WO2010038215A1 - A cylindrical microwave resonator - Google Patents

A cylindrical microwave resonator Download PDF

Info

Publication number
WO2010038215A1
WO2010038215A1 PCT/IB2009/054311 IB2009054311W WO2010038215A1 WO 2010038215 A1 WO2010038215 A1 WO 2010038215A1 IB 2009054311 W IB2009054311 W IB 2009054311W WO 2010038215 A1 WO2010038215 A1 WO 2010038215A1
Authority
WO
WIPO (PCT)
Prior art keywords
tubular member
thermal elongation
order
different
variation
Prior art date
Application number
PCT/IB2009/054311
Other languages
French (fr)
Inventor
Andrea De Marchi
Original Assignee
Politecnico Di Torino
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 Politecnico Di Torino filed Critical Politecnico Di Torino
Publication of WO2010038215A1 publication Critical patent/WO2010038215A1/en

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/64—Heating using microwaves
    • H05B6/70—Feed lines
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P7/00—Resonators of the waveguide type
    • H01P7/06—Cavity resonators
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/64—Heating using microwaves
    • H05B6/6402—Aspects relating to the microwave cavity

Definitions

  • the present invention relates in general to microwave resonators, in particular for the manufacture of oscillators.
  • the invention relates to a cylindrical microwave resonator, of the type comprising: a cylindrical tubular member made of metal material, and closure means likewise made of metal material and associated with the tubular member so as to define in the inside thereof a cylindrical cavity resonating at a predetermined frequency; and in which said closure means have a thermal elongation coefficient different from that of the tubular member so as to reduce the variation in the resonance frequency of the cavity upon variation of the temperature.
  • a microwave resonator of this type is described for example in "A Novel Configuration for Microwave Resonator with Zero Temperature-Coefficient", by M. Long, A. S. Gupta, F. L. Walls, Frequency Control Symposium 2007 joint with the 21st European Frequency and Time Forum, IEEE International, May 29- June 1 2007, pages 1020-1022.
  • FIG. 1 of the accompanying drawings A cylindrical microwave resonator of the type described in this document is schematically shown in Figure 1 of the accompanying drawings, where it is denoted overall by 1.
  • This resonator comprises a cylindrical tubular member 2, for example made of molybdenum with a silver-coated inner surface, and a pair of closing caps 3, for example made of silver aluminium.
  • These caps each have a respective cylindrical shank 3 a which extends inside a respective end of the tubular member 2 so as to define together therewith a cylindrical cavity 5, having a length 1 and diameter D, resonating at a predetermined frequency.
  • the closing caps 3 are identical to each other and their shanks have a thermal elongation coefficient different from that of the tubular member 2 so as to reduce the variation ⁇ v in the resonance frequency v of the cavity 5 upon variation of the temperature T.
  • ⁇ l/1 ⁇ ( ⁇ T) + ⁇ ( ⁇ T) 2 + ⁇ ( ⁇ T) 3 + ... (1)
  • ⁇ , ⁇ , ⁇ , ... are the thermal elongation coefficients of the first order, second order, third order, etc.
  • One object of the present invention is to propose a cylindrical microwave resonator of the type specified above, which is able to achieve a better frequency stability compared to the known solution described above.
  • a cylindrical microwave resonator of the type defined initially characterized in that the abovementioned closure means comprise at least two cap portions made of different metal materials, having respective thermal elongation coefficients of the first and second order and respective axial lengths such as to compensate at least in part for the thermal elongation coefficients of the first and second order of the tubular member.
  • Figure 1 already described, shows the structure of a cylindrical microwave resonator according to the prior art
  • Figure 2 shows the variation in frequency upon variation of the temperature in a resonator according to the prior art of the type shown in Figure 1 ;
  • Figure 3 is a view, partially sectioned axially, of a cylindrical microwave resonator according to the present invention.
  • Figures 4 and 5 are graphs which show the variation in frequency as a function of the variation of the temperature in a resonator according to the present invention.
  • Figures 6 to 8 are partially sectioned views of three further embodiments of resonators according to the invention.
  • ⁇ v/v k ⁇ , ( ⁇ T) 2 (2), where k is a constant.
  • the equation (3) shows that a suitable selection of the materials may result in the zeroing or even a negative value of the second term in this equation.
  • the present invention arises from this observation, namely that it is possible to ensure that the second term in the equation (3) reduces substantially the ⁇ v/v and even zeroes it completely or nearly so.
  • the invention consists essentially in having recognized that it is possible to "synthesize" or determine the thermal behaviour of the closing caps of the resonator in such a way as to improve substantially the stability of the frequency upon variation of the temperature, compared to the prior art solution described above.
  • FIG. 3 shows a first embodiment of a microwave resonator according to the invention.
  • parts and elements already described have been assigned again the same reference numbers and/or letters.
  • the resonator 1 comprises two end caps 3, which are identical to each other, with respective cylindrical shanks 3 a which each have a first and a second axial portion cl e c2, adjacent to one another, made with different metal materials, having respective thermal elongation coefficients of the first order and second order ⁇ cl , ⁇ c i and ⁇ c2 , ⁇ c2 and respective axial lengths l cl /2 and l c2 /2 such as to compensate at least in part for the thermal elongation coefficients of the first and second orders ⁇ p, P D of the tubular member 2.
  • the tubular member 2 may be made for example with tungsten, preferably containing a percentage of nickel and iron, for example about 2% by weight of nickel and 1% by weight of iron.
  • the tubular member 2 could be made with molybdenum. In any case it is convenient for the inner surface of the tubular member 2 to be silver-coated.
  • the portions cl of the shanks 3 a of the end caps 3 may be conveniently made using an austenitic steel, for example AISI 304, while the portions c2 may be made of copper.
  • the dimensions 1 and D of the cavity 5 are determined in a manner known per se on the basis of the desired resonance frequency.
  • ⁇ g 2ll2>
  • ⁇ c ⁇ iDI ⁇
  • ⁇ cs the overall thermal elongation coefficient of the first order for the shanks 3 a of the end caps of the resonator
  • ⁇ cs the overall thermal elongation coefficient of the second order for said shanks 3 a.
  • ⁇ X D e P D are the thermal elongation coefficients of the first and second order of the tubular member 2.
  • Equation (5) shown above expresses the condition for zeroing the variation in frequency upon variation of the temperature, while the following equations express the relations existing between the thermal elongation coefficients and the lengths of the portions cl and c2 of the end caps of the resonator.
  • Figures 6 to 8 show alternative embodiments of a resonator according to the present invention.
  • the resonator comprises a tubular member 2 which is closed at one end by a cap 3 similar to those described above with reference to Figure 3.
  • the other end of the tubular member 2 is closed by a wall 2a made with a material which has substantially the same thermal elongation as this tubular member.
  • the end wall 2a may be integral with the tubular member or made separately and joined to this tubular member in one of the various ways known per se.
  • the resonator 1 comprises two end caps 3 and 4, the shanks 3 a and 4a of which are each made using a single material.
  • the materials of these shanks however, have thermal elongation characteristics which are different from one another.
  • the dimensions in this case are determined substantially in the manner described above, where the lengths l cl and l c2 represent the respective lengths of the two shanks 3 a and 4a.
  • Figure 8 shows an embodiment in which the resonator 1 has an end cap 3 which is similar to the caps of the version according to Figure 3 or the version according to Figure 6 and therefore is formed with two axial portions cl, c2 made of materials having different thermal elongation characteristics.
  • the resonator 1 according to Figure 8 has a further end cap 4, the shank of which, with a length l c3 , is made with a material having thermal elongation characteristics different from those of the portions cl and c2 of the cap 3.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Inorganic Insulating Materials (AREA)

Abstract

The microwave resonator (1) comprises a tubular member (2) made of metal material, and closing caps (3; 3, 4), likewise made of metal material, associated with the tubular member (2) so as to define in the inside thereof a cylindrical cavity (5) resonating at a predetermined frequency. The closing caps (3; 3, 4) have a thermal expansion coefficient different from that of the tubular member (2) so as to reduce the variation in the resonance frequency (v) of the cavity (5) upon variation of the temperature (T). These closing caps (3; 3, 4) comprise at least two portions (c1, c2) made of different metal materials, having respective thermal elongation coefficients of the first and second order (α1, β1; α2, β2) different from one another, and respective axial lengths (1c1, 1c2), such as to compensate at least in part for the thermal elongation coefficients of the first and second order (αD, βD) of the tubular member (2).

Description

A cylindrical microwave resonator
The present invention relates in general to microwave resonators, in particular for the manufacture of oscillators.
More specifically the invention relates to a cylindrical microwave resonator, of the type comprising: a cylindrical tubular member made of metal material, and closure means likewise made of metal material and associated with the tubular member so as to define in the inside thereof a cylindrical cavity resonating at a predetermined frequency; and in which said closure means have a thermal elongation coefficient different from that of the tubular member so as to reduce the variation in the resonance frequency of the cavity upon variation of the temperature.
A microwave resonator of this type is described for example in "A Novel Configuration for Microwave Resonator with Zero Temperature-Coefficient", by M. Long, A. S. Gupta, F. L. Walls, Frequency Control Symposium 2007 joint with the 21st European Frequency and Time Forum, IEEE International, May 29- June 1 2007, pages 1020-1022.
A cylindrical microwave resonator of the type described in this document is schematically shown in Figure 1 of the accompanying drawings, where it is denoted overall by 1. This resonator comprises a cylindrical tubular member 2, for example made of molybdenum with a silver-coated inner surface, and a pair of closing caps 3, for example made of silver aluminium. These caps each have a respective cylindrical shank 3 a which extends inside a respective end of the tubular member 2 so as to define together therewith a cylindrical cavity 5, having a length 1 and diameter D, resonating at a predetermined frequency. The closing caps 3 are identical to each other and their shanks have a thermal elongation coefficient different from that of the tubular member 2 so as to reduce the variation Δv in the resonance frequency v of the cavity 5 upon variation of the temperature T.
Upon variation of the temperature T by an amount ΔT, the length 1 of the cavity 5 varies correspondingly by an amount Δl, as expressed by the equation:
Δl/1 = α (ΔT) + β (ΔT)2 + γ (ΔT)3 + ... (1) where α, β, γ, ... are the thermal elongation coefficients of the first order, second order, third order, etc.
A variation in the length 1 of the cavity 5, caused by a variation of the temperature T, in turn causes a variation in the frequency v. With the solution proposed in the abovementioned prior publication it is possible to offset or compensate in part for this variation in the frequency.
However, there is a considerable discrepancy between theory and experimental verification of the solution described in this publication so that the effective improvement in the frequency stability which can be achieved in practice is markedly less than that which is theoretically possible.
One object of the present invention is to propose a cylindrical microwave resonator of the type specified above, which is able to achieve a better frequency stability compared to the known solution described above.
This and other objects are achieved according to the invention with a cylindrical microwave resonator of the type defined initially, characterized in that the abovementioned closure means comprise at least two cap portions made of different metal materials, having respective thermal elongation coefficients of the first and second order and respective axial lengths such as to compensate at least in part for the thermal elongation coefficients of the first and second order of the tubular member.
Further characteristic features and advantages of the invention will become clear from the following detailed description provided purely by way of a non-limiting example, with reference to the accompanying drawings in which:
Figure 1, already described, shows the structure of a cylindrical microwave resonator according to the prior art;
Figure 2 shows the variation in frequency upon variation of the temperature in a resonator according to the prior art of the type shown in Figure 1 ;
Figure 3 is a view, partially sectioned axially, of a cylindrical microwave resonator according to the present invention;
Figures 4 and 5 are graphs which show the variation in frequency as a function of the variation of the temperature in a resonator according to the present invention; and
Figures 6 to 8 are partially sectioned views of three further embodiments of resonators according to the invention.
The present invention is based essentially on recognition of the fact that the authors of the aforementioned prior publication have essentially overlooked the effect of the quadratic term in the above equation (1), namely they have assumed β = γ = 0. According to this assumption, in the case of a resonator having the structure shown in Figure 1, the relative variation in the frequency upon variation of the temperature is essentially expressed by the following equation:
Δv/v = k α^, (ΔT)2 (2), where k is a constant.
As a result of this assumption, the theory expounded in the aforementioned publication leads one to assume that the progression of the variation in frequency Δv as a function of the variation in temperature ΔT has an essentially parabolic progression, as shown by the curved indicated by A in the graph of Figure 2.
In reality, if in the equation (1) the quadratic term is not negligible, the following expression is obtained for the variation in frequency Δv/v:
Figure imgf000004_0001
where etc and oto are the elongation coefficients of the first order of the shanks 3a and caps 3 and of the tubular member 2, respectively, and βc and βo are the thermal elongation coefficients of the second order thereof.
An examination of the equation (3) shows how, depending on the materials used, and therefore their thermal elongation coefficients, the variation in the frequency upon variation of the temperature may be very much greater than that which can be predicted using the equation (2) and may assume, for example, the progression of the parabola - indicated by B in Figure 2 - which is much "narrower" than that indicated by A.
On the other hand, the equation (3) shows that a suitable selection of the materials may result in the zeroing or even a negative value of the second term in this equation. The present invention arises from this observation, namely that it is possible to ensure that the second term in the equation (3) reduces substantially the Δv/v and even zeroes it completely or nearly so.
Based on the aforementioned observation, the invention consists essentially in having recognized that it is possible to "synthesize" or determine the thermal behaviour of the closing caps of the resonator in such a way as to improve substantially the stability of the frequency upon variation of the temperature, compared to the prior art solution described above.
Figure 3 shows a first embodiment of a microwave resonator according to the invention. In this figure parts and elements already described have been assigned again the same reference numbers and/or letters.
In the solution according to Figure 3, the resonator 1 comprises two end caps 3, which are identical to each other, with respective cylindrical shanks 3 a which each have a first and a second axial portion cl e c2, adjacent to one another, made with different metal materials, having respective thermal elongation coefficients of the first order and second order αcl, βci and αc2, βc2 and respective axial lengths lcl/2 and lc2/2 such as to compensate at least in part for the thermal elongation coefficients of the first and second orders αp, PD of the tubular member 2.
With reference to Figure 3, the tubular member 2 may be made for example with tungsten, preferably containing a percentage of nickel and iron, for example about 2% by weight of nickel and 1% by weight of iron. Alternatively, the tubular member 2 could be made with molybdenum. In any case it is convenient for the inner surface of the tubular member 2 to be silver-coated.
The portions cl of the shanks 3 a of the end caps 3 may be conveniently made using an austenitic steel, for example AISI 304, while the portions c2 may be made of copper.
By means of suitable selection of the materials of the portions cl and c2 and precise definition of their axial lengths it is possible to ensure that the variation Δv as a function of the variation in temperature ΔT assumes a progression in the manner of a cubic parabola, for example in accordance with the curve C shown in Figure 4, which corresponds to a condition where the thermal elongation coefficient of the second order βo of the tubular member 2 has also been substantially compensated for. The improvement in terms of frequency stability is evident compared to the progression of the curve B which, as shown in Figure 2, represents the most "realistic" progression which can be achieved with the solution according to the prior art.
Figure 4 and Figure 5 show - the latter on a smaller scale - the progression of a curve D which can be obtained with compensation of the thermal elongation coefficient of the second order of the tubular member 2 in the case where γ = 0 for all the metals used. If, instead, one takes into account the fact that the thermal elongation coefficients of the third order (γ) are not zero, the curve obtained is that indicated by C in Figure 4.
The dimensions of the resonator according to Figure 3 may be determined substantially as described below.
The dimensions 1 and D of the cavity 5 are determined in a manner known per se on the basis of the desired resonance frequency.
The equation (3) may then be rewritten as follows:
Δv/v
Figure imgf000006_0001
(4) where λg = 2ll2> , λc = τiDI χ , with for example ^ = 7.016 if the TE023 mode resonates in the cavity, and αcs is the overall thermal elongation coefficient of the first order for the shanks 3 a of the end caps of the resonator, and βcs is the overall thermal elongation coefficient of the second order for said shanks 3 a.
In the equation (4) <XD e PD are the thermal elongation coefficients of the first and second order of the tubular member 2.
From the equation (4), in order to obtain Δv = 0 the following is necessary:
Figure imgf000007_0001
Once the materials for the tubular member 2 and the caps 3 - for example the materials mentioned above - have been chosen, it is then merely required to determine the coefficients αcl, βcl and αC2, βC2 of the portions cl and c2 of the end caps as well as the associated lengths lcj and lc2 in the equation (4).
The values of these lengths may be easily determined on the basis of the following system of equations:
Figure imgf000007_0002
z = zi + z2 = {lc} +lc2)/l (6)
(l + z)aD - zaa = 0 (7)
Figure imgf000007_0003
zfic = ZlPcl +Z2fic2 (9)
The equation (5) shown above expresses the condition for zeroing the variation in frequency upon variation of the temperature, while the following equations express the relations existing between the thermal elongation coefficients and the lengths of the portions cl and c2 of the end caps of the resonator.
Figures 6 to 8 show alternative embodiments of a resonator according to the present invention.
In the variant according to Figure 6, the resonator comprises a tubular member 2 which is closed at one end by a cap 3 similar to those described above with reference to Figure 3. The other end of the tubular member 2 is closed by a wall 2a made with a material which has substantially the same thermal elongation as this tubular member. The end wall 2a may be integral with the tubular member or made separately and joined to this tubular member in one of the various ways known per se.
In the case of the solution according to Figure 6, the dimensions are determined substantially in the same way as described above for the variant according to Figure 3, with the lengths lcl and lc2 which represent the lengths of the portions cl and c2 of the shank of the cap 3, as shown in Figure 6 itself.
In the variant according to Figure 7, the resonator 1 comprises two end caps 3 and 4, the shanks 3 a and 4a of which are each made using a single material. The materials of these shanks, however, have thermal elongation characteristics which are different from one another. The dimensions in this case are determined substantially in the manner described above, where the lengths lcl and lc2 represent the respective lengths of the two shanks 3 a and 4a.
Finally, Figure 8 shows an embodiment in which the resonator 1 has an end cap 3 which is similar to the caps of the version according to Figure 3 or the version according to Figure 6 and therefore is formed with two axial portions cl, c2 made of materials having different thermal elongation characteristics. The resonator 1 according to Figure 8 has a further end cap 4, the shank of which, with a length lc3, is made with a material having thermal elongation characteristics different from those of the portions cl and c2 of the cap 3.
With the solution comprising three materials (cl, c2, c3) according to Figure 8 it is possible to compensate also for thermal elongation coefficient of the third order γ of the tubular member 2. Obviously, without affecting the principle of the invention, the embodiments and the constructional details may be greatly modified with respect to that described and illustrated purely by way of a non-limiting example, without thereby departing from the scope of the invention as defined in the accompanying claims.

Claims

1. Cylindrical microwave resonator ( 1 ), comprising a cylindrical tubular member (2) made of metal material, and closure means (3; 3, 4), likewise made of metal material, associated with the tubular member (2) so as to define in the inside thereof a cylindrical cavity (5) resonating at a predetermined frequency; said closure means (3; 3, 4) having a thermal expansion coefficient different from that of the tubular member (2), so as to reduce the variation in the resonance frequency (v) of the cavity (5) upon variation of the temperature (T); the resonator (1) being characterized in that said closure means (3; 3, 4) comprise at least two cap portions (cl, c2) made of different metal materials, having respective thermal elongation coefficients of the first and the second order (Ct1, P1; α2, p2) different from each other, and respective axial lengths (lcl, lc2), such as to compensate at least in part for the thermal elongation coefficients of the first and second order ((XD, PD) of the tubular member (2).
2. Microwave resonator according to Claim 1, in which the closure members comprise at least one cap (3) having a cylindrical shank (3 a) which extends inside one end of the tubular member (2) and has a first and a second axial portion (cl, c2) adjacent to one another, made with different metal materials having respective thermal elongation coefficients of the first and the second order ((X1, P1; α2, P2) different from one another, and respective axial lengths (lcl, I02), such as to compensate at least in part for the thermal elongation coefficients of the first and the second order (αo, PD) of the tubular member (2).
3. Microwave resonator according to Claim 2, in which the closure means comprise two caps (3, 4) as defined above, each having a respective cylindrical shank (3 a, 4a) which extends inside a respective end of the tubular member (2).
4. Microwave resonator according to Claim 1, in which the closure means comprise two caps (3, 4; see Figure 7) comprising respective cylindrical shanks (3a, 4a) extending each inside a respective end of the tubular member (2); said shanks (3a, 4a) being made each with a metal material different from that of the other one, said materials having respective thermal elongation coefficients of the first and the second order ((X1, P1; α2, β2) different from one another, and respective axial lengths (lcl, 1C2), such as to compensate at least in part for the thermal elongation coefficients of the first and the second order (do, βo) of the tubular member (2).
5. Microwave resonator according to Claim 1, in which the closure means comprise at least three cap portions (cl, c2, c3) having respective thermal elongation coefficients different from one another, and respective axial lengths, such as to compensate at least in part for the thermal elongation coefficients of the first, second and third order of the tubular member (2).
PCT/IB2009/054311 2008-10-03 2009-10-02 A cylindrical microwave resonator WO2010038215A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITTO2008A000728 2008-10-03
ITTO2008A000728A IT1391340B1 (en) 2008-10-03 2008-10-03 CYLINDRICAL MICROWAVE RESONATOR.

Publications (1)

Publication Number Publication Date
WO2010038215A1 true WO2010038215A1 (en) 2010-04-08

Family

ID=40849282

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2009/054311 WO2010038215A1 (en) 2008-10-03 2009-10-02 A cylindrical microwave resonator

Country Status (2)

Country Link
IT (1) IT1391340B1 (en)
WO (1) WO2010038215A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014075801A1 (en) * 2012-11-15 2014-05-22 Kathrein-Austria Ges.M.B.H. High frequency filter having frequency stabilization
CN113299610A (en) * 2021-05-21 2021-08-24 中国电子科技集团公司第二十九研究所 High-reliability packaging structure and packaging method for microwave part cover plate

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057772A (en) * 1976-10-18 1977-11-08 Hughes Aircraft Company Thermally compensated microwave resonator
CA1152169A (en) * 1982-08-25 1983-08-16 Adrian V. Collins Temperature compensated resonant cavity
US4521754A (en) * 1983-08-29 1985-06-04 International Telephone And Telegraph Corporation Tuning and temperature compensation arrangement for microwave resonators
DE4113302A1 (en) * 1991-04-24 1992-10-29 Ant Nachrichtentech Capacitively loaded microwave cavity resonator with temp. compensation - is frequency-stabilised by gap between stub and wall deformed centrally by thermal expansion of strap
US5691677A (en) * 1993-07-02 1997-11-25 Italtel Spa Tunable resonator for microwave oscillators and filters
US6169468B1 (en) * 1999-01-19 2001-01-02 Hughes Electronics Corporation Closed microwave device with externally mounted thermal expansion compensation element

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057772A (en) * 1976-10-18 1977-11-08 Hughes Aircraft Company Thermally compensated microwave resonator
CA1152169A (en) * 1982-08-25 1983-08-16 Adrian V. Collins Temperature compensated resonant cavity
US4521754A (en) * 1983-08-29 1985-06-04 International Telephone And Telegraph Corporation Tuning and temperature compensation arrangement for microwave resonators
DE4113302A1 (en) * 1991-04-24 1992-10-29 Ant Nachrichtentech Capacitively loaded microwave cavity resonator with temp. compensation - is frequency-stabilised by gap between stub and wall deformed centrally by thermal expansion of strap
US5691677A (en) * 1993-07-02 1997-11-25 Italtel Spa Tunable resonator for microwave oscillators and filters
US6169468B1 (en) * 1999-01-19 2001-01-02 Hughes Electronics Corporation Closed microwave device with externally mounted thermal expansion compensation element

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014075801A1 (en) * 2012-11-15 2014-05-22 Kathrein-Austria Ges.M.B.H. High frequency filter having frequency stabilization
US9673497B2 (en) 2012-11-15 2017-06-06 Kathrein-Austria Ges.M.B.H High frequency filter having frequency stabilization
CN113299610A (en) * 2021-05-21 2021-08-24 中国电子科技集团公司第二十九研究所 High-reliability packaging structure and packaging method for microwave part cover plate

Also Published As

Publication number Publication date
ITTO20080728A1 (en) 2010-04-04
IT1391340B1 (en) 2011-12-05

Similar Documents

Publication Publication Date Title
WO2010038215A1 (en) A cylindrical microwave resonator
Elliott et al. Particle trapping and banding in rapid colloidal solidification
EP2165416A1 (en) Mems resonators
CN106063027A (en) Method for compensating a temperature drift of a microwave filter
US20030193379A1 (en) Microwave filter having a temperature compensating element
Shi et al. Thermoelastic damping analysis model of transversely isotropic micro/nano-resonators based on dual-phase-lag heat conduction model and surface effect
Zhang et al. Nonlinear dynamic response of beam and its application in nanomechanical resonator
McFadden et al. Effect of surface free energy anisotropy on dendrite tip shape
CN102820505A (en) Miniaturization narrow-band filter
Soyalp et al. Ab initio investigations of phonons and thermodynamic properties of ScZn and YZn in the B2 structure
Flensberg Electron–vibron coupling in suspended nanotubes
EP2903083B1 (en) Microwave filter having a fine temperature drift tuning mechanism
Tan et al. Melting curve of iron up to 3600 kbar by statistical moment method
Indeitsev et al. On the influence of the microstructure on the stress-strain state of material
Kajikawa et al. Method for altering deformational characteristics of controlled-clearance piston-cylinders
Desai et al. Effect of built-in tension due to variation in temperature on natural frequency of graphene nano ribbon resonator
Suryanarayana Sturm-Liouville Eigenvalue problem for non-linear differential equations on a time scale
Olsen et al. Nonharmonic oscillations of nanosized cantilevers due to quantum-size effects
Maurin et al. An application of the catastrophe theory to building the model of elastic-plastic behaviour of materials. An application of the catastrophe theory to building the model of elastic-plastic behaviour of materials. Part 1. Uniaxial deformation (stress)
SU962522A1 (en) Reinforcement member
SU179799A1 (en) REJECTABLE VOLUME RESONATOR
Preidikman et al. Forced oscillations of microelectromechanical resonators
Eid Stability of asymmetric quantum-corrected thin-shell wormholes
Kononenko Numerical analysis of the eigen modes for the modern gyrotron resonators
Jarvis et al. Structural evolution under pressure in single-crystal layered antiferromagnets MPS 3 (M= Fe, Ni, Mn)

Legal Events

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

Ref document number: 09745113

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 09745113

Country of ref document: EP

Kind code of ref document: A1