EP0021523A1 - Bandsperrfilter für eine Mikrowellenübertragungsleitung und Polarisationsschaltung eines Mikrowellentransistors mit diesem Filter - Google Patents
Bandsperrfilter für eine Mikrowellenübertragungsleitung und Polarisationsschaltung eines Mikrowellentransistors mit diesem Filter Download PDFInfo
- Publication number
- EP0021523A1 EP0021523A1 EP19800200567 EP80200567A EP0021523A1 EP 0021523 A1 EP0021523 A1 EP 0021523A1 EP 19800200567 EP19800200567 EP 19800200567 EP 80200567 A EP80200567 A EP 80200567A EP 0021523 A1 EP0021523 A1 EP 0021523A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- filter
- transmission
- frequency
- notch filter
- equal
- 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.)
- Granted
Links
- 230000005540 biological transmission Effects 0.000 title claims abstract description 55
- 238000000034 method Methods 0.000 claims abstract description 3
- 230000010287 polarization Effects 0.000 claims description 2
- 238000001914 filtration Methods 0.000 abstract description 14
- 235000021183 entrée Nutrition 0.000 description 3
- 241001080024 Telles Species 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
- H01P1/201—Filters for transverse electromagnetic waves
- H01P1/203—Strip line filters
- H01P1/2039—Galvanic coupling between Input/Output
Definitions
- the present invention relates to a notch filter for microwave transmission line with distributed constants produced in planar structure and in particular according to the microstrip technique, as well as a microwave transistor bias circuit comprising this filter.
- a conventional way of ensuring the reception of a microwave signal consists in providing in the receiver a mixer which receives on the one hand this useful microwave signal of frequency f S and on the other hand a signal of frequency f OL delivered by an oscillator local and which delivers a signal at an intermediate frequency f FI equal to the difference of the frequencies f S and f OL .
- a filter must be placed which prevents the transmission of the frequencies f S and f OL while promoting that of the lower frequency f FI ', that is to say a low-pass filter or at less tape cutter.
- the object of the invention is to propose a band-cut microwave filter which avoids such necessarily unsatisfactory compromises and which proves to be extremely compact while presenting a fairly wide cut band and offering a short-circuit plane well located by compared to the mixer to optimize the yield thereof.
- the notch filter thus produced uses an extremely small space very effectively, since the combination of the two filtering elements and a judicious choice of their dimensions make it possible to obtain at will the desired width of cut band.
- the filter may comprise at least a third filtering element intended to prevent the transmission of a third frequency band of the dual frequency centered on the central frequency of the second frequency band and composed of a quarter electrical wavelength filter ⁇ 2/8 placed in parallel on one of the two transmission paths at a distance from the entry point of the notch filter equal to (n - 1) ⁇ 1/2 , n being a positive integer compatible with the length of the transmission paths , or alternatively, intended to prevent the transmission of a third frequency band centered on the frequency twice the central frequency of the first frequency band and composed of a quarter wave filter of electrical length ⁇ 1 / 8 placed in parallel on one of the
- the notch filter shown in FIG. 1 has an entry point E, to which an upstream part L of the transmission line is connected, to which the filter is incorporated, and an exit point S, to which a downstream part is connected L of this transmission line.
- This notch filter is composed, according to the invention, of a first filter element 20 and of a second filter element 10, intended to prevent the transmission respectively of a first frequency band and of a second frequency band adjacent to the first.
- Element 10 is composed of a quarter-wave filter, of electrical length equal to a quarter of the wavelength ⁇ 2 associated with the center frequency of the second frequency band, and placed at the entry point E of the notch filter.
- the element 20 is composed of a set of two transmission paths 21 and 22 in parallel which separate at the entry point E, in the short-circuit plane defined by the presence of the second filter element 10, surround this element 10 and regroup at the exit point S.
- the first channel 21 follows in the example here describes a path in an arc of a circular length ⁇ 1/4 ( ⁇ 1 being the wavelength associated with the central frequency of the first frequency band), while the second channel 22 follows a path in a complementary arc, of electrical length 3 ⁇ 1/4 .
- the signals at the frequency corresponding to the wavelength ⁇ 1 therefore arrive in phase opposition and no signal at this frequency is transmitted to part L of the line of transmission.
- the outline of the notch filter is obviously extremely compact, since the circular shape adopted for element 20 is very compact and the interior of this first element is used for positioning. of the second filter element. Furthermore, the insulation provided by the notch filter according to the invention is excellent, and limited only by the parasitic coupling (higher modes) which can appear between E and S (an attenuation of 60 dB can for example be obtained if you don't want a bandwidth greater than a few percent).
- the electrical lengths of the two transmission channels can be greater than those of the example described above; it is only important that each of these lengths is equal to an odd number of times a quarter of the wavelength ⁇ 1 and that the difference between these lengths is equal to (2m -1) ⁇ 1/2 so that the opposition phase is well obtained in S (m is any positive integer).
- the example described above, which corresponds to m 1, however corresponds to the most compact and therefore the most advantageous embodiment, in two respects moreover, on the one hand for its use in applications where the small footprint components play a key role, and on the other hand to better focus the electric fields and magnetic and thus make the filter less sensitive to proximity effects.
- the wavelength ⁇ 2 is for example that associated with the useful microwave signal of frequency f s received and intended for the mixer (for example a microwave diode), and the length d wave ⁇ 1 that which is associated with the frequency signal f OL supplied by the local oscillator and also sent to the mixer.
- the downstream part L of the transmission line receives only the frequency signal f FI supplied by the non-linear component that constitutes the mixer; the fre- q uence f S and f OL signals do not reach this part L s, thanks to the combined action of the filter elements 20 and 10.
- this filter comprises, in accordance with FIG. 2a, a third filtering element 30, intended to prevent the transmission of a third frequency band centered on the frequency twice the center frequency of the first frequency band.
- the signal of frequency f OL delivered by the local oscillator has an amplitude in general much higher than that of the microwave signal received, of frequency f S , and the presence of l harmonic of rank 2 of this frequency signal f OL therefore corresponds to a significant loss of energy.
- the introduction of the third filter element 30 makes it possible to prevent the transmission of this harmonic and to avoid the deterioration of the efficiency which results from such a transmission.
- this third filtering element can be provided, if necessary, for transmitting the transmission of a third frequency band-centered on the harmonic of rank 2 of the center frequency of the second frequency band, and no longer of the first frequency band.
- the third filter element 30 is a quarter-wave filter placed in parallel on the second transmission channel 22, at a distance from the entry point E of the notch filter equal to ⁇ 1/2 (or, if the lengths of the transmission paths are higher than those of the embodiments shown in the figures, n ⁇ 2/2, n being a positive integer compatible with the respective lengths.
- the length of this filter is ⁇ 1/8 if we want to eliminate the harmonic of rank 2 from the signal filtered by the first wire element tration 20 or ⁇ 2/8 if it is desired to eliminate the second harmonic 2 of the signal filtered by the second filter element 10.
- Figure 2b shows an alternative embodiment in which this element 30 is directed inward of the ring.
- This variant is very advantageous since it retains the notch filter according to the invention its extremely compact character, despite the presence of an additional filter element.
- FIG. 3 shows another possible application of the invention, namely the incorporation of the notch filter into the bias circuit of a microwave transistor.
- the notch filter according to the invention is connected (perpendicularly in the present case), at its entry point E, to a section 40 of transmission line, itself placed in parallel on a transmission line 41 comprising a microwave transistor 42 and a capacitor 45.
- the length of the section 40 is equal to a quarter of the wavelength associated with the microwave signal crossing the transmission line 41.
- the filter is also connected (perpendicularly), at its output point S , to a supply circuit 43 of the transistor 42.
- This arrangement allows the circuit 43 to ensure the bias of the transistor 42 by transmission of its bias voltage through the line section 44, the notch filter (such as that in FIG. 1 for example), the section 40 and the line 41. Conversely, the microwave signal which traverses the line 41 cannot reach the circuit 43 because of the effective barrier constituted by the notch filter. The filtering action is even more effective if the section 40 is given as high an impedance as possible.
- the present invention is not limited to the few exemplary embodiments which have just been described and shown, from which other alternative embodiments can be provided without thereby departing from the scope of the invention.
- the circular arrangement of the two transmission channels of the first filter element has been recognized as being as compact as possible, but a square or rectangle arrangement, for example, remains very compact and therefore almost as advantageous as that described and shown. .
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
- Waveguide Connection Structure (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7916260 | 1979-06-25 | ||
FR7916260A FR2460049A1 (fr) | 1979-06-25 | 1979-06-25 | Filtre coupe-bande pour ligne de transmission hyperfrequence et circuit de polarisation de transistor hyperfrequence comprenant ce filtre |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0021523A1 true EP0021523A1 (de) | 1981-01-07 |
EP0021523B1 EP0021523B1 (de) | 1986-05-07 |
Family
ID=9227049
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19800200567 Expired EP0021523B1 (de) | 1979-06-25 | 1980-06-17 | Bandsperrfilter für eine Mikrowellenübertragungsleitung und Polarisationsschaltung eines Mikrowellentransistors mit diesem Filter |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0021523B1 (de) |
JP (1) | JPS566501A (de) |
AU (1) | AU536334B2 (de) |
BR (1) | BR8003890A (de) |
CA (1) | CA1159118A (de) |
DE (1) | DE3071590D1 (de) |
FR (1) | FR2460049A1 (de) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0731521A1 (de) * | 1992-04-30 | 1996-09-11 | Matsushita Electric Industrial Co., Ltd. | Schleifenförmiger Zweifachmodus-Streifenresonator um Mikrowellen in zwei Moden zu resoneren und Bandpassfilter mit den Resonatoren |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2510326A1 (fr) * | 1981-07-24 | 1983-01-28 | Thomson Csf | Filtre passe-bande a resonateurs lineaires ouverts a leurs deux extremites |
FR2517491A1 (fr) * | 1981-11-27 | 1983-06-03 | Labo Electronique Physique | Combineur-melangeur a transistor double source |
JP5749133B2 (ja) * | 2011-10-04 | 2015-07-15 | 古河電気工業株式会社 | 高周波モジュール |
JP7133486B2 (ja) * | 2019-01-16 | 2022-09-08 | 日立Astemo株式会社 | 信号伝送装置、信号伝送システム |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2874276A (en) * | 1952-05-08 | 1959-02-17 | Int Standard Electric Corp | Unitary antenna-receiver utilizing microstrip conductors |
FR72524E (fr) * | 1951-05-23 | 1960-04-14 | Int Standard Electric Corp | Système de transmission pour haute fréquence |
US3150325A (en) * | 1962-04-12 | 1964-09-22 | Donald J Blattner | Wide band traveling wave parametric amplifier |
DE2453605A1 (de) * | 1974-11-12 | 1976-05-13 | Siemens Ag | Einrichtung zur zusammenschaltung von signalenergie |
DE2804118A1 (de) * | 1978-01-31 | 1979-08-02 | Siemens Ag | Mikrowellen-ringhybridschaltung in streifenleitungstechnik |
US4185252A (en) * | 1978-05-10 | 1980-01-22 | The United States Of America As Represented By The Secretary Of The Army | Microstrip open ring resonator oscillators |
EP0015610A1 (de) * | 1979-03-06 | 1980-09-17 | Laboratoires D'electronique Et De Physique Appliquee L.E.P. | Spiegelfrequenzreflektierendes Mikrowellenfilter und Mikrowellenempfänger mit einem solchen Filter |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5352336A (en) * | 1976-10-22 | 1978-05-12 | Mitsubishi Electric Corp | Dividing filter |
-
1979
- 1979-06-25 FR FR7916260A patent/FR2460049A1/fr active Granted
-
1980
- 1980-06-17 EP EP19800200567 patent/EP0021523B1/de not_active Expired
- 1980-06-17 DE DE8080200567T patent/DE3071590D1/de not_active Expired
- 1980-06-18 CA CA000354236A patent/CA1159118A/en not_active Expired
- 1980-06-23 JP JP8504780A patent/JPS566501A/ja active Granted
- 1980-06-23 AU AU59514/80A patent/AU536334B2/en not_active Ceased
- 1980-06-23 BR BR8003890A patent/BR8003890A/pt not_active IP Right Cessation
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR72524E (fr) * | 1951-05-23 | 1960-04-14 | Int Standard Electric Corp | Système de transmission pour haute fréquence |
US2874276A (en) * | 1952-05-08 | 1959-02-17 | Int Standard Electric Corp | Unitary antenna-receiver utilizing microstrip conductors |
US3150325A (en) * | 1962-04-12 | 1964-09-22 | Donald J Blattner | Wide band traveling wave parametric amplifier |
DE2453605A1 (de) * | 1974-11-12 | 1976-05-13 | Siemens Ag | Einrichtung zur zusammenschaltung von signalenergie |
DE2804118A1 (de) * | 1978-01-31 | 1979-08-02 | Siemens Ag | Mikrowellen-ringhybridschaltung in streifenleitungstechnik |
US4185252A (en) * | 1978-05-10 | 1980-01-22 | The United States Of America As Represented By The Secretary Of The Army | Microstrip open ring resonator oscillators |
EP0015610A1 (de) * | 1979-03-06 | 1980-09-17 | Laboratoires D'electronique Et De Physique Appliquee L.E.P. | Spiegelfrequenzreflektierendes Mikrowellenfilter und Mikrowellenempfänger mit einem solchen Filter |
Non-Patent Citations (3)
Title |
---|
ELECTRONICS LETTERS, Vol. 14, No. 16, 3 Aout 1978 Hitchin Herts GB G. D'INZEO et al.: "Microwave planar networks: the annular structure", pages 526-528 * En entier * * |
JOURNAL OF THE ASIA ELECTRONICS UNION, Vol. 3, No. 3, 1970 Tokyo JP K.K. PANG et al.: "Design of a stripline filter using high-Q triplate lines", pages 38-39 * En entier * * |
L'ONDE ELECTRIQUE, Vol. 53, No. 11 Decembre 1973 Paris FR J. CHRAMIEC et al.: "Etude d'un amplificateur parametrique equilibre", pages 405-411 * En entier * * |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0731521A1 (de) * | 1992-04-30 | 1996-09-11 | Matsushita Electric Industrial Co., Ltd. | Schleifenförmiger Zweifachmodus-Streifenresonator um Mikrowellen in zwei Moden zu resoneren und Bandpassfilter mit den Resonatoren |
US5623238A (en) * | 1992-04-30 | 1997-04-22 | Matsushita Electric Industrial Co., Ltd. | Strip line filter having dual mode loop resonators |
US5703546A (en) * | 1992-04-30 | 1997-12-30 | Matsushita Electric Industrial Co., Ltd. | Strip line filter having dual mode loop resonators |
Also Published As
Publication number | Publication date |
---|---|
EP0021523B1 (de) | 1986-05-07 |
AU536334B2 (en) | 1984-05-03 |
FR2460049A1 (fr) | 1981-01-16 |
DE3071590D1 (en) | 1986-06-12 |
FR2460049B1 (de) | 1983-07-08 |
JPS6322481B2 (de) | 1988-05-12 |
BR8003890A (pt) | 1981-01-13 |
AU5951480A (en) | 1981-01-08 |
JPS566501A (en) | 1981-01-23 |
CA1159118A (en) | 1983-12-20 |
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