CN113131110A

CN113131110A - W-band E-plane waveguide filter

Info

Publication number: CN113131110A
Application number: CN202110415147.7A
Authority: CN
Inventors: 江云; 吴微微; 黄昭宇; 叶源; 袁文韬; 黄敬健; 王青平; 袁乃昌
Original assignee: National University of Defense Technology
Current assignee: National University of Defense Technology
Priority date: 2021-04-17
Filing date: 2021-04-17
Publication date: 2021-07-16
Anticipated expiration: 2041-04-17
Also published as: CN113131110B

Abstract

The invention relates to the field of filters, in particular to a W-band E-plane waveguide filter, which comprises a lower cavity and an upper cavity, wherein the upper part of the lower cavity is connected with the lower part of the upper cavity, the upper surface of the lower cavity is provided with a groove, a dielectric substrate is arranged in the groove, the dielectric substrate sequentially comprises a lower grounding layer, a dielectric layer and a metal foil layer from bottom to top, and the metal foil layer is provided with a miniaturized linear type multimode resonator, an upper grounding layer and a lower grounding layer. The invention has the advantages that the dielectric substrate provided with the miniaturized linear type multimode resonator is arranged in the lower cavity and the upper cavity, so that the volume of the W-band E-plane waveguide filter can be reduced. The invention has simple and compact structure, low processing difficulty, flexible and controllable center frequency and bandwidth, excellent performance, good design freedom and rectangular coefficient, can achieve the design purpose by reasonably adjusting the size of each parameter according to the requirements of different applications, and can be widely applied to various fields of W-band radar systems.

Description

W-band E-plane waveguide filter

Technical Field

The invention relates to the field of filters, in particular to a W-band E-plane waveguide filter.

Background

With the wide application and development of wireless communication and satellite communication in recent decades, the available spectrum resources are increasingly strained, and wireless communication technology is also developed from traditional microwave communication to millimeter wave communication in higher frequency bands. Generally, the millimeter waves studied mainly include electromagnetic waves with wavelengths of 3mm, 6mm and 8mm, wherein the electromagnetic waves with wavelengths of 3mm and 8mm correspond to the W band and Ka band in the microwave frequency domain division, respectively; meanwhile, the electromagnetic waves in the W band and the Ka band are called as atmospheric windows because the attenuation in the atmosphere is small. The W-band electromagnetic wave as one of the atmospheric windows is widely applied to systems such as radar and guidance, electronic countermeasure, array imaging, medical detection, automobile collision avoidance and the like due to the short wavelength, wide frequency band and abundant spectrum resources. The millimeter wave filter is a device for separating millimeter wave signals with different frequencies, and the millimeter wave filter is mainly used for suppressing unnecessary signal frequencies and enabling the necessary signal frequencies to pass smoothly. The metal waveguide filter has the advantages of small conductor loss and medium (the medium in the cavity is generally air) loss, large power capacity, no radiation loss and the like, and is widely applied to various fields of millimeter wave communication, radars, guidance, remote sensing, satellite communication, wireless communication, military electronic countermeasure and the like. However, the conventional W-band waveguide filter is designed by using a metal cavity; meanwhile, in order to improve the selection characteristic of the waveguide filter, a designer designs the waveguide filter by adopting cross coupling between the cavities. Although the cross coupling technology between the cavities improves the selectivity of the waveguide filter, the volume of the waveguide filter is increased along with the increase of the additional cavities, and the processing difficulty and the processing cost are increased.

In order to overcome the defects of large volume and heavy weight of the traditional waveguide filter, in 1974, Konishi firstly proposed a new waveguide filter implementation structure, namely an E-plane waveguide filter, wherein a metal sheet containing a plurality of inductive metal strips is inserted into a waveguide symmetric plane (E plane), and the width and the interval of each metal strip on the metal sheet are obtained through theoretical analysis. The E-plane waveguide filter has been widely used due to its superior performance of low loss, high Q value, low cost, convenient processing and suitability for mass production. However, the conventional W-band E-plane waveguide filter is designed by using a plurality of resonant cells or a plurality of resonant cavities, which not only increases the complexity of the filter design, but also increases the size and loss thereof. With the rapid development of the emerging W-band radar system, the wave filter also provides more and more challenges and more rigorous requirements on the factors such as the performance, the size, the cost and the like of the W-band waveguide filter, and the traditional E-surface metal diaphragm waveguide filter cannot completely meet the application requirements of the modern radar system.

Disclosure of Invention

The technical problem to be solved by the invention is that the existing filter has the defects of large volume, complex structure, poor controllability of bandwidth and center frequency, large processing difficulty and poor selectivity.

The invention relates to a W-band E-plane waveguide filter, which comprises a lower cavity and an upper cavity, wherein the upper part of the lower cavity is connected with the lower part of the upper cavity, the upper surface of the lower cavity is provided with a groove, a dielectric substrate is arranged in the groove, the upper part of the dielectric substrate is provided with a metal foil layer, the lower part of the dielectric substrate is provided with a lower grounding layer, the metal foil layer is provided with an upper grounding layer and a miniaturized linear type multimode resonator, the lower grounding layer and the upper grounding layer are connected through the upper cavity and the lower cavity, and the miniaturized linear type multimode resonator is respectively symmetrical along the transverse direction and the longitudinal direction relative to the.

Furthermore, the miniaturized linear multi-mode resonator is provided with five transverse rectangular metal foil strips and three longitudinal rectangular metal foil strips, the five transverse rectangular metal foil strips are respectively a first transverse rectangular metal foil strip, a second transverse rectangular metal foil strip, a third transverse rectangular metal foil strip, a fourth transverse rectangular metal foil strip and a fifth transverse rectangular metal foil strip, the three longitudinal rectangular metal foil strips are respectively a first longitudinal rectangular metal foil strip, a second longitudinal rectangular metal foil strip and a third longitudinal rectangular metal foil strip, the first longitudinal rectangular metal foil strip and the third longitudinal rectangular metal foil strip are respectively connected with two ends of the second transverse rectangular metal foil strip, the second longitudinal rectangular metal foil strip is respectively connected with the first transverse rectangular metal foil strip, the second transverse rectangular metal foil strip, the third transverse rectangular metal foil strip, the fourth transverse rectangular metal foil strip and the fifth transverse rectangular metal foil strip, the first transverse rectangular metal foil strip and the fifth transverse rectangular metal foil strip are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip, the second transverse rectangular metal foil strip and the fourth transverse rectangular metal foil strip are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip, and the first longitudinal rectangular metal foil strip and the third longitudinal rectangular metal foil strip are transversely symmetrical with respect to the second longitudinal rectangular metal foil strip.

Further, the upper ground layer has a first upper ground layer and a second upper ground layer in a lateral direction, and the first upper ground layer and the second upper ground layer are disposed on both sides of the miniaturized linear multimode resonator, and are symmetrical in the lateral direction with respect to the center of the miniaturized linear multimode resonator.

Further, the miniaturized line type multimode resonator is designed between the first upper ground layer and the second upper ground layer to be symmetrical in the lateral direction and the longitudinal direction with respect to the centers of the first upper ground layer and the second upper ground layer, respectively.

Furthermore, the lower grounding layer is provided with a first lower grounding layer and a second lower grounding layer which are transverse, and the first lower grounding layer and the second lower grounding layer are respectively positioned at two sides in the groove.

Further, the groove has a first groove and a second groove.

Furthermore, a lower air cavity is formed in the upper surface of the lower cavity, an upper air cavity is correspondingly formed in the lower surface of the upper cavity, and the lower air cavity is communicated with the groove.

Furthermore, a plurality of connecting holes are respectively formed in the lower cavity and the upper cavity, and connecting pieces are correspondingly arranged in the connecting holes.

Furthermore, a first pin hole, a second pin hole and a first hollow hole are respectively formed in the lower cavity, and a third pin hole, a fourth pin hole and a second hollow hole are respectively formed in the upper cavity.

Furthermore, the dielectric substrate is inserted into a groove formed in the lower cavity and forms a W-band E-plane waveguide filter together with the upper cavity. The center of the W-band E-plane waveguide filter structure is an origin, the short side of the dielectric substrate is an x-axis, the long side of the dielectric substrate is a y-axis, a z-axis is determined according to a right-hand rule, the W-band E-plane waveguide filter structure is symmetrical about the y-axis, the dielectric substrate is symmetrical left and right about the x-axis and symmetrical up and down about the y-axis, and the miniaturized linear multi-mode resonator is symmetrical left and right about the x-axis and symmetrical up and down about the y-axis.

The invention has the advantages that the dielectric substrate provided with the first resonance unit is arranged in the lower cavity and the upper cavity, so that the volume of the W-band E-plane waveguide filter can be reduced, the design complexity of the W-band E-plane waveguide filter is reduced, and the design flexibility of the W-band E-plane waveguide filter is improved. The invention has simple and compact structure, low processing difficulty, flexible and controllable center frequency and bandwidth, excellent performance, good design freedom and rectangular coefficient, can achieve the design purpose by reasonably adjusting the size of each parameter according to the requirements of different applications, and can be widely applied to various fields of W-band radar systems.

Drawings

FIG. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a schematic view of a metal foil layer structure of the present invention;

FIG. 3 is a schematic view of a lower sub-layer configuration of the present invention;

FIG. 4 is a schematic view of the lower chamber structure of the present invention;

FIG. 5 is a schematic view of the upper chamber structure of the present invention;

FIG. 6 is a schematic structural view of the upper and lower chambers of the present invention after combination;

FIG. 7 is a simulation model of a W-band E-plane waveguide filter in an electromagnetic simulation software HFSS according to the present invention;

fig. 8 is a schematic diagram of the variation of the transmission coefficient (S21) of the W-band E-plane waveguide filter with Frequency (Frequency) in the electromagnetic simulation software HFSS when the third transverse rectangular metal foil strip is in different lengths according to the present invention;

fig. 9 is a schematic diagram of the transmission coefficients (S21) of the W-band E-plane waveguide filter in the electromagnetic simulation software HFSS varying with Frequency (Frequency) when the first transverse rectangular metal foil strip and the fifth transverse rectangular metal foil strip have different lengths according to the present invention;

fig. 10 is a schematic diagram of the transmission coefficients (S21) of the W-band E-plane waveguide filter in the electromagnetic simulation software HFSS varying with Frequency (Frequency) when the second transverse rectangular metal foil strip and the fourth transverse rectangular metal foil strip have different lengths according to the present invention;

FIG. 11 is the final simulation result of the invention using HFSS electromagnetic simulation software.

In the figure, 1, a metal foil layer 2, a dielectric substrate 3, a lower ground layer 31, a first lower ground layer 32, a second lower ground layer 4, a lower cavity 41, a screw hole 42, a screw hole 43, a screw hole 44, a screw hole 45, a first groove 46, a second groove 47, a pin hole 48, a pin hole 49, a lower air cavity 410, a first void 411, a first pin hole 412, a second pin hole 5, an upper cavity 51, a screw hole 52, a screw hole 53, a screw hole 54, a screw hole 55, a pin hole 56, a pin hole 57, a lower air cavity 58, a second void 59, a third pin hole 510, a fourth pin hole 6, a miniaturized linear multi-mode resonator 61, a first transverse rectangular metal foil strip 62, a second transverse rectangular metal foil strip 63, a third transverse rectangular metal foil strip 64, a fourth transverse rectangular metal foil strip 65, a fifth transverse rectangular metal foil strip 66, a first longitudinal metal foil strip 67, a second longitudinal rectangular metal foil strip 68, a third transverse rectangular metal foil strip 68, a pin hole 6, a pin holes, A third longitudinal rectangular metal foil strip 7, an upper ground layer 71, a first upper ground layer 72 and a second upper ground layer.

Detailed Description

As shown in fig. 1 to 7, a W-band E-plane waveguide filter includes a lower cavity 4 and an upper cavity 5, an upper portion of the lower cavity 4 is connected to a lower portion of the upper cavity 5, a groove is formed in an upper surface of the lower cavity 4, a dielectric substrate 2 is disposed in the groove, a lower ground layer 3 is disposed on a lower portion of the dielectric substrate 2, a metal foil layer 1 is disposed on an upper portion of the dielectric substrate 2, the metal foil layer 1 includes a miniaturized linear multimode resonator 6 and an upper ground layer 7, the lower ground layer 3 and the upper ground layer 7 are connected through the upper cavity 5 and the lower cavity 4, and the miniaturized linear multimode resonator 6 is symmetrical with respect to a center of the upper ground layer 7 in a lateral direction and a longitudinal direction. The dielectric substrate 2 may be a Rogers5880 substrate having a thickness of 0.127 mm. The medium substrate 2 is inserted into a groove formed in the lower cavity 4 and forms a W-band E-plane waveguide filter together with the upper cavity 5. The center of the W-band E-plane waveguide filter structure is an origin, the short side of the dielectric substrate 2 is an x-axis, the long side of the dielectric substrate 2 is a y-axis, a z-axis is determined according to a right-hand rule, the W-band E-plane waveguide filter structure is symmetrical about the y-axis, the dielectric substrate 2 is symmetrical left and right about the x-axis and symmetrical up and down about the y-axis, and the miniaturized linear multi-mode resonator 6 is symmetrical left and right about the x-axis and symmetrical up and down about the y-axis. The dielectric substrate 2 provided with the miniaturized linear type multimode resonator 6 is arranged in the lower cavity 4 and the upper cavity 5, so that the size of the W-band E-surface waveguide filter can be reduced, the design complexity of the W-band E-surface waveguide filter is reduced, and the design flexibility of the W-band E-surface waveguide filter is improved. The small linear type multi-mode resonator has the advantages of simple and compact structure, low processing difficulty, flexible and controllable center frequency and bandwidth, excellent performance, good design freedom and rectangular coefficient, and can achieve the design purpose by reasonably adjusting the parameter size of the small linear type multi-mode resonator according to different application requirements, and can be widely applied to various fields of W-band radar systems. The lower cavity 4 and the upper cavity 5 can be made of copper, and the surfaces of the lower cavity and the upper cavity are plated with gold.

The miniaturized linear type multi-mode resonator 6 is provided with five transverse rectangular metal foil strips and three longitudinal rectangular metal foil strips, wherein the five transverse rectangular metal foil strips are respectively a first transverse rectangular metal foil strip 61, a second transverse rectangular metal foil strip 62, a third transverse rectangular metal foil strip 63, a fourth transverse rectangular metal foil strip 64 and a fifth transverse rectangular metal foil strip 65, the three longitudinal rectangular metal foil strips are respectively a first longitudinal rectangular metal foil strip 66, a second longitudinal rectangular metal foil strip 67 and a third longitudinal rectangular metal foil strip 68, the first longitudinal rectangular metal foil strip 66 and the third longitudinal rectangular metal foil strip 68 are respectively connected with two ends of the second transverse rectangular metal foil strip 63, the second longitudinal rectangular metal foil strip 67 is connected to the first transverse rectangular metal foil strip 61, the second transverse rectangular metal foil strip 62, the third transverse rectangular metal foil strip 63, the fourth transverse rectangular metal foil strip 64 and the fifth transverse rectangular metal foil strip 65, respectively. The first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip 63, the second transverse rectangular metal foil strip 62 and the fourth transverse rectangular metal foil strip 64 are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip 63, and the first longitudinal rectangular metal foil strip 66 and the third longitudinal rectangular metal foil strip 68 are transversely symmetrical with respect to the second longitudinal rectangular metal foil strip 67; the miniaturized linear multimode resonator 6 is symmetrical in the lateral and longitudinal directions with respect to the center of the upper ground layer 7, respectively, the miniaturized linear multimode resonator 6 is printed on a Rogers5880 substrate having a thickness of 0.127mm, and the miniaturized linear multimode resonator 6 has a thickness of 0.017 mm. The third transverse rectangular metal foil strip 63 is 1.45mm long and 0.1mm wide. In the invention, when the transverse rectangular metal foil strips 63 are different in length, the transmission coefficient (S21) of the W-band E-plane waveguide filter is changed along with the Frequency (Frequency) in the electromagnetic simulation software HFSS as shown in FIG. 8; from the simulation results, it can be seen that the W-band E-plane waveguide filter generates a transmission zero at each of the upper and lower stop bands, and the resonant frequency of the transmission zero at the lower stop band can be changed by changing the length of the third transverse rectangular metal foil strip 63 in the linear miniaturized multimode resonator 6, and the resonant frequency of the transmission zero at the upper stop band remains substantially unchanged; the length of the third transverse rectangular metal foil strip 63 is reduced, the resonance frequency of the transmission zero of the lower stop band moves to low frequency, namely the bandwidth of the W-band E-plane waveguide filter is widened; it can be seen that the bandwidth of the W-band E-plane waveguide filter of the present invention can be flexibly controlled by changing the length of the third transverse rectangular metal foil strip 63 of the miniaturized linear multi-mode resonator 6. The first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 are 0.98mm long and 0.1mm wide. When the first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 are in different lengths, the transmission coefficient (S21) of the W-band E-plane waveguide filter changes with Frequency (Frequency) in the electromagnetic simulation software HFSS as shown in FIG. 9; as can be seen from the simulation results, changing the lengths of the first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 in the linear miniaturized multi-mode resonator 6 can change the resonant frequency of the upper stop band transmission zero of the W-band E-plane waveguide filter, and the resonant frequency of the lower stop band transmission zero remains substantially unchanged; the lengths of the first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 are increased, and the resonant frequency of the transmission zero of the upper stop band moves to low frequency, namely the bandwidth of the W-band E-plane waveguide filter is narrowed; therefore, the bandwidth of the W-band E-plane waveguide filter of the present invention can also be flexibly controlled by changing the lengths of the first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 of the miniaturized linear multi-mode resonator 6. The second 62 and fourth 64 transverse rectangular metal foil strips are 1.2mm long and 0.1mm wide. When the second transverse rectangular metal foil strip 62 and the fourth transverse rectangular metal foil strip 64 have different lengths, the transmission coefficient (S21) of the W-band E-plane waveguide filter changes with the Frequency (Frequency) in the electromagnetic simulation software HFSS as shown in FIG. 10; as can be seen from the simulation results, changing the lengths of the second transverse rectangular metal foil strip 62 and the fourth transverse rectangular metal foil strip 64 in the linear miniaturized multi-mode resonator 6 can change the center frequency of the W-band E-plane waveguide filter; the lengths of the second transverse rectangular metal foil strip 62 and the fourth transverse rectangular metal foil strip 64 are increased, and the center frequency of the W-band E-plane waveguide filter moves to a low frequency; therefore, changing the lengths of the second transverse rectangular metal foil strip 62 and the fourth transverse rectangular metal foil strip 64 in the linear miniaturized multi-mode resonator 6 can flexibly control the center frequency of the W-band E-plane waveguide filter. If the widths of the first transverse rectangular metal foil strip 61, the second transverse rectangular metal foil strip 62, the third transverse rectangular metal foil strip 63, the fourth transverse rectangular metal foil strip 64 and the fifth transverse rectangular metal foil strip 65 are changed, the resonant frequencies of the transmission zeros of the upper stop band and the lower stop band can also be changed; in practice, according to the existing processing precision, the widths of the first transverse rectangular metal foil strip 61, the second transverse rectangular metal foil strip 62, the third transverse rectangular metal foil strip 63, the fourth transverse rectangular metal foil strip 64 and the fifth transverse rectangular metal foil strip 65 are all determined to be 0.1 mm. The first longitudinal rectangular metal foil strip 66 and the third longitudinal rectangular metal foil strip 68 have a length of 1mm and a width of 0.1 mm. The second longitudinal rectangular metal foil strip 67 has a length of 1.02mm and a width of 0.1 mm. The third longitudinal rectangular metal foil strip 68 has a length of 1mm and a width of 0.1 mm. In practical design, if the lengths and widths of the first longitudinal rectangular metal foil strip 66, the second longitudinal rectangular metal foil strip 67 and the third longitudinal rectangular metal foil strip 68 are changed, the resonant frequencies of the transmission zeros of the upper stop band and the lower stop band can also be changed; from simulation results and structures, it is not difficult to find that the miniaturized linear type multimode resonator 6 provided by the invention not only has simple and compact structure and low processing difficulty, but also has flexible and adjustable bandwidth and center frequency, and is very suitable for designing a W-band E-surface waveguide filter with low cost, low weight, excellent performance, simple and compact structure and flexible design.

The upper ground layer 7 is provided with a first upper ground layer 71 and a second upper ground layer 72 which are transverse, the first upper ground layer 71 and the second upper ground layer 72 are arranged on two sides of the miniaturized linear type multi-mode resonator 6 and are symmetrical along the transverse direction relative to the center of the miniaturized linear type multi-mode resonator 6, and therefore the design can not only ensure the compact structure of the W-band E-plane waveguide filter, but also ensure the symmetry along the x axis and the y axis. Printing a first upper grounding layer 71 and a second upper grounding layer 72 on a dielectric substrate 2, wherein the thickness of the dielectric substrate is 0.017mm, and the length of the dielectric substrate is 0.68mm, so that the dielectric substrate 2 can be well contacted with the lower surface of the metal rectangular waveguide upper cavity 5, and the compact structure of the dielectric substrate 2 can be ensured; if the length of the grounding layer 7 on the dielectric substrate 2 along the y axis on the dielectric substrate is too short, the dielectric substrate 2 cannot be ensured to be in good contact with the lower surface of the metal rectangular waveguide upper cavity 5; if the length of the upper metal grounding layer 7 of the dielectric substrate 2 along the y-axis is too long, the volume of the dielectric substrate 2 is increased, and the dielectric substrate 2 may be deformed in the process of extruding the metal rectangular waveguide upper cavity 5 and the metal rectangular waveguide lower cavity 4; the miniaturized linear multi-mode resonator 6 is located between the first upper ground layer 71 and the second upper ground layer 72, and is symmetrical with respect to the center of the upper ground layer 7 in the lateral direction and the longitudinal direction, respectively, and the distance from the miniaturized linear multi-mode resonator 6 to the first upper ground layer 71 and the second upper ground layer 72 is 0.135mm along the x-axis, which can ensure not only the compact structure of the W-band E-plane waveguide filter but also the symmetry of the W-band E-plane waveguide filter along the x-axis. The distance from the miniaturized linear type multimode resonator 6 to the first upper ground layer 71 and the second upper ground layer 72 is 0.785mm along the y-axis, so that the arrangement can ensure that not only the W-band E-plane waveguide filter has good return loss, but also the W-band E-plane waveguide filter is symmetrical along the x-axis.

The lower ground layer 3 has a first lower ground layer 31 and a second lower ground layer 32, which are laterally arranged, and the first lower ground layer 31 and the second lower ground layer 32 are respectively arranged at two sides of the groove. The first lower grounding layer 31 and the second lower grounding layer 32 are printed on the dielectric substrate 2, the thickness is 0.017mm, and the length along the x axis is 0.68mm, so that the dielectric substrate 2 can be well installed in the first groove 45 and the second groove 46 formed in the metal rectangular waveguide lower cavity 4, and meanwhile, the lower grounding layer of the dielectric substrate 2 can be guaranteed to be in good contact with the upper surface of the metal rectangular waveguide lower cavity 4; the first lower ground layer 31 and the second lower ground layer 32 are symmetrical along the x-axis with respect to the center of the dielectric substrate 2, so as to further ensure that the dielectric substrate 2 is in contact with the upper surface of the metal rectangular waveguide lower cavity 4; the combined action of the upper grounding layer 7 of the dielectric substrate and the lower grounding layer 3 of the dielectric substrate can ensure that the ground of the dielectric substrate 2 is in good contact with the cavity ground formed by the lower cavity 4 of the metal rectangular waveguide and the upper cavity 5 of the metal rectangular waveguide, so that the generation of a high-order mode of the W-band E-plane waveguide filter is inhibited.

The grooves have a first groove 45 and a second groove 46. The structure is convenient for placing the dielectric substrate 2 into the groove, and the volume of the W-band E-plane waveguide filter can be further reduced. The first groove 45 and the second groove 46 are communicated with the lower air cavity 49, so that the radio-frequency signals of the W wave band can be ensured to smoothly pass through, and the dielectric substrate 2 is placed in the grooves, so that the structure of the wave filter of the E surface of the W wave band is realized. The width of the first groove 45 and the second groove 46 along the x axis is 0.7mm, the length along the y axis is 3.22mm, and the depth along the z axis is 0.15mm, so that the dielectric substrate 2 can be better installed in the first groove 45 and the second groove 46, and the leakage of the radio frequency signal in the W waveband can be prevented.

The upper surface of the lower cavity 4 is provided with a lower air cavity 49, the lower surface of the upper cavity 5 is correspondingly provided with an upper air cavity 57, and the lower air cavity 49 is communicated with the groove. The lower air cavity 49 and the upper air cavity 57 together form a standard W-band rectangular waveguide resonant cavity, and the input and output ports are standard rectangular waveguide ports WR10(a is 1.27mm, and b is 2.54 mm).

And a plurality of connecting holes are respectively formed in the lower cavity 4 and the upper cavity 5, and connecting pieces are correspondingly arranged in the connecting holes. The connecting holes can be screw holes, pin holes and the like, and the connecting pieces can be screws, pins and the like. In the figures,

reference numerals

41, 42, 43, 44, 51, 52, 53 and 54 are all screw holes, and screws are correspondingly arranged in the screw holes. 47. 48, 55 and 56 are pin holes, and pins are correspondingly arranged in the pin holes. The diameters of the pin holes are all 1.65mm, and the diameters of the screw holes are all 2 mm.

In order to facilitate the connection between the lower cavity 4 and the upper cavity 5 with other devices, the lower cavity 4 is respectively provided with a first pin hole 411, a second pin hole 412 and a first hollow hole 410, and the upper cavity 5 is respectively provided with a third pin hole 59, a fourth pin hole 510 and a second hollow hole 58. The diameters of the pin holes are all 1.65mm, and the diameters of the empty holes are all 3 mm.

The upper grounding layer 7 and the lower grounding layer 3 are connected through the lower surface of the upper cavity 4 and the upper surface of the lower cavity 5, when the upper cavity 4 and the lower cavity 5 are fixed through screws, good connection of the upper grounding layer and the lower grounding layer can be guaranteed, and meanwhile good contact between the upper grounding layer 7 and the lower grounding layer 3 and the cavity ground can also be guaranteed.

The lower air cavity 49 and the upper air cavity 57 are both 1.27mm deep along the x-axis, 13mm long along the y-axis, and 1.27mm deep along the z-axis.

The diameters of the pin holes are all 1.65mm, the diameters of the screw holes are all 2mm, and the diameters of the empty holes are all 3 mm.

The dielectric substrate 2 has a length of 2.67mm along the x-axis and 3.21mm along the y-axis.

The first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 of the miniaturized linear multi-mode resonator are 0.98mm in length along the x axis, 0.1mm in width along the y axis and 0.017mm in thickness along the z axis; the distance between the first transverse rectangular metal foil strip 61 and the fifth transverse rectangular metal foil strip 65 and the third transverse rectangular metal foil strip 63 along the x axis is 0.3 mm; the second 62 and fourth 64 transverse rectangular metal foil strips are 1.2mm long along the x-axis, 0.1mm wide along the y-axis, and 0.017mm thick along the z-axis; the distance between the second transverse rectangular metal foil strip 62, the fourth transverse rectangular metal foil strip 64 and the third transverse rectangular metal foil strip 63 along the x axis is 0.1 mm; the third transverse rectangular metal foil strip 63 has a length of 1.45mm along the x-axis, a width of 0.1mm along the y-axis, and a thickness of 0.017mm along the z-axis; the first longitudinal rectangular metal foil strip 66 and the third longitudinal rectangular metal foil strip 68 are 1mm in length, 0.1mm in width and 0.017mm in thickness along the z-axis; the length of the second longitudinal rectangular metal foil strip b (67) is 1.02mm, the width of the second longitudinal rectangular metal foil strip b is 0.1mm, and the thickness of the second longitudinal rectangular metal foil strip b along the z axis is 0.017 mm; the distance of the miniaturized linear multimode resonator 6 from the first upper ground layer a (71) and the second upper ground layer b (72) is 0.135mm along the x-axis and 0.785mm along the y-axis.

The length of the upper cavity 5 and the length of the lower cavity 4 along the x axis are both 19mm, the length of the upper cavity along the y axis are both 13mm, the length of the lower cavity along the z axis are both 9.5mm, and the length of the upper cavity is 13mm so as to ensure that the upper cavity is convenient to process and test in actual processing and testing.

The sizes are determined according to design and machining precision design by combining actual circuit design basis, theoretical analysis and simulation verification, so that the theoretical accuracy of design is guaranteed, and the accuracy and feasibility of actual machining are guaranteed.

The first groove 45 and the second groove 46 are each 0.7mm long along the x-axis, 13mm long along the y-axis, and 0.15mm deep along the z-axis.

The invention has the advantages of excellent structural performance, simple and compact structure, flexible and controllable center frequency and bandwidth and low processing cost. The invention uses a novel miniaturized linear multi-mode resonator in the design of the W-band E-plane waveguide filter structure, so that 2 transmission zeros are generated in the upper stop band of the filter and 1 transmission zero is generated in the lower stop band of the filter, and the W-band E-plane waveguide filter has high out-of-band rejection and rectangular coefficient. The W-band E-plane waveguide filter structure has good design freedom, and can achieve the design purpose by reasonably adjusting the parameters of the miniaturized linear type multimode resonator according to the requirements of different applications, so that the W-band E-plane waveguide filter structure is easily popularized to the application of millimeter wave radio frequency circuits in various fields.

Claims

A W-band E-plane waveguide filter characterized by: including cavity (4) and last cavity (5) down, the upper portion of cavity (4) and the sub-unit connection of last cavity (5) down, the recess is seted up to the upper surface of cavity (4) down, set up medium base plate (2) in the recess, medium base plate (2) upper portion sets up metal foil layer (1), stratum (3) under medium base plate (2) lower part sets up, metal foil layer (1) has miniaturized multimode linear resonator (6), go up ground plane (7), it connects through last cavity (5) and lower cavity (4) to go up ground plane (3) and last ground plane (7) down, miniaturized linear multimode resonator (6) are along horizontal and longitudinal symmetry respectively about the center of recess.
2. The W-band E-plane waveguide filter of claim 1 wherein: the miniaturized linear type multimode resonator (6) is provided with five transverse rectangular metal foil strips and three longitudinal rectangular metal foil strips, the five transverse rectangular metal foil strips are respectively a first transverse rectangular metal foil strip (61), a second transverse rectangular metal foil strip (62), a third transverse rectangular metal foil strip (63), a fourth transverse rectangular metal foil strip (64) and a fifth transverse rectangular metal foil strip (65), the three longitudinal rectangular metal foil strips are respectively a first longitudinal rectangular metal foil strip (66), a second longitudinal rectangular metal foil strip (67) and a third longitudinal rectangular metal foil strip (68), the first longitudinal rectangular metal foil strip (66) and the third longitudinal rectangular metal foil strip (68) are respectively connected with two ends of the second transverse rectangular metal foil strip (63), and the second longitudinal rectangular metal foil strip (67) is respectively connected with the first transverse rectangular metal foil strip (61), the second transverse rectangular metal foil strip (62), The third transverse rectangular metal foil strip (63), the fourth transverse rectangular metal foil strip (64) and the fifth transverse rectangular metal foil strip (65) are connected, the first transverse rectangular metal foil strip (61) and the fifth transverse rectangular metal foil strip (65) are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip (63), the second transverse rectangular metal foil strip (62) and the fourth transverse rectangular metal foil strip (64) are longitudinally symmetrical with respect to the third transverse rectangular metal foil strip (63), and the first longitudinal rectangular metal foil strip (66) and the third longitudinal rectangular metal foil strip (68) are transversely symmetrical with respect to the second longitudinal rectangular metal foil strip (67).
3. The W-band E-plane waveguide filter of claim 1 wherein: the upper grounding layer (7) is provided with a first upper grounding layer (71) and a second upper grounding layer (72) which are transverse, the first upper grounding layer (71) and the second upper grounding layer (72) are arranged on two sides of the miniaturized linear type multi-mode resonator (6) and are symmetrical along the transverse direction relative to the center of the miniaturized linear type multi-mode resonator (6).
4. The W-band E-plane waveguide filter of claim 1 wherein: the miniaturized linear multimode resonator (6) is designed between the first upper ground layer (71) and the second upper ground layer (72) symmetrically in the lateral direction and the longitudinal direction with respect to the centers of the first upper ground layer (71) and the second upper ground layer (72), respectively.
5. The W-band E-plane waveguide filter of claim 1 wherein: the lower grounding layer (3) is provided with a first transverse lower grounding layer (31) and a second transverse lower grounding layer (32), and the first lower grounding layer (31) and the second lower grounding layer (32) are respectively positioned on two sides in the groove.
6. The W-band E-plane waveguide filter of claim 1 wherein: the groove is provided with a first groove (45) and a second groove (46).
7. The W-band E-plane waveguide filter of claim 1 wherein: the upper surface of the lower cavity (4) is provided with a lower air cavity (49), the lower surface of the upper cavity (5) is correspondingly provided with an upper air cavity (57), and the lower air cavity (49) is communicated with the groove.
8. The W-band E-plane waveguide filter of claim 1 wherein: the lower cavity (4) and the upper cavity (5) are respectively provided with a plurality of connecting holes, and connecting pieces are correspondingly arranged in the connecting holes.
9. The W-band E-plane waveguide filter of claim 1 wherein: the lower cavity (4) is respectively provided with a first pin hole (411), a second pin hole (412) and a first hollow hole (410), and the upper cavity (5) is respectively provided with a third pin hole (59), a fourth pin hole (510) and a second hollow hole (58).
10. The W-band E-plane waveguide filter of any one of claims 1-9 wherein: the dielectric substrate (2) is inserted into a groove formed in the lower cavity (4) and forms a W-band E-plane waveguide filter together with the upper cavity (5); the center of the W-band E-plane waveguide filter structure is an origin, the short side of the dielectric substrate 2 is an x-axis, the long side of the dielectric substrate 2 is a y-axis, a z-axis is determined according to a right-hand rule, the W-band E-plane waveguide filter structure is symmetrical about the y-axis, the dielectric substrate 2 is symmetrical left and right about the x-axis and is symmetrical up and down about the y-axis, and the miniaturized linear multi-mode resonator 6 is symmetrical left and right about the x-axis and is symmetrical up and down about the y-axis.