US3452300A - Four port directive coupler having electrical symmetry with respect to both axes - Google Patents

Four port directive coupler having electrical symmetry with respect to both axes Download PDF

Info

Publication number
US3452300A
US3452300A US478930A US3452300DA US3452300A US 3452300 A US3452300 A US 3452300A US 478930 A US478930 A US 478930A US 3452300D A US3452300D A US 3452300DA US 3452300 A US3452300 A US 3452300A
Authority
US
United States
Prior art keywords
network
coupler
port
coupling
mode
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
US478930A
Other languages
English (en)
Inventor
Joseph D Cappucci
Harold Seidel
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.)
Merrimac Research & Dev Inc
Original Assignee
Merrimac Research & Dev Inc
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 Merrimac Research & Dev Inc filed Critical Merrimac Research & Dev Inc
Application granted granted Critical
Publication of US3452300A publication Critical patent/US3452300A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/01—Frequency selective two-port networks
    • H03H7/17—Structural details of sub-circuits of frequency selective networks
    • H03H7/1708—Comprising bridging elements, i.e. elements in a series path without own reference to ground and spanning branching nodes of another series path
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/01—Frequency selective two-port networks
    • H03H7/0115—Frequency selective two-port networks comprising only inductors and capacitors
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/18—Networks for phase shifting
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/18—Networks for phase shifting
    • H03H7/21—Networks for phase shifting providing two or more phase shifted output signals, e.g. n-phase output
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/48—Networks for connecting several sources or loads, working on the same frequency or frequency band, to a common load or source

Definitions

  • FIG. 9A is a diagrammatic representation of FIG. 9A
  • This invention relates to devices for coupling radio frequency energy and more particularly to couplers constructed in accordance with imposed conditions of duality.
  • An object is to provide coupling devices formed by symmetrical networks using imposed conditions of duality.
  • An additional object is to provide coupling devices formed by symmetrical networks and having desired coupling properties which are constructed using imposed conditions of duality in which the normalized input impedance of the even mode equivalent circuit bisection is equal to the normalized admittance of the odd mode equivalent circuit bisection.
  • 'Another object is to provide devices for coupling radio frequency energy using lumped circuit components in which the values of the components at a particular frequency of operation are selected in accordance with imposed condition of duality.
  • Yet a further object is to provide radio frequency energy coupling devices having a plurality of obstacles using lumped constant components for both the elements of the coupler obstacles and for connecting the plurality of obstacles together.
  • An additional object is to provide radio frequency coupling devices having a plurality of obstacles and using lumped constant components for both the elements of the coupler obstacles and for connecting the obstacles together, such elements being selected in accordance with imposed conditions of duality, and means for correcting for dispersion of the devices.
  • radio frequency energy coupling networks are provided which are relatively simple to construct and have desired isolation, input match, coupled output, energy transmission and frequency responsive characteristics.
  • These couplers are constructed as symmetric networks from lumped constant components whose values are selected in accordance with conditions of duality imposed upon the network.
  • the duality condition is that the input impedance of the even mode bisection of the network equals the input admittance of the odd mode bisection.
  • FIG. 1 shows a four terminal symmetric coupler network
  • FIGS. 2A and 2B show the even and odd mode bisections of the network of FIG. 1
  • FIG. 3 is a schematic diagram of a four terminal symmetric coupler network formed of lumped constant components
  • FIG. 4 is a schematic diagram of the bisection of the network of FIG. 3
  • FIGS. 5A and 5B respectively are the odd mode and even mode equivalent circuits for the bisection of FIG. 4
  • FIG. 6 is a schematic diagram of a two obstacle coupler network
  • FIG. 7 is a schematic diagram of a two obstacle coupler using lumped constant components
  • FIGS. 1 shows a four terminal symmetric coupler network
  • FIGS. 2A and 2B show the even and odd mode bisections of the network of FIG. 1
  • FIG. 3 is a schematic diagram of a four terminal symmetric coupler network formed of lumped constant components
  • FIG. 4 is a schematic diagram of the bisection of the network of FIG. 3
  • FIGS. 8A and 8B respectively show the even and odd mode bisections of the coupler of FIG. 7;
  • FIGS. 9A and 98 respectively show the equivalent transmission line type circuits for the bisections of FIGS. 8A and 8B;
  • FIG. 10 is a schematic diagram of a coupler of the type shown in FIG. 7 with additional elements provided for correcting dispersion.
  • FIGURE 1 shows in general block notation a symmetric four terminal network 10 of the type to be considered having components (not shown) which are frequency responsive to change their impedances and admittances.
  • the network has four ports 1, 2, 3 and 4, and is of the type such that when an input signal is applied to port 1, a coupled output signal is produced at port 2, a transmitted output signal produced at port 3 in phase quadrature with the coupled output at port 2, and port 4 is isolated so that no output signal appears thereon.
  • Many such networks are well known in the art.
  • network 10 is symmetrical, in accordance with theory of analysis it is said to have a plane of symmetry 12 so that a voltage V applied between input ports 1 and 2, with the other ports 3 and 4 terminated with the proper impedances, can be broken up into the two equivalent modes of excitation applied between ports 1 and 2. These two modes are, as shown in FIG. 1, an even mode excitation of /2V and /2V applied to the respective ports 1 and 2 and an odd mode excitation of /zV and /2V applied to the same two ports.
  • the even and odd mode analysis is shown for example in an article by S. B. Cohn entitled Shielded Coupled-Strip Transmission Line in the October 1955 Transactions IRE, Volume PGMTI.
  • Letting Z be the normalized input impedance for the even mode bisection of FIG. 2A, where the normalized input impedance equals the input impedance of the network at any one frequency divided by the characteristic input impedance of the network, it can be shown by network analysis that:
  • Equations 1 through 4 and 5a through 8a are added, giving:
  • Equations 10 through 13 define the symmetric network 10 of FIG. 1 as a directional coupler having the following characteristics:
  • the coupled output at port 2 can be shown to be in phase quadrature with the transmitted output at port 3.
  • Couplers of the present invention are produced using imposed duality conditions with lumped circuit elements, such as .4 capacitors and inductances.
  • lumped circuit elements such as .4 capacitors and inductances.
  • Coupler 20 is a symmetrical network for-med by a lumped inductor 21 whose two coils respectively have their ends connected to ports 1 and 3 and ports 2 and 4. Ports 1 and 2 are shunted by a lumped capacitor 23 of capacitance C.
  • the wires of the two coils forming inductance 21 are preferably twisted together and both wires are wound on a coil form or a toroidal core to form a bifilar winding.
  • any bifilar inductor such as inductor 21, the odd, or anti-symmetric, mode inductance is less than the even, or symmetric, mode inductance. This is so because in the odd mode most of the electromagnetic field is contained between the wires while the even, or symmetric mode inductance remains large.
  • a bifilar inductor can be wound to have a considerable difference between the even mode and odd mode inductances.
  • the odd mode inductance L of a bifilar inductor is measured as a series connection of the pair of wires, each having an inductance L forming the inductor. Since the wires each of inductance L are connected in series, the total odd mode inductance L equals /2L,,,.
  • the capacitance of capacitor 23a is 2C since half of the total capacitance C of capacitor 23 was taken and capacitors in series are added by adding their reciprocals.
  • Resistor 25 designates the terminating impedance of the network, and is shown as having a value of one (1) unit.
  • the value L is shown for the inductance of the one wire of bifilar inductor 21 assumed to be in the half of the network encompassed by the bisecting plane 12.
  • FIG. 5A The odd mode equivalent circuit for the bisected network of FIG. 4 is shown in FIG. 5A.
  • bisecting plane 12 is considered to be a short circuit plane in the odd mode meaning that the capacitor 23a of value 20 is in parallel with the output impedance 25.
  • the inductance of the inductor 21 is neglected since it is very small in the odd mode, as explained above.
  • FIG. SB shows the even mode equivalent circuit for the bisected circuit of FIG. 4. Since bisecting plane 12 is an open circuit plane for the even mode, the capacitor 23a has no effect and the inductance of the coil 21 is the high value even mode inductance L
  • the normalized input admittance is:
  • Equation 5 the reflection coefficient I of the circuit of FIG. 5A is:
  • Equations 1 through 8 and 5a through 8a Using Equations 1 through 8 and 5a through 8a to obtain the even and odd mode scattering coefiicients for the network of FIGS. 3-5 in terms of the even mode coefiicient and adding the even and odd coefficients in accordance with Equations 10 through 13 to obtain the scattering coeflicients for the entire symmetrical four-port network gives:
  • the coupling k in db between ports 1 and 2 of the coupler of FIG. 3 is given as:
  • Equation 26 is used to solve for x which, from Equation 21a, is equal to b. For any predetermined frequency of operation and input impedance level the value of the inductance 21 and capacitor 25 can be determined.
  • FIG. 6 a two obstacle coupler is used.
  • This coupler 30 is shown in FIG. 6.
  • Network 20-1 has a capacitor 23-1 (C shunted across the ports 1 and 2 and a bifilar inductor 21-1 connected in the same manner as network 20 of FIG. 3.
  • Network 20-2 is the same as 20-1 and has a bifilar inductor 21-2 and a capacitor 23-2, the latter of which is connected in shunt across output ports 3 and 4 and to the ends of the two wires of inductor 21-2.
  • the ideal elements 32 for coupling networks 20-1 and 20-2 together are, of course, transmission lines of the proper length and characteristics for matching the characteristic impedances of the two networks, so that the imposed duality condition -is not destroyed.
  • a pair of such lines would be used, one connecting each of the corresponding coils of the two bifilar inductors 21-1 and 21-2.
  • the impedances of element 32 are non-dispersive, that is, have substantially linear phase shift and have no attenuation over the operating frequency range, then designing the two obstacle coupler 30 is a straight forward aplication of the design principles for the single obstacle coupler described above.
  • the lengths of the two transmission line coupling elements 32 between networks 20-1 and 20-2 needed to preserve the duality condition would be fairly long and would make the coupler considerably bulky.
  • lumped constant components are preferably used for the coupling elements 32.
  • the transmission lines have dispersive properties. Therefore, the coupler must also have the same dispersive properties at a particular frequency of operation as the equivalent lengths of transmission lines, in order to maintain the imposed duality conditions to achieve the desired characteristic for the coupler.
  • Such a network is illustrated in FIG. 7.
  • FIG. 7 illustrates a symmetrical two obstacle coupler 40 with a coupling network formed by lumped constant components in the form of inductors and capacitors.
  • the same reference numerals used previously are used here again for the same components.
  • the lumped constant component equivalent for each connecting transmission line of FIG. 6 is shown as a T-circuit having two inductors 41 and 42 and a shunt capacitor 43.
  • the upper T-circuit has series connected inductors 41-1, 42-1 and a shunt capacitor 43-1, whose lower end is connected to a point of reference potential such as ground 44, connecting the ends of the upper wires of bifilar inductors 21-1 and 21-2.
  • Inductances 41-1 and 42-1 are single coil inductors.
  • FIGS. 8A and 8B respectively show the even and odd mode bisections of the coupler 40 of FIG. 7. As in FIGS. 3 and 4, the even mode inductance L of each bifilar inductor 21-1 and 21-2 is 2 L The odd mode inductance L,, for each of 21-1 and 21-2 is L /2L,,.
  • the inductances of coupling coils 41 and 42 in each mode is L while the capacitance of capacitor 43 is 2C. Since the even mode bisection plane 12 is an open circuit plane, capacitors 23-1 and 23-2 do not appear in the even mode bisection of FIG. 8A. In the odd mode bisection of FIG. 8B, where plane 12 is a short circuit plane, capacitors 23-1 and 23-2 have a value of 2C. It should again be pointed out that the even and odd mode bisections are circuits with identical properties, although the circuits are shown in somewhat different form, since network 40 is symmetrical.
  • FIGS. 9A and 9B respectively show the even and odd mode equivalent circuits of FIGS. 8A and 8B.
  • the even mode equivalent circuit has been redefined as an equivalent transmission line T-circuit with a pair of series connected inductors 44-1 and 45-1 of values L and L respectively, shunt capacitor 43-1 of value 2C connected to ground, and a second pair of series connected inductors 45-2 and 44-2 of values L and L connected to the junction of inductor 41-1 and capacitor 43-1.
  • the two inductors 45-1 and 45-2 of value L give the even mode inductance of the equivalent of T-section transmission line.
  • the value L also includes the inductance of the bifilar transformers 21, which is not negligible in the case where two networks are connected together.
  • the two inductors 44-1 and 44-2 of value of L are the coupling obstacles (inductances) of the equivalent transmission line. From FIGS 8A and 9A it is clear that:
  • FIG. 9B The odd mode bisection of FIG. 8B is also shown in FIG. 9B for purposes of analysis as an equivalent transmission line T section.
  • This section is formed by series connected coils 41-1 and 46-2 of value L connected at their junction by capacitor 43-1 of value 2C to ground.
  • the unconnected ends of coils 46 are shunted to ground by the capcitors 23-1 and 23-2 of value 2C
  • capacitors 23-1 and 23-2 are the coupling obstacles of the equivalent line T sections and:
  • FIGS. 8A and 8B are uncoupled to each other, due to the symmetry of original network 40 and the nature of the bisecting planes 12.
  • These bisected circuits of FIGS. 8A and 8B are also identical, so that the even and odd mode T-section transmission line equivalents of FIGS. 9A and 9B are also identical so that:
  • the equivalent transmission line coupling elements between the two networks 20-1 and 20-2 are to have dispersive properties.
  • Equation 41a, 41b and 410 L corresponds to an inductance 45-1 or 45-2 of FIG. 9A, C corresponds to one-half the value of capacitor 43-1, and w is the cutoif frequency of the T-section network.
  • Equation 41b and 41c in (37) gives:
  • L can be calculated such that Any set of values of L and L can be used to fabricate L so long as L,,/2 is equal to or less than L,,.
  • the network 40 of FIG. 7 is dispersive, that is, its characteristic impedance is not constant and its phase shift is not linear with frequency, but the eifects of dispersion (Z Z cos 0) can be readily accounted for. Since 0 is known for any given coupling and Z is known, Z for the elements 32 coupling the two networks 20-1 and 20-2 together is also known. The same dispersion value Z can be realized by connecting equivalent dispersive elements to the network 40. Since the entire network 40 is a four terminal device with T-sections having constant k and frequency responsive properties, that is, it has a passband, it is effectively a constant K prototype filter. Therefore, other filters can be placed at each terminal 1-4 of network 40 to reduce the dispersion and make the network more linear. A preferred filter is the so-called m-derived end section (or half section) which can be connected to network 40 to correct the dispersion of the system.
  • FIG. 10 shows the network 40 of FIG. 6 with an mderived end section 60 connected to each port.
  • Each end section '60 is shown in the conventional manner by the three generalized impedances 60a, 60b and 600 of the mderived 1r configuration half section.
  • the dispersion of the network 40 can be significantly reduced over a selected frequency range of operation.
  • Design of m-derived filters is highly conventional in the art, so the details thereof are not given here.
  • a four port directive coupler for controlled response over a broad band of frequencies said coupler possessing electrical symmetry with respect to both axes and comprising:
  • first network means formed substantially of lumped constant frequency responsive components, means connecting said components so that said first network means has a pair of input ports and a pair of output ports, one of said pair of input ports serving as the input port of the coupler and the other serving as the coupler coupled output port,
  • second network means formed substantially of lumped constant frequency responsive components having a pair of input ports and a pair of output ports, one of said output ports serving as the output port of the coupler and the other serving as the isolated port of the coupler,
  • said lumped constant components of said first and second network means formed by a pair of highly magnetically coupled conductors and a capacitor in shunt with two of the ends of the conductors,
  • a symmetrical four port coupling network as in claim 1 further comprising means connected to at least one of said first and second network means for reducing the dispersion of the symmetrical coupler.
  • each of said transmission line means is substantially nondispersive over a substantial portion of the operating band of the directive coupler.
  • each of said first and second network means comprises a bifilar wound inductor having one end of each winding electrically connected to a respective port of one of the pairs of input and output ports, a lumped capacitor means shunted across said one end of each of the two windings, and means connecting the other end of each winding of the bifilar inductor to a respective port of the other one of the pairs of input and output ports.
  • a symmetrical four port network as set forth in claim 6 wherein the electrical coupling means connecting the output ports of the first network means and the input ports of the second network means comprises a lumped constant transmission means formed of a cascade of series inductors and shunt capacitors connected between an output port of the first network means and an input port of the second network means.
  • a symmetrical four port network as set forth in claim 8 further comprising means connected to a port of one of said network means for reducing the dispersion of the symmetrical coupler.
  • a coupling network as set forth in claim 11 wherein said means for reducing dispersion comprises an m-derived filter end section.
  • Equation (6a) should appear as shown below:

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Filters And Equalizers (AREA)
  • Near-Field Transmission Systems (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Variable-Direction Aerials And Aerial Arrays (AREA)
US478930A 1965-08-11 1965-08-11 Four port directive coupler having electrical symmetry with respect to both axes Expired - Lifetime US3452300A (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
US47893065A 1965-08-11 1965-08-11
US52742166A 1966-02-15 1966-02-15
US74205268A 1968-07-02 1968-07-02
GB6036269 1969-12-10
DE19702000065 DE2000065B2 (de) 1965-08-11 1970-01-02 Frequenzabhaengige schaltungsanordnung

Publications (1)

Publication Number Publication Date
US3452300A true US3452300A (en) 1969-06-24

Family

ID=27510085

Family Applications (3)

Application Number Title Priority Date Filing Date
US478930A Expired - Lifetime US3452300A (en) 1965-08-11 1965-08-11 Four port directive coupler having electrical symmetry with respect to both axes
US527421A Expired - Lifetime US3452301A (en) 1965-08-11 1966-02-15 Lumped parameter directional coupler
US742052A Expired - Lifetime US3514722A (en) 1965-08-11 1968-07-02 Networks using cascaded quadrature couplers,each coupler having a different center operating frequency

Family Applications After (2)

Application Number Title Priority Date Filing Date
US527421A Expired - Lifetime US3452301A (en) 1965-08-11 1966-02-15 Lumped parameter directional coupler
US742052A Expired - Lifetime US3514722A (en) 1965-08-11 1968-07-02 Networks using cascaded quadrature couplers,each coupler having a different center operating frequency

Country Status (4)

Country Link
US (3) US3452300A (enrdf_load_stackoverflow)
JP (1) JPS4841057B1 (enrdf_load_stackoverflow)
DE (2) DE1541483B2 (enrdf_load_stackoverflow)
GB (2) GB1159367A (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3506932A (en) * 1968-02-28 1970-04-14 Bell Telephone Labor Inc Quadrature hybrid coupler
US3576505A (en) * 1969-10-27 1971-04-27 Bell Telephone Labor Inc Transformer hybrid coupler having arbitrary power division ratio
US3605044A (en) * 1968-11-18 1971-09-14 Bell Telephone Labor Inc Filter structures using bimodal, bisymmetric networks
US3723913A (en) * 1972-05-30 1973-03-27 Bell Telephone Labor Inc Quadrature hybrid coupler using one-port, linear circuit elements
US3723914A (en) * 1972-01-26 1973-03-27 J Cappucci Lumped constant quadrature coupler with improved parasitic suppression
US3869585A (en) * 1972-12-19 1975-03-04 Lorch Electronics Corp Asymmetric quadrature hybrid couplers
US3883827A (en) * 1974-05-02 1975-05-13 Bell Telephone Labor Inc Tandem arrays of in-phase couplers
JPS57115731U (enrdf_load_stackoverflow) * 1981-01-07 1982-07-17
JPS57151018U (enrdf_load_stackoverflow) * 1981-03-17 1982-09-22
US4777458A (en) * 1985-04-02 1988-10-11 Gte Telecomunicazioni S.P.A. Thin film power coupler
US20090195440A1 (en) * 2008-02-01 2009-08-06 Viasat, Inc. Highly integrated circuit architecture

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3660783A (en) * 1971-01-21 1972-05-02 Merrimac Research And Dev Co Signal splitting network wherein an output from second coupler is fed back to isolated part of first coupler
BE792560A (fr) * 1971-12-15 1973-03-30 Western Electric Co Reseaux de couplage de large bande
US3761843A (en) * 1972-05-16 1973-09-25 Merrimac Ind Inc Four port networks synthesized from interconnection of coupled and uncoupled sections of line lengths
JPS5639563B2 (enrdf_load_stackoverflow) * 1974-05-10 1981-09-14
US3879689A (en) * 1974-06-21 1975-04-22 Bell Telephone Labor Inc Matched phase shifter
JPS58165083U (ja) * 1982-04-27 1983-11-02 シ−アイ化成株式会社 排水枡
AT397323B (de) * 1989-10-23 1994-03-25 Alcatel Austria Ag Hochfrequenzfilter mit speziellem wickeldraht
US5461349A (en) * 1994-10-17 1995-10-24 Simons; Keneth A. Directional coupler tap and system employing same
US6806789B2 (en) * 2002-01-22 2004-10-19 M/A-Com Corporation Quadrature hybrid and improved vector modulator in a chip scale package using same
US7190240B2 (en) * 2003-06-25 2007-03-13 Werlatone, Inc. Multi-section coupler assembly
US6972639B2 (en) * 2003-12-08 2005-12-06 Werlatone, Inc. Bi-level coupler
GB2466028A (en) * 2008-12-08 2010-06-09 Univ Cardiff High frequency measurement system
US8392495B2 (en) * 2009-02-09 2013-03-05 Associated Universities, Inc. Reflectionless filters
WO2015199895A1 (en) 2014-06-25 2015-12-30 Associated Universities, Inc. Sub-network enhanced reflectionless filter topology
GB2529903A (en) * 2014-09-08 2016-03-09 Univ College Cork Nat Univ Ie IQ signal generator system and method
JP6652970B2 (ja) 2014-11-05 2020-02-26 アソシエイテッド ユニバーシティーズ，インコーポレイテッド 伝送線路無反射フィルタ
US10374577B2 (en) 2015-10-30 2019-08-06 Associated Universities, Inc. Optimal response reflectionless filters
US10530321B2 (en) 2015-10-30 2020-01-07 Associated Universities, Inc. Deep rejection reflectionless filters
WO2017074777A1 (en) 2015-10-30 2017-05-04 Associated Universities, Inc. Optimal response reflectionless filters
CN110474608B (zh) * 2019-09-03 2022-10-25 中国电子科技集团公司第三十八研究所 一种基于变压器的宽带正交相位产生网络

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB413621A (en) * 1932-10-11 1934-07-19 Ericsson Telefon Ab L M Improvements in electric filter circuits
US2263461A (en) * 1938-07-21 1941-11-18 Lorenz C Ag Carrier frequency communication exchange system
US2975381A (en) * 1957-02-21 1961-03-14 Raytheon Co Duplexers

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2922123A (en) * 1957-02-26 1960-01-19 Seymour B Cohn Directional filters for strip-line transmissions systems
DE1146559B (de) * 1960-09-27 1963-04-04 Siemens Ag Richtkoppler, bestehend aus einem aeusseren Schirm und zwei im Inneren dieses Schirmes angeordneten Innenleitern
US3184691A (en) * 1961-11-29 1965-05-18 Bell Telephone Labor Inc Branching hybrid coupler network useful for broadband power-dividing, duplexing and frequency separation
US3319190A (en) * 1962-07-02 1967-05-09 Dielectric Products Engineerin Electromagnetic wave coupling devices
US3252113A (en) * 1962-08-20 1966-05-17 Sylvania Electric Prod Broadband hybrid diplexer
US3237130A (en) * 1963-04-17 1966-02-22 Emerson Electric Co Four-port directional coupler with direct current isolated intermediate conductor disposed about inner conductors

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB413621A (en) * 1932-10-11 1934-07-19 Ericsson Telefon Ab L M Improvements in electric filter circuits
US2263461A (en) * 1938-07-21 1941-11-18 Lorenz C Ag Carrier frequency communication exchange system
US2975381A (en) * 1957-02-21 1961-03-14 Raytheon Co Duplexers

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3506932A (en) * 1968-02-28 1970-04-14 Bell Telephone Labor Inc Quadrature hybrid coupler
US3605044A (en) * 1968-11-18 1971-09-14 Bell Telephone Labor Inc Filter structures using bimodal, bisymmetric networks
US3576505A (en) * 1969-10-27 1971-04-27 Bell Telephone Labor Inc Transformer hybrid coupler having arbitrary power division ratio
US3723914A (en) * 1972-01-26 1973-03-27 J Cappucci Lumped constant quadrature coupler with improved parasitic suppression
US3723913A (en) * 1972-05-30 1973-03-27 Bell Telephone Labor Inc Quadrature hybrid coupler using one-port, linear circuit elements
US3869585A (en) * 1972-12-19 1975-03-04 Lorch Electronics Corp Asymmetric quadrature hybrid couplers
US3883827A (en) * 1974-05-02 1975-05-13 Bell Telephone Labor Inc Tandem arrays of in-phase couplers
JPS57115731U (enrdf_load_stackoverflow) * 1981-01-07 1982-07-17
JPS57151018U (enrdf_load_stackoverflow) * 1981-03-17 1982-09-22
US4777458A (en) * 1985-04-02 1988-10-11 Gte Telecomunicazioni S.P.A. Thin film power coupler
US20090195440A1 (en) * 2008-02-01 2009-08-06 Viasat, Inc. Highly integrated circuit architecture
US8044845B2 (en) * 2008-02-01 2011-10-25 Viasat, Inc. Highly integrated circuit architecture

Also Published As

Publication number Publication date
GB1159367A (en) 1969-07-23
DE1541483B2 (de) 1971-04-01
US3452301A (en) 1969-06-24
US3514722A (en) 1970-05-26
DE2000065A1 (de) 1971-07-29
JPS4841057B1 (enrdf_load_stackoverflow) 1973-12-04
DE1541483A1 (de) 1969-10-09
DE2000065B2 (de) 1972-03-30
GB1297779A (enrdf_load_stackoverflow) 1972-11-29

Similar Documents

Publication Publication Date Title
US3452300A (en) Four port directive coupler having electrical symmetry with respect to both axes
US5155724A (en) Dual mode diplexer/multiplexer
Bell L-resonator bandstop filters
US4126837A (en) Impedance element and band-rejection filter using the same
Levy A new class of distributed prototype filters with applications to mixed lumped/distributed component design
US3484724A (en) Transmission line quadrature coupler
US3573671A (en) Lattice-type filters employing mechanical resonators having a multiplicity of poles and zeros
US3559108A (en) Coupler switches
CN104078726B (zh) 并联型单侧椭圆函数传输线滤波器
CN114464973B (zh) 基于中心频率连续可调的可重构滤波衰减器
US3882432A (en) RF broadband transmission line impedance matching transformer pair for less than 4 to 1 impedance transformations
US4121180A (en) Broadband directional coupler
Wada et al. Design of a bandpass filter with multiple attenuation poles based on tapped resonators
CN105932378A (zh) 一种带宽可控的平面可调带通-带阻滤波器
US2724806A (en) Electromagnetic wave hybrid junction coaxial transmission line structures
US3605044A (en) Filter structures using bimodal, bisymmetric networks
CN113346861A (zh) 一种全开路枝节传输线带宽可调无反射滤波器
US3231837A (en) All-pass transformer coupling network utilizing high frequency and low frequency transformers in parallel connection
CN104078727B (zh) 串联型单侧椭圆函数传输线滤波器
US3551855A (en) Impedance transformer
Yang et al. Compact and high-performance low-temperature co-fired ceramic balun filter using the hybrid resonator and symmetric four-port network
Kim et al. A design of unequal termination impedance power divider with filtering and out-of-band suppression characteristics
GB1053155A (enrdf_load_stackoverflow)
Padmavathi et al. Analysis and design of reflectionless filters for c band applications
US3504304A (en) Wideband hybrid ring network