CN104241741B - A kind of half module substrate integrated wave guide bandpass filter loading L-shaped defect ground structure - Google Patents

Abstract

A half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure, which relates to a half-mode substrate-integrated waveguide bandpass filter, in particular to a half-mode substrate with an L-shaped defect-loaded structure Integrated waveguide bandpass filter. The invention aims to solve the problem that the common substrate integrated waveguide bandpass filter has high operating frequency and narrow relative bandwidth and cannot be applied to mobile communication systems. The invention includes a first metal printing layer, a dielectric substrate, a second metal printing layer and two balanced microstrip lines, the dielectric substrate is a rectangular plate, the first metal printing layer is a rectangular metal sheet, the first metal printing layer, the dielectric substrate , The second metal printing layer is stacked sequentially from top to bottom, the first metal printing layer is printed on the middle of the upper surface of the dielectric substrate, the second metal printing layer is printed on the lower surface of the dielectric substrate, and the two balanced microstrip lines are in the shape of a line Printed on one edge of the upper surface of the dielectric substrate. The invention belongs to the field of wireless communication.

Description

A Half-mode Substrate Integrated Waveguide Bandpass Filter Loaded with L-shaped Defect Ground Structure

technical field

The invention relates to a half-mode substrate integrated waveguide bandpass filter, in particular to a half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure, which belongs to the field of wireless communication.

Background technique

Dielectric integrated waveguide is a waveguide structure that achieves transmission characteristics similar to metal rectangular waveguides on a dielectric substrate. Because of the advantages of low radiation, low insertion loss, miniaturization, and easy integration, this structure has become a research hotspot and is also widely used. and filter design. With the help of printed circuit technology, low-cost mass production of filters based on dielectric integrated waveguides is possible. However, the common substrate-integrated waveguide band-pass filter has a high operating frequency and relatively narrow bandwidth, which restricts its development in mobile communication systems.

Contents of the invention

In order to solve the problem that the ordinary substrate-integrated waveguide band-pass filter has a high operating frequency and a narrow relative bandwidth and cannot be applied to a mobile communication system, the present invention further proposes a half-mode substrate with an L-shaped defect-loaded structure Integrated waveguide bandpass filter.

The technical scheme adopted by the present invention to solve the above problems is: the present invention includes a first metal printing layer, a dielectric substrate, a second metal printing layer and two balanced microstrip lines, the dielectric substrate is a rectangular plate, and the first metal printing layer is Rectangular metal thin plate, the first metal printing layer, the dielectric substrate, and the second metal printing layer are superimposed from top to bottom, the first metal printing layer is printed on the middle of the upper surface of the dielectric substrate, and the second metal printing layer is printed on the middle of the dielectric substrate. On the lower surface, two balanced microstrip lines are printed in a line on one edge of the upper surface of the dielectric substrate, and the two balanced microstrip lines are respectively located at both ends of the first metal printing layer, and one end of each balanced microstrip line is connected to the The edge of one end corresponding to the dielectric substrate is connected, and the other end of each balanced microstrip line is connected to the corresponding end of the first metal printing layer. A row of metallized via holes is opened on one side of the first metal printing layer, and each metal The via holes pass through the first metal printing layer, the dielectric substrate, and the second metal printing layer from top to bottom, and the middle part of one side of the second metal printing layer is provided with a first L-shaped defect structure group, and the first L The group of defect-shaped structures includes three first L-shaped defect structures arranged side by side, and two second L-shaped defect structures are respectively arranged on both sides of the first L-shaped defect structure group, each of the first L-shaped defect structures The vertical end of the defect-shaped structure is in contact with one side edge of the second metal printing layer, and the vertical end of each second L-shaped defect structure is in contact with one side edge of the second metal printing layer.

The beneficial effects of the present invention are: according to the test results of the actual filter, the working frequency band of the filter is 1.75-2.61 GHz, and the relative bandwidth reaches 39.4%. The filter has a printed structure, has the characteristics of low profile, light weight, easy integration and wide bandwidth, and can be widely used in fourth-generation mobile communication systems. The working frequency band of the present invention covers 1.8-2.6 GHz, and the relative bandwidth can reach 36.4%. The filter has a printed structure, has the characteristics of low profile, light weight, easy integration and wide bandwidth, and can be widely used in fourth-generation mobile communication systems.

Description of drawings

Fig. 1 is a front view of the present invention, Fig. 2 is a top view of Fig. 1, Fig. 3 is a bottom view of Fig. 1, and Fig. 4 is a schematic diagram of S parameter test results of the present invention.

detailed description

Specific Embodiment 1: This embodiment is described with reference to FIGS. 1 to 4. A half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure described in this embodiment includes a first metal printing layer 1, a dielectric substrate 2. The second metal printing layer 3 and two balanced microstrip lines 4, the dielectric substrate 2 is a rectangular plate, the first metal printing layer 1 is a rectangular metal sheet, the first metal printing layer 1, the dielectric substrate 2, and the second metal printing layer The printing layers 3 are stacked sequentially from top to bottom, the first metal printing layer 1 is printed on the middle of the upper surface of the dielectric substrate 2, the second metal printing layer 3 is printed on the lower surface of the dielectric substrate 2, and the two balanced microstrip lines 4 are in the form of The inline is printed on one edge of the upper surface of the dielectric substrate 2, and two balanced microstrip lines 4 are respectively located at both ends of the first metal printing layer 1, and one end of each balanced microstrip line 4 corresponds to the dielectric substrate 2 One end edge connection, the other end of each balanced microstrip line 4 is connected to the corresponding end of the first metal printing layer 1, a row of metallized via holes 5 are opened on one side of the first metal printing layer 1, and each metallization The via hole 5 passes through the first metal printing layer 1, the dielectric substrate 2, and the second metal printing layer 3 sequentially from top to bottom, and the middle part of one side of the second metal printing layer 3 is provided with a first L-shaped defect structure group, so The first L-shaped defective structure group includes three first L-shaped defective structures 6 arranged side by side, and two second L-shaped defective structures 7 are respectively arranged on both sides of the first L-shaped defective structure group. , the vertical end of each first L-shaped defective ground structure 6 is in contact with one side edge of the second metal printing layer 3 , and the vertical end of each second L-shaped defective ground structure 7 is in contact with the second metal printing layer 3 Edges touch on one side.

In this embodiment, both ends of the dielectric substrate 2 are respectively connected to a coaxial connector.

Specific Embodiment 2: This embodiment is described in conjunction with FIG. 1 to FIG. 3 . Each balanced microstrip line 4 of a half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure described in this embodiment is composed of the first A rectangular structure section 4-1, a right-angled trapezoidal section 4-2 and a second rectangular structure section 4-3 are sequentially connected from end to end.

The technical effect of this embodiment is: such arrangement can make the feeder line in the form of a gradient line, thereby reducing electromagnetic energy reflection and improving the impedance matching degree. Other components and connections are the same as those in the first embodiment.

Specific embodiment three: This embodiment is described in conjunction with Fig. 1 to Fig. 3 , the first rectangular structure section 4-1 of a half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure described in this embodiment The width is 1.9mm, the width of the second rectangular structure section 4-3 is 5mm, the length of the short base of the right-angled trapezoidal section 4-2 is 1.9mm, and the length of the long base of the right-angled trapezoidal section 4-2 is 5mm. The length of the trapezoidal segment 4-2 is 60 mm.

The technical effect of this embodiment is: such setting can realize better feeder gradual change form and feeder port matching degree. Other components and connections are the same as those in the second embodiment.

Specific Embodiment 4: This embodiment is described in conjunction with Fig. 1 to Fig. 3. The length of the dielectric substrate 2 of the semi-mode substrate integrated waveguide bandpass filter with L-shaped defect-loaded structure described in this embodiment is 270 mm, and the dielectric The width of the substrate 2 is 32.8 mm, the thickness of the dielectric substrate 2 is 0.5 mm, and the dielectric constant of the dielectric substrate 2 is 2.2.

The technical effect of this embodiment is: such setting can make the passband of the filter in the mobile communication frequency band sufficiently wide, and can reduce the dielectric loss. Other components and connections are the same as those in the first embodiment.

Embodiment 5: This embodiment is described with reference to FIGS. 1 to 3. The length of the first metal printing layer 1 of a half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure described in this embodiment is: 120mm, the width of the first metal printing layer 1 is 32.8mm, the thickness of the first metal printing layer 1 is 0.018mm~0.035mm, the length of the second metal printing layer 3 is 270mm, and the width of the second metal printing layer 3 is 32.8mm mm, the thickness of the second metal printing layer 3 is 0.018mm-0.035mm.

The technical effect of this embodiment is: such setting can make the passband of the filter sufficiently wide and reduce the weight of the metal. Other components and connections are the same as those in the first embodiment.

Specific Embodiment Six: This embodiment is described in conjunction with Fig. 1 to Fig. 3. The structure of each first L-shaped defect of a half-mode substrate integrated waveguide bandpass filter loaded with an L-shaped defect structure in this embodiment The length m1 of the vertical groove of 6 is 11.5 mm, the width W1 of the vertical groove of each first L-shaped defective ground structure 6 is 2.4 mm, and the length m2 of the horizontal groove of each first L-shaped defective ground structure 6 is 4mm, the width W2 of the horizontal groove of each first L-shaped defective ground structure 6 is 3mm, the length m3 of the vertical groove of each second L-shaped defective ground structure 7 is 8mm, and each second L-shaped defective ground structure The width W3 of the vertical groove of 7 is 2.4 mm, the length m4 of the horizontal groove of each second L-shaped defective ground structure 7 is 4 mm, and the width W4 of the horizontal groove of each second L-shaped defective ground structure 7 is 2.2 mm .

The technical effect of this embodiment is: with such arrangement, the loaded defective ground structure can be equivalent to the required inductance element within the specified frequency range, and the bandpass filter characteristics can be realized in combination with other parameters. Other components and connections are the same as those in the first embodiment.

Specific Embodiment 7: This embodiment is described with reference to FIGS. 1 to 3. The diameter of each metallized via hole 5 of a half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure described in this embodiment is 1.6 mm, and the center-to-center distance between two adjacent metallized via holes 5 is 2.5 mm.

The technical effect of this embodiment is: such arrangement can effectively shield the electromagnetic energy inside the waveguide and enhance the mechanical strength of the waveguide. Other components and connections are the same as those in the first embodiment.

Embodiment 8: This embodiment is described with reference to FIG. 3 . In this embodiment, two adjacent first L-shaped defect structures 6 of a half-mode substrate integrated waveguide bandpass filter loaded with an L-shaped defect structure The distance J between them is 15 mm, and the distance J between two adjacent second L-shaped defective ground structures 7 is 15 mm. The distance J between them is 15mm.

The technical effect of this embodiment is: with this arrangement, the waveguide between the defect grounds can be equivalent to a capacitive element within a specified frequency range, and the band-pass filter characteristic can be realized in combination with other parameters. Other components and connections are the same as those in the first embodiment.

working principle

The broadband bandpass characteristic of the present invention is mainly realized by loading an L-shaped defect structure on the half-mode substrate integrated waveguide, that is, a special-shaped slot structure. The half-mode substrate integrated waveguide is similar to the traditional dielectric-filled rectangular waveguide and has high-pass characteristics. ; while the L-shaped defect structure has a low-pass characteristic, therefore, the combination of the two will produce a band-pass characteristic.

Claims (7)

1. A semi-mode substrate integrated waveguide bandpass filter with L-shaped defect ground structure, which includes a first metal printing layer (1), a dielectric substrate (2), a second metal printing layer (3) and two The balanced microstrip line (4), the dielectric substrate (2) is a rectangular plate, the first metal printing layer (1) is a rectangular metal sheet, the first metal printing layer (1), the dielectric substrate (2), the second metal printing layer Layers (3) are stacked sequentially from top to bottom, the first metal printing layer (1) is printed on the middle of the upper surface of the dielectric substrate (2), and the second metal printing layer (3) is printed on the lower surface of the dielectric substrate (2) , two balanced microstrip lines (4) are printed on one edge of the upper surface of the dielectric substrate (2) in a straight line, and the two balanced microstrip lines (4) are respectively located at both ends of the first metal printing layer (1) , one end of each balanced microstrip line (4) is connected to the corresponding end edge of the dielectric substrate (2), and the other end of each balanced microstrip line (4) is connected to the corresponding end of the first metal printing layer (1) connection, a row of metallized via holes (5) are opened on one side of the first metal print layer (1), and each metallize via hole (5) passes through the first metal print layer (1), The medium substrate (2), the second metal printing layer (3), the middle part of one side of the second metal printing layer (3) is provided with a first L-shaped defect structure group, and the first L-shaped defect structure group includes three Two first L-shaped defective ground structures (6) arranged side by side, two second L-shaped defective ground structures (7) are arranged on both sides of the first L-shaped defective ground structure group, each first L-shaped The vertical end of the defective ground structure (6) is in contact with one side edge of the second metal printing layer (3), and the vertical end of each second L-shaped defective ground structure (7) is in contact with the second metal printing layer (3) One side edge contact, characterized in that: the length (m1) of the vertical groove of each first L-shaped defective ground structure (6) is 11.5mm, and the vertical groove of each first L-shaped defective ground structure (6) The width (W1) of the groove is 2.4mm, the length (m2) of the horizontal groove of each first L-shaped defect ground structure (6) is 4mm, the width of the horizontal groove of each first L-shaped defect ground structure (6) (W2) is 3mm, the length (m3) of the vertical groove of each second L-shaped defective ground structure (7) is 8mm, the width (W3) of the vertical groove of each second L-shaped defective ground structure (7) ) is 2.4mm, the length (m4) of the horizontal groove of each second L-shaped defective ground structure (7) is 4mm, and the width (W4) of the horizontal groove of each second L-shaped defective ground structure (7) is 2.2 mm. 2. A kind of half-mode substrate integrated waveguide bandpass filter loaded with an L-shaped defect ground structure according to claim 1, characterized in that: each balanced microstrip line (4) consists of the first rectangular structure segment (4- 1), the right-angled trapezoidal segment (4-2) and the second rectangular structural segment (4-3) are sequentially connected from end to end. 3. according to claim 2, a kind of half-mode substrate integrated waveguide bandpass filter loaded with L-shaped defect ground structure is characterized in that: the width of the first rectangular structure section (4-1) is 1.9mm, the second The width of the rectangular structure section (4-3) is 5mm, the length of the short base of the right-angled trapezoidal section (4-2) is 1.9mm, the length of the long base of the right-angled trapezoidal section (4-2) is 5mm, and the length of the right-angled trapezoidal section (4-2) is 5mm. The length of segment (4-2) is 60 mm. 4. according to claim 1, a kind of half-mode substrate integrated waveguide bandpass filter loaded with L-shaped defect ground structure is characterized in that: the length of the dielectric substrate (2) is 270mm, and the width of the dielectric substrate (2) is 32.8mm, the thickness of the dielectric substrate (2) is 0.5mm, and the dielectric constant of the dielectric substrate (2) is 2.2. 5. A half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded structure according to claim 1, characterized in that: the length of the first metal printing layer (1) is 120mm, and the first metal printing layer (1) has a width of 32.8 mm, the thickness of the first metal printing layer (1) is 0.018 mm to 0.035 mm, the length of the second metal printing layer (3) is 270 mm, and the width of the second metal printing layer (3) is 32.8mm, and the thickness of the second metal printing layer (3) is 0.018mm-0.035mm. 6. A half-mode substrate integrated waveguide bandpass filter with an L-shaped defect-loaded ground structure according to claim 1, characterized in that: the diameter of each metallized via hole (5) is 1.6 mm, and two adjacent The center-to-center distance between the metallized via holes (5) is 2.5mm. 7. A half-mode substrate-integrated waveguide bandpass filter loaded with an L-shaped defect ground structure according to claim 1, characterized in that the distance between two adjacent first L-shaped defect ground structures (6) (J) is 15 mm, and the distance (J) between two adjacent second L-shaped defect ground structures (7) is 15 mm.