), pages 1971 - 1974, XP010728138, ISBN: 978-0-7803-8331-9, DOI: 10.1109/MWSYM.2004.1338997 *
KENNETH S K YEO ET AL: "8 pole high temperature superconductor microstrip dual band bandpass filter design", MICROWAVE SYMPOSIUM DIGEST (MTT), 2011 IEEE MTT-S INTERNATIONAL, IEEE, 5 June 2011 (2011-06-05), pages 1 - 4, XP032006592, ISBN: 978-1-61284-754-2, DOI: 10.1109/MWSYM.2011.5972643 *
LAIYUN JI ET AL: "Design and performance of dual-band high temperature superconducting filter", SCIENCE CHINA INFORMATION SCIENCES, SP SCIENCE CHINA PRESS, HEIDELBERG, vol. 55, no. 4, 30 May 2011 (2011-05-30), pages 956 - 961, XP035028707, ISSN: 1869-1919, DOI: 10.1007/S11432-010-4173-8 *
SARAWUTH CHAIMOOL ET AL: "Resonator-Embedded Four-Pole Cross-Coupled Dual-Band Microstrip Bandpass Filters", COMMUNICATIONS AND INFORMATION TECHNOLOGIES, 2006. ISCIT;06. INT ERNATIONAL SYMPOSIUM ON, IEEE, PI, 1 October 2006 (2006-10-01), pages 1076 - 1079, XP031068326, ISBN: 978-0-7803-9740-8 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113675561A (zh) * 2020-05-14 2021-11-19 大富科技(安徽)股份有限公司 一种滤波器及通信设备

Also Published As

Publication number Publication date
GB2566182A (en) 2019-03-06
GB201819089D0 (en) 2019-01-09
GB201608991D0 (en) 2016-07-06

Similar Documents

Publication Publication Date Title
CN105938928B (zh) 涉及多极陶瓷谐振器滤波器的装置和方法
EP2227859B1 (fr) Procédés de conception de filtres et filtres basés sur des structures métamatérielles
KR101919456B1 (ko) 일체형 유전체 세라믹 도파관 듀플렉서
US20100188167A1 (en) Ku-band diplexer
US9899716B1 (en) Waveguide E-plane filter
CN110808440A (zh) 一种介质波导双工器
CN104425858B (zh) 滤波器
CN106129558A (zh) 基于开口谐振环结构的超材料微波滤波器
EP3416232A1 (fr) Dispositif électronique à module de filtre par fréquence radio (rf) avec résonateurs coaxiaux empilés et procédés associés
EP3386028B1 (fr) Combineur
KR101391399B1 (ko) Ｃｒｌｈ 구조의 대역저지 여파기 및 그 제조 방법
WO2017203216A1 (fr) Appareil de filtre multibande et son procédé d'utilisation
KR101126676B1 (ko) 다중대역 안테나 스위칭 모듈용 필터
US7573355B2 (en) Integrated bandpass/bandstop coupled line filter
US10454148B2 (en) Compact band pass filter
KR20030084603A (ko) 하이브리드 기술을 사용하는 초-선택성 광대역 대역 통과필터
EP3301753A1 (fr) Appareil multiplexeur et son procédé d'utilisation
JP4842245B2 (ja) トリプレクサ回路
EP4060805A1 (fr) Filtres comprenant des lignes de transmission de filtre passe-bande
KR102280090B1 (ko) 듀플렉서 유전체 필터
US6703911B1 (en) Very high frequency (VHF) sharp tuned elliptic filter and method
Lakshmidevi et al. Design of diplexer for LTE-28/26 band using D-CRLH transmission line metamaterials
CN116470252A (zh) 带通滤波器
CN113054374A (zh) 通信设备及滤波器
CN113054382A (zh) 通信设备及其滤波器

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 201819089

Country of ref document: GB

Kind code of ref document: A

Free format text: PCT FILING DATE = 20170519

NENP Non-entry into the national phase

Ref country code: DE

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17726670

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 17726670

Country of ref document: EP

Kind code of ref document: A1