JP2020510326A - Multilayer chip bandpass filter - Google Patents

Abstract

The present invention provides a multilayer chip bandpass filter including a ceramic substrate and a sixth-order resonator, each resonator being a three-layer strip line resonator, and among the sixth-order resonators, first-order and third-order resonators. The 5th and 5th stripline resonators are located on the lower plane, the 2nd, 4th and 6th stripline resonators are located on the upper plane, and the multilayer chip bandpass filter is composed of the 2nd and 4th stripline resonators. A Z-type coupling line that cross-couples with the strip line resonator is further provided. The present invention installs a 6th order 3 layer stripline resonator, and the 3 layer stripline of each resonator has two additional plates so that the length of the resonator is much smaller than 1/4 wavelength. Form a loading capacitor. In order to utilize the space in the vertical direction, a sixth-order resonator is installed on two planes having different heights to secure the amount of coupling and to shorten the distance in the horizontal direction. , Higher integration, smaller size, less insertion loss in pass band, higher suppression in stop band, and higher reliability.

Description

  The present invention relates to the field of filters, and more particularly, to multilayer chip bandpass filters.

  As an important signal frequency selection and filtering interferer, bandpass filters directly affect the signal transmission quality of the entire system in microwave and millimeter wave systems such as communications, radar and the like. As electronic systems continue to evolve toward higher frequencies, higher integration, and higher performance, filter miniaturization has become a hot spot in academic and industrial research. By employing planar integration techniques (eg, printed circuit boards (PCBs) and integrated passive devices (IPDs)) and lamination techniques (eg, low temperature co-fired ceramics (LTCC)), filters can be made even smaller. The former has a large high frequency loss and a low filter quality factor (Q value), which limits its application to high frequency and high performance cases to some extent. The latter is widely used in multi-chip modules and microwave / millimeter wave systems due to its three-dimensional (3D) integration advantages and excellent material properties.

  A multilayer chip structure of a multilayer stripline resonator is preferred because of its advantages such as simple structure, high design freedom, and relatively easy processing. A current multilayer chip bandpass filter generally arranges multilayer stripline resonators on the same horizontal plane, which is a so-called “coplanar integration”. This structure uses a multi-layer stripline to increase the load capacitance, thereby realizing a quarter-wave resonator with a shorter stripline and greatly reducing the size of the filter.

  However, since the coupling between the resonators is mainly determined by their space separation, adopting the coplanar integration method limits the further miniaturization of the multilayer chip bandpass filter.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a multilayer chip bandpass filter for solving the problem of a large multilayer chip bandpass filter in the prior art.

  To achieve the above object, the solution of the technology adopted by the present invention is as follows. Provided is a multilayer chip bandpass filter, comprising: a ceramic substrate; a sixth-order resonator disposed on the ceramic substrate; and input terminals and output terminals respectively disposed on both ends of the ceramic substrate. Each of the resonators is a three-layered strip line resonator, and is installed extending along the width direction of the ceramic base. The sixth-order resonator is a primary stripline resonator, a secondary stripline resonator, a third-order stripline resonator, a fourth-order stripline resonator, and a fifth-order stripline resonator that are sequentially installed along the length direction of the ceramic base. A first stripline resonator, a third stripline resonator, and a fifth stripline resonator including a stripline resonator and a sixth-order stripline resonator, wherein the first stripline resonator, the third-order stripline resonator, and the fifth-order stripline resonator are located on a lower plane; The resonator, the fourth-order stripline resonator, and the sixth-order stripline resonator are located on an upper plane, and the lower plane is below the upper plane along a height direction of the ceramic base, and A stripline resonator is connected to the input terminal, and the sixth-order stripline resonator is connected to the output terminal. The multilayer chip bandpass filter further includes the Z-type coupling line cross-coupled between the secondary stripline resonator and the quaternary stripline resonator, and the Z-type coupling line extends in a width direction of the ceramic base. A second segment and a first segment extending along the length of the ceramic base, and a third segment extending along the length of the ceramic substrate. The first segment is connected to both ends of the third segment, respectively, the second segment and the first segment are respectively located on both sides of the third segment, and the second segment is connected to the third segment. The first segment is located above the secondary stripline resonator, and the first segment is located above the quaternary stripline resonator. It is a filter.

  Further, the three layers of strip lines of each resonator have the same interlayer spacing, and the uppermost layer strip line and the lowermost layer strip line are arranged mirror-symmetrically with respect to the intermediate layer strip line. One end of the strip line of the intermediate layer is grounded, the other end of the strip line of the intermediate layer is suspended, and is close to the ground of the strip line of the intermediate layer of the uppermost layer. The other end of the strip line of the uppermost layer is grounded, and the end of the lowermost layer strip line near the ground of the intermediate layer strip line is fishing, and the lower end of the strip line is grounded. Is grounded.

  Further, each of the resonators further includes a protruding strip corresponding to a dangling end of the strip line of each layer, wherein the protruding strip and the corresponding dangling end are spaced apart from each other, Both strips are grounded.

  Further, the multilayer chip bandpass filter further includes two ground strips provided on both left and right sides of the ceramic base, respectively, wherein each of the ground strips is connected to an adjacent one of the protruding strips. The ground terminal is connected to the adjacent ground strip.

  Further, the multilayer chip bandpass filter further includes an upper ground plate provided above the ceramic base, and a lower ground plate provided below the ceramic base, wherein the lower ground plate is provided below the ceramic base. The distance to the ground plane is substantially the same as the distance from the upper plane to the upper ground plane.

Further, upper notches for forming a dielectric region are provided on both sides of the upper ground plate, respectively, and a dielectric region for forming a dielectric region is formed on both sides of the lower ground plate. A lower notch is provided.
Further, the primary stripline resonator and the input terminal are disposed at an interval, and the sixth stripline resonator and the output terminal are disposed at an interval. The pass filter further includes a first tap connecting the primary stripline resonator to the input terminal, and a second tap connecting the sixth stripline resonator to the output terminal.

  Further, the width of the connection point between the first tap and the input terminal gradually contracts in a direction away from the input terminal from the input terminal, and the width of the connection point between the second tap and the output terminal. Gradually shrinks in a direction away from the output terminal from the output terminal.

Further, the first tap is a single-layer folded strip line, and the second tap is a single-layer folded strip line.
Further, the length of each resonator is different.

  The beneficial effects of the multilayer chip bandpass filter provided by the present invention are as follows. Compared with the prior art, the present invention provides a three-layer stripline resonator of each resonator such that the length of the resonator is much smaller than a quarter wavelength by installing a sixth-order three-layer stripline resonator. The lines form two additional plate loading capacitors. In order to make full use of the space in the vertical direction, a sixth-order resonator is provided on two planes having different heights to secure the coupling amount and shorten the horizontal space, thereby enabling the multilayer chip bandpass to be formed. Filters are more integrated, smaller, have lower insertion loss in the passband, have higher suppression in the stopband, and are more reliable. The process is simple and the cost is low.

  In order to more clearly explain the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below. Are only some embodiments of the present invention, and those skilled in the art can obtain other drawings from these drawings without creative efforts.

1 is a schematic perspective view of a multilayer chip bandpass filter provided according to an embodiment of the present invention; FIG. 3 is a schematic plan view of a multilayer chip bandpass filter provided according to an embodiment of the present invention. 1 is a schematic front view of a multilayer chip bandpass filter provided according to an embodiment of the present invention. FIG. 2 is a schematic diagram of an equivalent circuit structure of a multilayer chip bandpass filter provided according to an embodiment of the present invention. FIG. 4 is a schematic diagram showing a simulation result of a multilayer chip bandpass filter employed according to an embodiment of the present invention.

  Among them, the main reference numerals of the respective drawings in the drawings are as described in the reference numerals.

  In order to make the technical problems, technical solutions, and beneficial effects to be solved by the present invention clearer, the present invention will be described in more detail with reference to the drawings and embodiments. It should be understood that the specific examples described herein are merely illustrative of the invention and are not intended to limit the invention.

  When one element is said to be "fixed" or "installed" on another element, it may be directly on another element or indirectly on another element Note that you can When one element is said to be "connected" to another element, it may be connected directly to another element or indirectly to another element.

  Also, the terms "first" and "second" are merely descriptive of the purpose and indicate or imply relative importance, or implicit in the number of technical features indicated. Should not be construed as indicating. Thus, features defining "first" and "second" may include explicitly or implicitly one or more of the features. In the description of the present invention, “plurality” means two or more unless otherwise specified. The meaning of "slightly" is 1 or more unless otherwise specified.

  In the description of the present invention, the terms “center”, “length”, “width”, “thickness”, “top”, “bottom”, “front”, “back”, “left”, “right”, “ The orientation or positional relationship indicated by “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, etc. is based on the orientation or positional relationship shown in the drawings, which facilitates description of the present invention. It is merely to simplify the description and not to imply or imply that the device or component shown has a particular orientation and must be configured or operated in a particular orientation. Therefore, they should not be construed as limiting the invention.

  In the description of the present invention, unless otherwise explicitly defined and limited, the terms "attach", "couple", and "connect" are to be understood broadly, e.g. Connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium. May be internal communication of two elements or interaction of two elements. Those skilled in the art can understand the specific meaning of the above terms in the present invention on a case-by-case basis.

  For convenience of description, three coordinate axes orthogonal to each other on a defined space are an X axis, a Y axis, and a Z axis, respectively, where the X axis and the Y axis are two coordinate axes orthogonal to each other on the same horizontal plane. , Z axis are vertical coordinate axes. The X-axis, the Y-axis, and the Z-axis are disposed so as to be orthogonal to each other in three planes of an XY plane, a YZ plane, and an XZ plane. The direction is defined as the Y axis, the height direction is defined as the Z axis, the horizontal direction is defined as a direction parallel to the Y axis, and the vertical direction is defined as a direction parallel to the Z axis.

  Referring to FIGS. 1 to 3 together, a multilayer chip bandpass filter provided by the present invention will be described. The multilayer chip bandpass filter includes a ceramic base 11, a sixth-order resonator 20, an input terminal 12, an output terminal 13, and a Z-type coupling line 31. The input terminal 12 and the output terminal 13 are provided at both ends of the ceramic base 11, respectively, and the sixth-order resonator 20 and the Z-type coupling line 31 are both provided on the ceramic base 11. Each resonator 20 is installed so as to extend along the width direction of the ceramic base 11, and each resonator 20 is a three-layer strip line resonator. By forming two additional plate loading capacitors in the stripline 200, the resonator 20 can be much smaller in length than a quarter wavelength, and furthermore, the multilayer chip bandpass filter can be switched to the C band (operating frequency is 4-8 GHz). Frequency band). The sixth-order resonator 20 includes a first-order stripline resonator 21, a second-order stripline resonator 22, a third-order stripline resonator 23, a fourth-order stripline resonator, a fifth-order stripline resonator, and a sixth-order stripline resonator. including. The first stripline resonator 21, the second stripline resonator 22, the third stripline resonator 23, the fourth stripline resonator 24, the fifth stripline resonator 25, and the sixth stripline resonator 26 are made of a ceramic substrate. The first strip line resonator 21 is connected to the input terminal 12, and the sixth strip line resonator 26 is connected to the output terminal 13. The primary stripline resonator 21, the tertiary stripline resonator 23, and the fifth-order stripline resonator 25 are located on the lower plane 42, and the secondary stripline resonator 22, the fourth-order stripline resonator 24, and the sixth-order strip The line resonator 26 is located on the upper plane 41, and the lower plane 42 is below the upper plane 41 along the height direction of the ceramic base 11, thereby saving a space in the vertical direction (the height direction of the ceramic substrate 11). By making full use of it, further reducing the lateral spacing, increasing the degree of integration and miniaturizing, and controlling the adjacent coupling by the width of each resonator 20 and the distance between two adjacent resonators 20, Adjacent coupling between the 20 is achieved by a broadside coupling. The Z-shaped coupling line 31 is used to cross-couple the secondary stripline resonator 22 and the quaternary stripline resonator 24, and the Z-shaped coupling line 31 extends along the width direction of the ceramic base 11. The first segment 311 and the second segment 312 are provided. The third segment 313 is provided to extend along the length direction of the ceramic base 11. The second segment 312 and the first segment are provided. 311 is connected to both ends of the third segment 313, the second segment 312 and the first segment 311 are respectively located on both sides of the third segment 313, and the second segment 312 is a secondary strip line. The first segment 311 is located above the resonator 22, and the first segment 311 is located above the fourth stripline resonator 24. Therefore, by adjusting the length and width of the second segment 312, the first segment 311 and the third segment 313, the coupling amount can be controlled. This structure can ensure the same coupling amount of the sixth-order resonator 20.

As shown in FIG. 4, in the equivalent circuit of the multilayer chip bandpass filter of the present invention, each resonator 20 is equivalent to one strip line resonator plus its loading capacitor, that is, the primary strip line resonator 21 is a strip line resonator. The secondary stripline resonator 22 is equivalent to the stripline resonator R2 plus the capacitor C2, the tertiary stripline resonator 23 is equivalent to the stripline resonator R3 plus the capacitor C3, The fourth-order stripline resonator 24 is equivalent to a stripline resonator R4 plus a capacitor C4, the fifth-order stripline resonator 25 is equivalent to a stripline resonator R5 plus a capacitor C5, and the sixth-order stripline resonator 26 is a stripline. Equivalent to a resonator R6 plus a capacitor C6, Filtering layer chip bandpass filter is implemented by coupling the resonance mechanism, where _is the _{M 12, M 23, M 34} , M 45, M 56 is adjacent _{bond, M 24} is a cross-linked, whereby As a result, the same coupling amount is secured, the insertion loss in the pass band is reduced, the suppression of the stop band is improved, and the reliability is high.

  In the multilayer chip bandpass filter provided by the present invention, the present invention provides a 6th-order three-layer stripline 200 resonator in which the length of the resonator 20 is smaller than 1/4 wavelength compared to the prior art. As much smaller, the three layer stripline 200 of each resonator 20 forms two additional plate loading capacitors. In order to make full use of the space in the vertical direction, the sixth-order resonator 20 is installed on two planes having different heights, and the same coupling amount is secured and the horizontal distance is shortened. Bandpass filters have the characteristics of higher integration, smaller size, lower passband insertion loss, higher suppression of stopband, higher reliability, etc., and when processed with low-temperature co-fired ceramic technology. The processing process is simple and the cost is low.

  Further, referring to FIGS. 1 to 3 together, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the three layers of each resonator 20 have the same interlayer spacing. In addition, the uppermost stripline 202 and the lowermost stripline 203 are arranged mirror-symmetrically with respect to the intermediate stripline 201. In each resonator 20, one end of the intermediate-layer strip line 201 is grounded, the other end of the intermediate-layer strip line 201 is suspended, and the intermediate-layer strip line 201 of the uppermost-layer strip line 202 is suspended. The end near the ground is suspended, the other end of the uppermost stripline 202 is grounded, and the end of the lowermost stripline 203 near the ground of the intermediate stripline 201 is suspended. The other end of the lowermost strip line 203 is grounded. Not only can processing and manufacturing be facilitated and design is easy, but also symmetry of each resonator 20 can be ensured and insertion loss in the pass band can be reduced.

  Further, the strip line 201 of the intermediate layer of the primary strip line resonator 21, the strip line 201 of the intermediate layer of the tertiary strip line resonator 23, and the strip line 201 of the intermediate layer of the fifth strip line resonator 25 are the lower plane 42. Located in. The uppermost stripline 202 of the primary stripline resonator 21, the uppermost stripline 202 of the tertiary stripline resonator 23, and the uppermost stripline 202 of the fifth-order stripline resonator 25 are located on the same plane. . The lowermost stripline 203 of the primary stripline resonator 21, the lowermost stripline 203 of the tertiary stripline resonator 23, and the lowermost stripline 203 of the fifth-order stripline resonator 25 are located on the same plane. . At the same time, the strip line 201 in the middle layer of the secondary strip line resonator 22 and the strip line 201 in the middle layer of the fourth strip line resonator 24 and the strip line 201 in the middle layer of the sixth strip line resonator 26 are lower planes. 42. The uppermost stripline 202 of the secondary stripline resonator 22, the uppermost stripline 202 of the fourth stripline resonator 24, and the uppermost stripline 202 of the sixth stripline resonator 26 are located on the same plane. . The lowermost stripline 203 of the secondary stripline resonator 22, the lowermost stripline 203 of the fourth stripline resonator 24, and the lowermost stripline 203 of the sixth stripline resonator 26 are located on the same plane. . The plane where the lowermost stripline 203 of the secondary stripline resonator 22 is located is above the plane where the uppermost stripline 202 of the primary stripline resonator 21 is located, that is, each plane corresponding to the upper plane 41. The strip line 200 of each layer in the resonator 20 is located above the strip line 200 of each layer in each resonator 20 corresponding to the lower plane 42 as a whole.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, in each resonator 20, the width of the strip line 201 of the intermediate layer is the uppermost layer. , And the width of the intermediate-layer strip line 201 is smaller than that of the lowermost-layer strip line 203, whereby the symmetry of each resonator 20 is firmly secured, and the insertion loss in the pass band is reduced.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, each resonator 20 corresponds to a suspended end of the strip line 200 of each layer. It further includes protruding strips 204, and each protruding strip 204 is spaced apart from the corresponding suspended end, and each protruding strip 204 is grounded, thereby increasing the consistency of the strip lines 200 of each layer and increasing the passband. To reduce the insertion loss.

  Further, referring to FIGS. 1 to 3 together, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the multilayer chip bandpass filter is installed on each of the left and right sides of the ceramic base 11. And each ground strip 14 is connected to an adjacent projecting strip 204, and the ground terminal of each stripline 200 is connected to an adjacent ground strip 14, i.e., in each resonator 20. Each protruding strip 204 is connected to the adjacent ground strip 14, and the ground terminal of the strip line 200 of each layer in each resonator 20 is connected to the adjacent ground strip 14. The ground strip 14 is installed so that each protruding strip 204 is grounded and one end of each strip line 200 is grounded.

  Further, referring to FIGS. 1 to 3 together, in one specific embodiment of the multilayer chip bandpass filter provided by the present invention, each of the ground strips 14 and the input terminals 12 use a non-through form, that is, The input terminals 12 are displaced from the respective ground strips 14. For example, as shown in FIG. Have been. Each of the ground strips 14 and the output terminals 13 use a non-penetration type, that is, the output terminal 13 and each of the ground strips 14 are disengaged. For example, as shown in FIG. The output terminal 13 is provided along the height direction of the ceramic base 11. Thereby, the probability of occurrence of a short circuit due to the distance between the input terminal 12, the output terminal 13 and the corresponding ground strip 14 being too small can be reduced.

  Still referring to FIGS. 1-3, in one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the length of each resonator 20 is different, thereby achieving asynchronous tuning. Further, the insertion loss in the pass band is reduced, and the suppression and reliability of the stop band are improved.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the strip line 201 of the primary strip line resonator 21 is connected to the input terminal 12. The strip line 201 of the sixth-order strip line resonator 26 is connected to the output terminal 13, thereby reducing the insertion loss in the pass band.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the multilayer chip bandpass filter includes an upper side mounted on a ceramic base 11. And a lower ground plate 32 provided below the ceramic base 11. The distance from the lower plane 42 to the lower ground plate 32 is from the upper plane 41 to the upper ground plate 33. , So as to assure longitudinal symmetry as much as possible and to reduce losses due to surface roughness of the ground plane. Further, "substantially equal" means that the distance from the lower plane 42 to the lower ground plane 32 is equal to the distance from the upper plane 41 to the upper ground plane 33 as much as possible, and it goes without saying that a manufacturing error is allowed.

  Referring to FIGS. 1 to 3 together, as a specific embodiment of the multilayer chip bandpass filter provided by the present invention, upper cuts for forming dielectric regions on both sides of the upper ground plate 33 respectively. A notch 331 is provided, and a lower notch 321 for forming a dielectric region is provided on each side edge of the lower ground plate 32, thereby reducing insertion loss in a pass band. Further, the length of each upper notch 331 in the upper ground plate 33 is 0.75 mm, and the width of each upper notch 331 is 0.2 mm. The length of each lower notch 321 in the lower ground plate 32 is 0.75 mm, and the width of each lower notch 321 is 0.2 mm.

  Further, referring to FIGS. 1 to 3 together, as a specific embodiment of the multilayer chip bandpass filter provided by the present invention, the primary stripline resonator 21 and the input terminal 12 are installed at an interval. The sixth-order stripline resonator 26 and the output terminal 13 are arranged at an interval to suppress unnecessary parasitic modes.

  The multilayer chip bandpass filter further includes a first tap 34 connecting the primary stripline resonator 21 and the input terminal 12 and a second tap 35 connecting the sixth stripline resonator 26 and the output terminal 13. Including. The external quality factor (external Q value) is determined mainly by the splicing position of the first tap 34 and the primary strip line resonator 21 and the splicing position of the second tap 35 and the sixth strip line resonator 26. Thereby improving the external quality factor.

  Further, referring to FIGS. 1 to 3 together, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the width of the connection point between the first tap 34 and the input terminal 12 is It gradually contracts in a direction away from the input terminal 12 from the input terminal 12. The width of the connection portion between the second tap 35 and the output terminal 13 gradually contracts in a direction away from the output terminal 13 and away from the output terminal 13. This ensures the reliability of the connection of the terminal electrodes and reduces the influence of the parasitic parameters.

  Further, referring to FIGS. 1 to 3 together, in one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the first tap 34 is a single-layer folded strip line and the second tap 34 is The tap 35 is a single-layer folded strip line, and further secures the connection of the terminal electrode and reduces the influence of the parasitic parameter.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the length of the ceramic substrate 11 is 3.2 mm, and the length of the ceramic substrate 11 is 3.2 mm. The width is 1.6 mm and the height of the ceramic base 11 is 0.9 mm, thereby reducing the size of the multilayer chip bandpass filter.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, an input terminal 12 and an output terminal 13 are provided at both ends of a ceramic base 11, respectively. Ground strips 14 are provided on both left and right sides of the ceramic base 11, respectively, and two ground terminals are formed on each of the two ground strips 14.

  1 to 3, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the length of the input terminal 12 along the Y-axis direction is 0.4 mm. That is, the width of the input terminal 12 is 0.4 mm. The length of the output terminal 13 along the Y-axis direction is 0.4 mm, that is, the width of the output terminal 13 is 0.4 mm. The length of the ground strip 14 in the X direction is 2.7 mm, that is, the length of the ground strip 14 is 2.7 mm.

  Furthermore, referring to FIGS. 1 to 3 together, as a specific embodiment of the multilayer chip bandpass filter provided by the present invention, the dielectric constant of the ceramic material in the ceramic substrate 11 is 11.0 to 15.0. , And the dielectric loss coefficient tan α ≦ 0.002. That is, the dielectric constant of the ceramic material of the manufactured ceramic substrate 11 is 11.0-15.0, and the dielectric loss coefficient tan α ≦ 0.002, thereby improving the reliability and reducing the insertion loss in the pass band. I do.

  Referring to FIGS. 1 to 3 together, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, each of the resonators 20 is made of metallic silver in order to improve conductivity. Manufactured. The strip line 200 of each layer of each resonator 20 is made of metallic silver. Further, the thickness of the silver layer of the strip line 200 in each layer of each resonator 20 is 10 ± 3 μm. Further, each protruding strip 204 of each resonator 20 is made of metallic silver. The thickness of the silver layer of each projecting strip 204 of each resonator 20 is 10 ± 3 μm.

Further, in order to improve the conductivity, each of the first taps 34 is made of metallic silver. Further, the thickness of the silver layer of the first tap 34 is 10 ± 3 μm.
Further, to improve conductivity, each of the second taps 35 is made of metallic silver. Further, the thickness of the silver layer of the second tap 35 is 10 ± 3 μm.
Further, in order to improve conductivity, the upper ground plate 33 and the lower ground plate 32 are both made of metallic silver. Further, the thickness of the silver layer of the upper ground plate 33 is 10 ± 3 μm. The thickness of the silver layer of the lower ground plate 32 is 10 ± 3 μm.

  Further, referring to FIGS. 1 to 3 together, as a specific embodiment of the multilayer chip bandpass filter provided by the present invention, the input terminal 12 is made of metallic silver to improve conductivity. The thickness of the silver layer of the input terminal 12 is 15 ± 3 μm. The output terminal 13 is made of metallic silver to improve conductivity. The thickness of the silver layer of the output terminal 13 is 15 ± 3 μm.

  Further, referring to FIGS. 1 to 3 together, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, each ground strip 14 is made of metallic silver to improve conductivity. . The thickness of the silver layer of each ground strip 14 is 15 ± 3 μm.

  Further, referring to FIG. 1 to FIG. 5, as one specific embodiment of the multilayer chip bandpass filter provided by the present invention, the operating frequency range of the multilayer chip bandpass filter is 5500 ± 500 MHz. That is, the operating frequency range of the multilayer chip bandpass filter is 5000 MHz to 6000 MHz.

  The multilayer chip bandpass filter can be manufactured using an LTCC process. For example, at the time of molding, from the bottom to the top, first, a blank layer is laminated with a blank dielectric film, and the metal pattern of each layer is formed from the bottom to the top. The lower grounding plate 32, each resonator 20, the first tap 34, the second tap 35, and the upper grounding plate 33 are manufactured by printing sequentially, and then manufactured by laminating a part of the blank dielectric film. I do. After sintering, the external ports are printed using screen printing techniques to produce the ground strip 14, input terminal 12, and output terminal 13, respectively.

Still referring combined to FIGS. 1-5, as a simulation simulation result diagram of the laminated chip bandpass filter provided by the present invention, S ₁₁ in the figure is a return loss curve at each frequency of the simulation, S ₂₁ is It is an insertion loss curve at each frequency of the simulation. As can be seen from the simulation results, the passband range of the multilayer chip bandpass filter is 5000 MHz to 6000 MHz, the insertion loss of the passband is less than 2.5 dB, and the return loss The amount is less than 19 dB, and the suppression of the stopband is greater than 33 dB in the DC-4600 MHz frequency band and greater than 32 dB in the 6400-12000 MHz frequency band.

  The multilayer chip bandpass filter of the present invention can be applied to the field of C-band front-end modules, and can also be applied to fields such as microwave communication, radar systems, and electronic countermeasures.

  The above description is only preferred embodiments of the present invention, and the present invention is not limited to these, and any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and principle of the present invention are described below. Either should fall within the protection scope of the present invention.

Reference Signs List 11 ceramic substrate 12 input terminal 13 output terminal 14 ground strip 20 resonator 21 primary stripline resonator 22 secondary stripline resonator 23 tertiary stripline resonator 24 quaternary stripline resonator 25 quintic stripline resonator 26 Sixth-order stripline resonator 200 Stripline 201 Intermediate layer stripline 202 Uppermost layer stripline 203 Lowermost layer stripline 204 Projecting strip 31 Z-shaped coupling line 311 First segment 312 Second segment 313 Third Segment 32 Lower grounding plate 321 Lower notch 33 Upper grounding plate
331 Upper cutout 34 First tap 35 Second tap 41 Upper plane 42 Lower plane

Claims (10)

  A multilayer chip bandpass filter, comprising: a ceramic substrate; a sixth-order resonator disposed on the ceramic substrate; and input terminals and output terminals disposed on both ends of the ceramic substrate, respectively, wherein each of the resonators is Each of the resonators is a strip line resonator having three layers, and the sixth resonator is arranged along the length direction of the ceramic base. And a primary stripline resonator, a secondary stripline resonator, a tertiary stripline resonator, a quaternary stripline resonator, a quintic stripline resonator, and a quaternary stripline resonator, which are sequentially installed. The primary stripline resonator, the tertiary stripline resonator, and the fifth-order stripline resonator are located on a lower plane, and the secondary stripline The resonator, the fourth-order stripline resonator, and the sixth-order stripline resonator are located on an upper plane, and the lower plane is below the upper plane along a height direction of the ceramic base, and The stripline resonator is connected to the input terminal, the sixth-order stripline resonator is connected to the output terminal, and the multilayer chip bandpass filter includes the second-order stripline resonator and the fourth-order stripline resonator. The ceramic substrate further includes a Z-shaped coupling line cross-coupled to a stripline resonator, the Z-shaped coupled line extending along a width direction of the ceramic base, a second segment and a first segment, and the Z-shaped coupling line. A third segment extending along a length direction of the ceramic base, wherein the second segment and the first segment are each provided with the third segment; The second segment and the first segment are respectively located on both sides of the third segment, and the second segment is located above the secondary stripline resonator. And wherein the first segment is located above the fourth-order stripline resonator.   The three layers of strip lines of each resonator have the same interlayer spacing, and the uppermost layer strip line and the lowermost layer strip line are arranged mirror-symmetrically with respect to the intermediate layer strip line. One end of the strip line of the layer is grounded, the other end of the strip line of the intermediate layer is suspended, and the end of the strip line of the uppermost layer near the ground of the strip line of the intermediate layer is suspended in the air. The other end of the uppermost layer of the stripline is grounded, the lowermost layer of the intermediate layer of the stripline near the ground is suspended, and the lowermost layer of the stripline is suspended. The multilayer chip bandpass filter according to claim 1, wherein the other end of the filter is grounded.   Each of the resonators further includes a protruding strip corresponding to a suspended end of the strip line of each layer, and the protruding strip and the corresponding suspended end are disposed at an interval, and each of the protruding strips is The multilayer chip bandpass filter according to claim 2, wherein the multilayer chip bandpass filter is grounded.   The multilayer chip bandpass filter further includes two ground strips respectively installed on both left and right sides of the ceramic substrate, each of the ground strips being connected to the adjacent protruding strip, and a ground terminal of each of the strip lines. 4. The multilayer chip bandpass filter according to claim 3, wherein the filter is connected to the adjacent ground strip.   The multilayer chip bandpass filter further includes an upper ground plate provided above the ceramic base, and a lower ground plate provided below the ceramic base, wherein the lower ground plate extends from the lower plane to the lower ground plate. The multilayer chip bandpass filter according to any one of claims 1 to 4, wherein a distance is substantially the same as a distance from the upper plane to the upper ground plate.   Upper notches for forming a dielectric region are respectively provided on both sides of the upper grounding plate, and lower notches for forming a dielectric region respectively on both sides of the lower grounding plate. The multilayer chip band-pass filter according to claim 5, wherein a filter is provided.   The primary stripline resonator and the input terminal are disposed at an interval, and the sixth stripline resonator and the output terminal are disposed at an interval. And further comprising: a first tap connecting the primary stripline resonator to the input terminal; and a second tap connecting the sixth stripline resonator to the output terminal. Item 5. The multilayer chip bandpass filter according to any one of Items 1 to 4.   The width of the connection point between the first tap and the input terminal gradually contracts in a direction away from the input terminal from the input terminal, and the width of the connection point between the second tap and the output terminal is The multilayer chip bandpass filter according to claim 7, wherein the filter gradually shrinks in a direction away from the output terminal from the output terminal.   The multilayer chip bandpass filter according to claim 7, wherein the first tap is a single-layer folded strip line, and the second tap is a single-layer folded strip line.   The multilayer chip bandpass filter according to any one of claims 1 to 4, wherein each resonator has a different length.

Images