US3801936A - Miniaturized yig band-pass filter having defined damping poles - Google Patents

Miniaturized yig band-pass filter having defined damping poles Download PDF

Info

Publication number
US3801936A
US3801936A US00283202A US3801936DA US3801936A US 3801936 A US3801936 A US 3801936A US 00283202 A US00283202 A US 00283202A US 3801936D A US3801936D A US 3801936DA US 3801936 A US3801936 A US 3801936A
Authority
US
United States
Prior art keywords
yig
filter
band
pass filter
coupling
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
US00283202A
Other languages
English (en)
Inventor
P Roschmann
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.)
US Philips Corp
Original Assignee
US Philips 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
Priority claimed from DE19712142748 external-priority patent/DE2142748C3/de
Application filed by US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US3801936A publication Critical patent/US3801936A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01PWAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P1/00Auxiliary devices
    • H01P1/20Frequency-selective devices, e.g. filters
    • H01P1/215Frequency-selective devices, e.g. filters using ferromagnetic material
    • H01P1/218Frequency-selective devices, e.g. filters using ferromagnetic material the ferromagnetic material acting as a frequency selective coupling element, e.g. YIG-filters

Definitions

  • the microwave range in which the coupling structure consists of, for exam le, crossed coaxial inner conduc- [21] Appl 283202 tors in an external mggnet circuit which are semicircularly bent over the YIG elements, the coupling struc- [30] For i n A li ti P i it D m ture for the YlG resonators being arranged in a filter Aug. 26, 1971 Germany 2142748 body which is made for exampiei copper brass such that the coaxial supply conductors for coupling 52 US. Cl. 333/73 0, 333/83 R the YIG resonators e adjaceml arranged and are 51 Int. Cl.
  • the invention relates to a miniaturized YIG bandpass filter, comprising damping poles in order to achieve high selectivity in the microwave range, in which the coupling structure includes crossed coaxial inner conductors in an external magnetic circuit which are semicircularly bent over the YIG element.
  • ferrimagnetic'resonance in ferrite bodies; use is preferably made of yttrium-iron-garnet or similar YIG monocrystals, for example, substituted with Ga, which have very small resonance line widths and hence high resonance qualities.
  • the resonant frequency of the ferrimagnetic resonance is determined only by the strength of a static or quasi'static magnetizing field, the absolute dimensions of the ferrimagnetic resonator as opposed to conventional microwave filters with line or cavity resonators are of no importance in the first instance; use is preferably made of polished balls having typical diameters of between 0.3 and 1 mm.
  • YIG resonators can be used to good advantage so as to realize very small filters; in particular, very small permanently tuned or mechanically tunable filters can be manufactured by means of permanent magnets.
  • These properties are particularly'important for the miniaturized microwave circuits in the strip conductor technique (microstrip) which are manufactured by photoetching and which are being applied in increasing numbers.
  • Strip conductor substrates are generally made of ceramic and have a dielectric constant e of between 9 and 16. Consequently, a reduction of i.e., approximately a factor 3 4; moreover, ignoring the substrate thickness of between 0.2 and 0.6 mm, the strip conductor circuits are only two-dimensional. Due to the comparatively high conduction losses in strip conductors, conventional line resonators in this tech-- e is produced,
  • YIG filters can in principle be realized with structural dimensions which are compatible with the strip conductor technique.
  • the invention had for its object to provide, by means of YIG resonators, low-loss, narrow band bandpass filters of small volume which can be readily incorporated in a microstrip circuit without taking in too much space, and having defined damping poles and a very large slope steepness of their characteristic curve.
  • the filter prefferably inserted in a strip conductor circuit as a complete structural compo: nent similar to, for example, diodes or transistors.
  • the slope steepness of a filter increases as the number of resonant circuits used increases.
  • methods are also known how to produce defined damping poles on the filter curve to increase the slope steepness (known methods: Zobel elements, Cauer elements, elliptically coupled filters, n-path filters). The use of this technique reduces the number of resonant circuits required for a given damping of a filter, thus offering substantial savings as regards money and structural dimensions.
  • a two-circuit band-pass filter with two damping poles can have a slope steepness which corresponds to that of a three or four-circuit straight-coupling filter (Tchebyscheff, Butterworth), and the losses in the band-pass range are even smaller.
  • These filters are particularly suitable if the image frequency of the desired intermediate frequency is to be suppressed in an RF mixer the distance between the band-pass centre frequency and the pole frequency must then be equal to twice the intermediate frequency.
  • a band-pass filter with two well defined damping poles of its characteristic curve is'achieved in that the coupling structure for the YIG resonators in a filter body which is made of, for example, copper or brass, is arranged such that the coaxial supply conductors for coupling the first and for coupling the last YIG resonator are adjacently arranged and are magnetically coupled to each other in filters comprising an even number of YIG resonators or, in the case of filters comprising an odd number of YIG resonators, the coaxial supply conductor for coupling the first YIG resonator is magnetically coupled to the conductor for coupling the last YIG resonator.
  • FIG. 1 shows in cross-section a two-stage Y-IG bandpass filter component
  • FIG. 2 is a perspective view of the embodiment of FIG. 1 comprising magnets
  • FIG. 3 is a diagrammatic plan view of the embodi ment of FIG. I, 1
  • FIG. 4 shows band-pass filter curves
  • FIG. 5 shows a cross-section through a YIG filter with magnetic coupling
  • FIG. 6 is a diagrammatic plan view of the embodiment of FIG. 5,
  • FIG. 7 is a cross-sectional view of a further embodiment
  • FIG. 8 is a diagrammatic view of a tunable embodiment with magnets. J
  • the coaxial inner conductor 2 for the supply are fed out of the filter block 1 such that they are adjacently arranged, preferably in parallel, at a distance of approximately 0.5 to 1 mm from each other.
  • the filter body which is mounted in a permanent magnet is first built into a measuring adapter and the YIG balls 3 are adjusted according to the frequency wobbling method by means of holders 3'.
  • the filter component thus obtained is connected to the strip conductor circuit supported on a substrate 5 which is provided with a grounded plate 9 and appropriate paspling loops 4, fixing leaf spring 6, and screw 7.
  • FIG. 3 is a perspective view of the filter component with magnets, inthis case a permanent magnet circuit, comprising a yoke 10 and permanent magnets 11.
  • the connection of the magnet to the filter body can be effected by screwing, or by bonding or soldering.
  • a method of connecting the filter component in a strip conductor substrate is shown in FIG. 3: the fixing spring 6 is screwed to a projection I5 of the filter body 1 by means of a screw 7, the spring 6 then pressing 6 then pressing on the substrate (FIG. 3), thus producing a counter pressure.
  • the coaxial supply conductors 2 can be connccted in a conductive manner to the strip conductor 8 by soldering or bonding.
  • the supply conductors 2 which are magnetically coupled to the YIG resonators are also coupled to each other. The principle will be described with reference to FIG. 4.
  • the transmission curve 12 which is denoted by a signal passing through a broken line represents the amplitude behaviour of a straight-coupled band-pass filter, as a function of the frequency; line 13 shows the transmission a introduced by the magnetic coupling of the supply conductors (which can be measured, for example, when the YIG balls are removed from the filter body).
  • Curve 14 is a resulting band-pass filter curve with damping poles.
  • the pole frequencies f and f are situated at the intersections of lines 12 and 13 (interference); at these intersections the signal transmitted by the YIG resonators and the signal (a transmitted by the magnetic coupling of the supply conductors cancel each other.
  • the damping poles are situated between 65 dB and 70dB, determined by minor phase errors, so that the condition of equal amplitudes in the case of opposed phase does not occur simultaneously.
  • the distance from the pole frequenciesf and f to the centre frequency f can be symmetrically shifted; starting from the 3 dB band width (A f dB) of the filter, values (f,, f,) of approximately f m to M B) p n J1 chie e thi h. 92 T? sponcls to a coupling level a of dB to approximately 55 dB.
  • the interference required for producing the damping poles can occur symmetrically on both filter flanks only if the signal frequencies f f 2 f0), transmitted by the filter and situated about f0 below and above the pass frequency range, have approximately the same phase or a phase position which is shifted a mult ipl egf 2 11 with respect to each other.
  • the phase position for signals fgfo generally amounts to a multiple of 1r which is about equal to the number of filter circuits: the above phase condition (multiple of 2 1r is satisfied only if there is an even number of filter circuits; in that case the magnetic coupling a between the filter supply conductors can be effected as described in the foregoing.
  • the magnetic coupling a In the case of an odd number of filter circuits, the magnetic coupling a must be effected, for example, between the supply conductor for the (external) coupling of the first resonator and the inner coupling conductor 2' for the (inner, related to the filter) coupling of the last resonator.
  • FIGS. 5 and 6 show an embodiment which results from the omission of the bar 15.
  • the distance a between the filter supply conductors 2 as well as the distance b between the filter bodies and the conductor side of the microstrip substrate influence the level a of the directly coupled signal.
  • FIG. 7 shows the principle of an embodiment which enables continuous adjustment of the coupling level a the two supply conductors being coupled through the slit 16; the coupling can be varied by means of a displaceable shutter 17. Other similar devices utilizing screws are alternatively possible.
  • FIGS. 6 and 8 show a further method of connecting the filter body to the microstrip substrate.
  • the filter which is arranged below the substrate is secured by means of the screws 18 on the circuit side of the substrate.
  • FIG. 8 shows the required threaded holes 19, for example, in the magnet yoke.
  • FIG. 8 also shows a simple possibility of tuning the centre frequency of the filter by screwing the screw 20, made of a magnetic material, further into or out of the hole so that a magnetic shunt is produced which more or less decreases the field in the range of the filter, and hence the resonant frequency.
  • a coil 21 in the magnetic circuit an electronic (additional) tuning can also be achieved which is advantageous, for example, for an electronically controlled frequency readjustment.
  • the generation of pole frequencies is not restricted to the special cases described here, but the required measures can also be realized in known electronically tunable YIG filters in accordance with the described embodiments.
  • a miniaturized YIG band-pass filter having defined damping poles comprising: an even number of ferrimagnetic YIGresonators, a filter body of electroconductive non-magnetizable material, a corresponding number of chambersformed in said body for receiving said YIG resonators, respectively, the first and the last chamber being arranged adjacent each other and interconnected by a coupling aperture, two parallel passages leading from said first and last chambers respectively, to an external surface of said body, an input and output coupling structure including coaxial supply conductors passing through said passages and being magnetically coupled to one side of said YIG elements, a crossed inner conductor passing through said coupling aperture and being magnetically coupled to another side of said YIG elements, and an open space formed in said body between predetermined portions of said supply conductor to produce an additional coupling therebetween thereby forming damping poles in the filter curve.
  • a YIG bandpass filter as claimed in claim 1 characterized in that an adjustable magnetic shunt is provided for the external magnetic field for the YIG resonators.
  • a YIG band-pass filter as claimed in claim 1 characterized in that the external magnetic circuit can be electronically adjusted by means of a coil.
  • a band-pass filter according to claim 4 further including an additional chamber with a YlG resonator, and portions of said crossed inner conductor being directed against side opening to introduce coupling between a supply conductor of one YlG resonator and the inner conductor near the other YlG resonator.

Landscapes

  • Control Of Motors That Do Not Use Commutators (AREA)
US00283202A 1971-08-26 1972-08-23 Miniaturized yig band-pass filter having defined damping poles Expired - Lifetime US3801936A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712142748 DE2142748C3 (de) 1971-08-26 Miniaturisiertes YIG-BandpaBfilter mit Dämpfungspolen

Publications (1)

Publication Number Publication Date
US3801936A true US3801936A (en) 1974-04-02

Family

ID=5817838

Family Applications (1)

Application Number Title Priority Date Filing Date
US00283202A Expired - Lifetime US3801936A (en) 1971-08-26 1972-08-23 Miniaturized yig band-pass filter having defined damping poles

Country Status (4)

Country Link
US (1) US3801936A (enrdf_load_stackoverflow)
JP (1) JPS5340062B2 (enrdf_load_stackoverflow)
FR (1) FR2150454B1 (enrdf_load_stackoverflow)
GB (1) GB1389126A (enrdf_load_stackoverflow)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4131987A (en) * 1976-08-02 1979-01-02 U.S. Philips Corporation Method of producing a microwave filter comprising a body of gyromagnetic material and a source of a prepolarizing magnetic field whose resonant frequency is a predetermined function of the temperature
US4334201A (en) * 1978-09-21 1982-06-08 Tektronix, Inc. YIG Bandpass filter interconnected by means of longitudinally split coaxial transmission lines
US4465974A (en) * 1980-03-03 1984-08-14 Raytheon Company Apparatus for measuring magnetic field characteristics of magnetic materials
EP0173291A3 (en) * 1984-08-30 1988-05-04 Sony Corporation Apparatus for varying the magnetic field for a magnetic resonance element
US4988959A (en) * 1989-10-31 1991-01-29 Avantek, Inc. YIG tuned oscillator using composite feedback
US5086506A (en) * 1987-08-14 1992-02-04 General Electric Company Radio trunking fault detection system with power output monitoring and on-air monitoring
CN114938211A (zh) * 2022-07-25 2022-08-23 西南应用磁学研究所(中国电子科技集团公司第九研究所) 一种驱动电路及由其组成的小型化旋磁滤波器组件
CN115939708A (zh) * 2023-03-10 2023-04-07 成都威频科技有限公司 一种上下耦合宽带宽可调带通滤波器
CN116073098A (zh) * 2023-03-03 2023-05-05 成都威频科技有限公司 一种超宽带可调带通滤波器

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3368169A (en) * 1964-05-08 1968-02-06 Stanford Research Inst Tunable bandpass filter
US3400343A (en) * 1965-02-23 1968-09-03 Physical Electronics Lab Tunable bandpass filter
US3435385A (en) * 1966-03-04 1969-03-25 Loral Corp Electronically tunable yig filter having an electronically variable bandwidth

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3368169A (en) * 1964-05-08 1968-02-06 Stanford Research Inst Tunable bandpass filter
US3400343A (en) * 1965-02-23 1968-09-03 Physical Electronics Lab Tunable bandpass filter
US3435385A (en) * 1966-03-04 1969-03-25 Loral Corp Electronically tunable yig filter having an electronically variable bandwidth

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4131987A (en) * 1976-08-02 1979-01-02 U.S. Philips Corporation Method of producing a microwave filter comprising a body of gyromagnetic material and a source of a prepolarizing magnetic field whose resonant frequency is a predetermined function of the temperature
US4334201A (en) * 1978-09-21 1982-06-08 Tektronix, Inc. YIG Bandpass filter interconnected by means of longitudinally split coaxial transmission lines
US4465974A (en) * 1980-03-03 1984-08-14 Raytheon Company Apparatus for measuring magnetic field characteristics of magnetic materials
EP0173291A3 (en) * 1984-08-30 1988-05-04 Sony Corporation Apparatus for varying the magnetic field for a magnetic resonance element
US5086506A (en) * 1987-08-14 1992-02-04 General Electric Company Radio trunking fault detection system with power output monitoring and on-air monitoring
US4988959A (en) * 1989-10-31 1991-01-29 Avantek, Inc. YIG tuned oscillator using composite feedback
CN114938211A (zh) * 2022-07-25 2022-08-23 西南应用磁学研究所(中国电子科技集团公司第九研究所) 一种驱动电路及由其组成的小型化旋磁滤波器组件
CN116073098A (zh) * 2023-03-03 2023-05-05 成都威频科技有限公司 一种超宽带可调带通滤波器
CN116073098B (zh) * 2023-03-03 2023-08-08 成都威频科技有限公司 一种超宽带可调带通滤波器
CN115939708A (zh) * 2023-03-10 2023-04-07 成都威频科技有限公司 一种上下耦合宽带宽可调带通滤波器
CN115939708B (zh) * 2023-03-10 2023-06-02 成都威频科技有限公司 一种上下耦合宽带宽可调带通滤波器

Also Published As

Publication number Publication date
DE2142748A1 (de) 1973-03-08
FR2150454A1 (enrdf_load_stackoverflow) 1973-04-06
JPS5340062B2 (enrdf_load_stackoverflow) 1978-10-25
FR2150454B1 (enrdf_load_stackoverflow) 1978-10-27
JPS4831037A (enrdf_load_stackoverflow) 1973-04-24
GB1389126A (en) 1975-04-03
DE2142748B2 (de) 1976-02-05

Similar Documents

Publication Publication Date Title
US6538532B2 (en) Magnetically coupled series-tuned air coil resonators having very low C/L ratios to achieve higher QL, lower insertion loss and improved out-of-band rejection
US3728731A (en) Multi-function antenna coupler
IE53573B1 (en) Microwave receiving device
US3801936A (en) Miniaturized yig band-pass filter having defined damping poles
CN115275546A (zh) 一种3GHz-8GHz的YIG可调谐带阻滤波器
US3286201A (en) Ferrite circulator having three mutually coupled coils coupled to the ferrite material
US3368169A (en) Tunable bandpass filter
US4020429A (en) High power radio frequency tunable circuits
US3671888A (en) Wide band stop band filter including a ferrite region biased by a graded magnetic field
CN102544654A (zh) 一种变容管电可调微带滤波器
US3335374A (en) Lumped element y circulator
CN114914647A (zh) 一种基于铁氧体材料的可调谐宽带带阻滤波器
CA2270616C (en) A microwave diplexer arrangement
US3268838A (en) Magnetically tunable band-stop and band-pass filters
US3113278A (en) Microwave power limiter utilizing detuning action of gyromagnetic material at high r-f power level
US3611197A (en) Yig resonator microstrip coupling device
US2518092A (en) Ultra high frequency band-pass circuits
CN115332745B (zh) 一种宽阻带yig可调谐带阻滤波器
US3546637A (en) Tunable microstrip band pass filter utilizing gyromagnetic material at the junction of two conductive loops
US3480888A (en) Electronically tuned filter
JPH0537202A (ja) アジル型マイクロ波フイルタ
US6809615B2 (en) Band-pass filter and communication apparatus
CN115863946A (zh) 一种高隔离度可调带通滤波器
US20180331405A1 (en) Dielectric filter unit and communication device
US3913039A (en) High power yig filter