Filtering power division circularly polarized antenna module based on LTCC (Low Temperature Co-Fired Ceramic)

Abstract

The invention discloses a filtering power division circularly polarized antenna module based on LTCC (Low Temperature Co-Fired Ceramic). Comprising a ceramic dielectric module, a filter, a power divider, a phase shifter, a patch antenna and a quasi-coaxial transmission structure, the ceramic dielectric module is arranged at the periphery of the filter, the power divider, the phase shifter, the patch antenna and the quasi-coaxial transmission structure; the filter is connected with the power divider, the power divider is connected with the phase shifter, and the phase shifter is connected with the patch antenna; according to the invention, multiple layers of circuits are superposed in the ceramic dielectric module, a complex three-dimensional circuit design is realized, passive elements such as a power divider and a filter are integrated, and the requirements of high frequency, large bandwidth and low power consumption are met.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a LTCC-based filtering power division circularly polarized antenna module. Background Art

[0002] LTCC (Low Temperature Co-fired Ceramic) technology is a process for manufacturing high-frequency electronic circuits and devices, and is widely used in the manufacture of radio frequency, microwave circuits and other electronic components. LTCC technology can achieve three-dimensional structural integration of circuits by sintering ceramic substrates and conductive materials embedded therein at low temperatures (usually below 850°C). This technology is particularly suitable for high-density, compact electronic devices, and can meet the requirements of miniaturization, low loss and high performance.

[0003] At present, the development of 6G technology and satellite Internet technology has put forward higher requirements for the miniaturization of RF devices, and the communication frequency has gradually developed towards the higher frequency Ka, Q and U bands. In these frequency bands, the wavelength is shorter, resulting in a relatively smaller device size and a more compact design of components such as antennas. Therefore, the design of RF devices must achieve miniaturization and high efficiency through high-integration technology in order to meet the requirements of 6G and satellite communications for high-frequency transmission. At the same time, these technologies will be more widely used in portable devices such as smartphones in the future, which have extremely high requirements for miniaturized and lightweight transceiver components. However, existing antenna modules are difficult to meet the requirements of high frequency, large bandwidth and low power consumption while meeting the requirements of miniaturization and lightweight. Summary of the invention

[0004] The main technical problem solved by the present application is to provide a LTCC-based filtering power division circularly polarized antenna module, which solves the problem that existing antenna modules are difficult to meet the requirements of high frequency, large bandwidth and low power consumption while meeting the requirements of miniaturization and lightweight.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is to provide a LTCC-based filtering power-dividing circularly polarized antenna module, including a ceramic dielectric module, a filter, a power divider, a phase shifter, a patch antenna and a quasi-coaxial transmission structure; the ceramic dielectric module is arranged around the filter, the power divider, the phase shifter, the patch antenna and the quasi-coaxial transmission structure; the filter is connected to the power divider, the power divider is connected to the phase shifter, and the phase shifter is connected to the patch antenna; the filter is arranged at the lower part and the middle part of the ceramic dielectric module, The filter includes a plurality of cascaded resonant cavities for filtering signals; the power divider and the phase shifter are arranged on the upper part of the ceramic dielectric module, the power divider is used to distribute power of the output signal of the filter, and the phase shifter is used to shift the phase of the output signal of the power divider; the patch antenna is arranged on the upper surface of the ceramic dielectric module, and the patch antenna is fed with dual ports through the output signal of the phase shifter to radiate circularly polarized electromagnetic waves; the quasi-coaxial transmission structure is arranged in the ceramic dielectric module and connects the filter and the power divider.

[0006] In some embodiments, the antenna module further includes a stripline feeding port, the stripline feeding port is disposed on a side of the ceramic dielectric module, and the stripline feeding port is connected to the filter through the quasi-coaxial transmission structure.

[0007] In some embodiments, the filter includes a first disc patch, a first stripline, a second disc patch, a second stripline and a plurality of metal ground plates, wherein the plurality of metal ground plates are stacked and arranged, from top to bottom, they are the first metal ground plate, the second metal ground plate, the third metal ground plate, the fourth metal ground plate, the fifth metal ground plate and the sixth metal ground plate, the first disc patch is connected to the first stripline, the first disc patch and the first stripline are arranged between the second metal ground plate and the third metal ground plate, the first end of the first stripline is adjacent to the stripline feeding port and is located at the edge of the ceramic dielectric module, the second end of the first stripline is located on the other side of the ceramic dielectric module and is adjacent to the middle of the ceramic dielectric module; the first disc patch is located on the upper side of the second end of the first stripline, ... A disc patch is connected to the second end of the first stripline through a first connecting through hole on the ceramic dielectric module, and the first stripline serves as the input end of the filter; the second disc patch is connected to the second stripline, and the second disc patch and the second stripline are arranged between the fifth metal ground plate and the sixth metal ground plate, the first end of the second stripline is on the same side as the first end of the first stripline, and is adjacent to the middle of the ceramic dielectric module, and the second end of the second stripline is on the same side as the second end of the first stripline, and is adjacent to the edge of the ceramic dielectric module; the second disc patch is located on the upper side of the second end of the second stripline, and the second disc patch is connected to the second end of the second stripline through a second connecting through hole on the ceramic dielectric module, and the second stripline serves as the output end of the filter.

[0008] In some embodiments, a plurality of metal through holes are provided on the ceramic dielectric module between the second metal grounding plate to the sixth metal grounding plate and between adjacent metal grounding plates, and the plurality of metal through holes constitute the resonant cavity; the plurality of metal through holes between the second metal grounding plate and the third metal grounding plate constitute the first resonant cavity, the first disk patch and the first strip line are located in the area enclosed by the first resonant cavity, the plurality of metal through holes between the third metal grounding plate and the fourth metal grounding plate constitute the second resonant cavity, the plurality of metal through holes between the fourth metal grounding plate and the fifth metal grounding plate constitute the third resonant cavity, and the plurality of metal through holes between the fifth metal grounding plate and the sixth metal grounding plate constitute the second resonant cavity. The fourth resonant cavity is formed by a metal through hole, the second disk patch and the second strip line are located in the area enclosed by the fourth resonant cavity; the third metal grounding plate is provided with a first metal window, the fourth metal grounding plate is provided with a second metal window, and the fifth metal grounding plate is provided with a third metal window; the first metal window and the third metal window have the same extension direction as the first strip line, and the extension direction of the second metal window is perpendicular to the extension direction of the first strip line; the first resonant cavity is coupled to the second resonant cavity through the first metal window, the second resonant cavity is coupled to the third resonant cavity through the second metal window, and the third resonant cavity is coupled to the fourth resonant cavity through the third metal window.

[0009] In some embodiments, the metal ground plate also includes a seventh metal ground plate, and the seventh metal ground plate is arranged on the upper side of the sixth metal ground plate. The quasi-coaxial transmission structure includes a quasi-coaxial inner conductor and a quasi-coaxial outer wall. The quasi-coaxial inner conductor and the quasi-coaxial outer wall through holes between the first metal ground plate and the second metal ground plate connect the stripline feeding port and the filter, and the quasi-coaxial inner conductor and the quasi-coaxial outer wall through holes arranged between the sixth metal ground plate and the seventh metal ground plate connect the filter and the power divider.

[0010] In some embodiments, the power divider includes an input branch, an impedance converter and an isolation resistor, wherein the input branch, the impedance converter and the isolation resistor are arranged between the sixth metal ground plate and the seventh metal ground plate, one end of the input branch is connected to the second strip line through the coaxial transmission structure, and the other end is connected to the impedance converter; the impedance converter includes a first impedance converter and a second impedance converter, wherein the first impedance converter and the second impedance converter are connected to the input branch, and the other end is connected to the phase shifter; the isolation resistor is arranged between the ends of the first impedance converter and the second impedance converter, and is adjacent to the phase shifter.

[0011] In some embodiments, a first metallized feed via and a second metallized feed via are provided on the upper portion of the ceramic dielectric module, the phase shifter includes a third stripline and a fourth stripline, the third stripline and the fourth stripline are provided between the sixth metal ground plate and the seventh metal ground plate, one end of the third stripline is connected to the first impedance transformer, and the other end is connected to the first metallized feed via, one end of the fourth stripline is connected to the second impedance transformer, and the other end is connected to the second metallized feed via, and the first metallized feed via and the second metallized feed via are connected to the patch antenna.

[0012] In some embodiments, the patch antenna is square, and the phase shifter outputs two signals with a phase difference of 90 degrees, which are fed to the patch antenna through the first metallized feeding through hole and the second metallized feeding through hole.

[0013] In some embodiments, the ceramic dielectric module includes multiple dielectric substrates, and the multiple dielectric substrates are stacked; there are 28 dielectric substrates, which are the first substrate to the twenty-eighth substrate from top to bottom, the filter is arranged at the third substrate to the twenty-first substrate, the power divider and the phase shifter are arranged at the twenty-second substrate to the twenty-third substrate, and the patch antenna is arranged on the upper surface of the twenty-eighth substrate; the first metal ground plate is arranged between the third substrate and the fourth substrate, the second metal ground plate is arranged between the fifth substrate and the sixth substrate, the third metal ground plate is arranged between the ninth substrate and the tenth substrate, the fourth metal ground plate is arranged between the thirteenth substrate and the fourteenth substrate, the fifth metal ground plate is arranged between the seventeenth substrate and the eighteenth substrate, and the sixth metal ground plate is arranged between the twenty-first substrate and the twenty-second substrate.

[0014] In some embodiments, the first substrate to the twenty-eighth substrate all use Ferro-A6M material with a relative dielectric constant of 5.9 and a loss tangent value of 0.001, the thickness of each layer of the dielectric substrate is 0.096 mm, and it is made by a low-temperature co-fired ceramic process; the radius R2 of the quasi-coaxial inner conductor is 0.024 mm, and the height is 0.384 mm, the radius R2 of the quasi-coaxial outer wall through hole is 0.024 mm, and the height is 0.192 mm, and the distance S2 between adjacent quasi-coaxial outer wall through holes is 0 .21mm; the distance between the quasi-coaxial inner conductor and the quasi-coaxial outer wall is 0.2mm; the thickness of the metal ground plate is 0.01mm; the radius R1 of the metal through hole is 0.075mm, the height is 0.384mm, and the distance between adjacent metal through holes is 0.3mm; the size of the isolation resistor is 0.1mm×0.18mm, the resistance is 100 ohms, and the radius of the first metallized feed through hole and the second metallized feed through hole is 0.06mm; the size of the patch antenna is 1.8 mm×1.8mm, the horizontal axis feeding position is 0.3mm from the center of the patch antenna, and the vertical axis feeding position is 0.45mm from the center of the patch antenna.

[0015] The beneficial effects of the present application are as follows: the present application discloses a filtering power-dividing circularly polarized antenna module based on LTCC, which superimposes multiple layers of circuits in a ceramic dielectric module, realizes a complex three-dimensional circuit design, and integrates passive components such as power dividers and filters, etc., to meet the requirements of high frequency, large bandwidth and low power consumption. And thanks to the high temperature resistance and thermal shock resistance of the ceramic dielectric module, it has good mechanical strength and is suitable for use in harsh environments. Compared with traditional circuit design, LTCC technology has significant miniaturization advantages, and can achieve high-density packaging and smaller circuit size. And through stripline feeding, it is easy to combine with other LTCC RF devices, and has good application potential in the satellite Internet communication wave frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a structural schematic diagram according to an embodiment of the present application; Figure 2 is a schematic diagram of the internal structure according to an embodiment of the present application; Figure 3 is a front structural diagram of the internal structure of a ceramic dielectric module according to an embodiment of the present application; Figure 4 is a schematic diagram of the connection structure in a ceramic dielectric module according to an embodiment of the present application; Figure 5 is a schematic diagram of a top view of the structure of a first metal grounding plate according to an embodiment of the present application; Figure 6is a schematic diagram of a top view of the structure of the second metal grounding plate according to an embodiment of the present application; Figure 7 is a schematic diagram of a top view of the structure of a third metal grounding plate according to an embodiment of the present application; Figure 8 is a schematic diagram of a top view of the structure of a fourth metal grounding plate according to an embodiment of the present application; Fig. 9 is a schematic diagram of a top view of the structure of a fifth metal grounding plate according to an embodiment of the present application; Fig.10 is a schematic diagram of a top view of the structure of a sixth metal grounding plate according to an embodiment of the present application; Fig.11 is a diagram of return loss and gain simulation results according to an embodiment of the present application; Fig.12 is a diagram of voltage standing wave ratio simulation results according to an embodiment of the present application; Fig.13 is a diagram of an axial ratio simulation result according to an embodiment of the present application; Fig.14 is a simulation result of the E-plane pattern according to an embodiment of the present application; Fig.15 This is a simulation result of the H-plane pattern according to an embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of this application.

[0018] It should be noted that when an element is referred to as being "fixed on" or "set on" another component, it can be directly on the other component or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0019] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0020] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0021] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.

[0022] Figure 1 - Fig.10 The embodiment of the filter power division circular polarization antenna module based on LTCC of the present application is shown, including a ceramic dielectric module 1, a filter 2, a power divider 3, a phase shifter 4, a patch antenna 5 and a quasi-coaxial transmission structure 6; the ceramic dielectric module 1 is arranged around the filter 2, the power divider 3, the phase shifter 4, the patch antenna 5 and the quasi-coaxial transmission structure 6; the filter 2 is arranged at the lower part and the middle part of the ceramic dielectric module 1, and the filter 2 includes a plurality of cascaded resonant cavities for filtering the signal. The power divider 3 and the phase shifter 4 are arranged at the upper part of the ceramic dielectric module 1, and the power divider 3 is used to distribute the power of the output signal of the filter 2. The phase shifter 4 is used to shift the phase of the output signal of the power divider 3. The patch antenna 5 is arranged on the upper surface of the ceramic dielectric module 1, and the patch antenna 5 outputs the signal through the phase shifter 4 for dual-port feeding, and radiates circularly polarized electromagnetic waves. The quasi-coaxial transmission structure 6 is arranged in the ceramic dielectric module 1, and connects the filter 2 and the power divider 3.

[0023] The present application discloses a LTCC-based filtering power-dividing circularly polarized antenna module, which superimposes multiple layers of circuits in a substrate, realizes a complex three-dimensional circuit design, and integrates passive components such as a power divider 3 and a filter 2. It meets the requirements of high frequency, large bandwidth and low power consumption. Thanks to the high temperature resistance and heat shock resistance of the ceramic substrate, it has good mechanical strength and is suitable for use in harsh environments. Compared with traditional circuit design, LTCC technology has significant miniaturization advantages, and can achieve high-density packaging and smaller circuit size. And through stripline feeding, it is easy to combine with other LTCC RF devices, and has good application potential in the satellite Internet communication wave frequency band.

[0024] In some embodiments, Figure 1 and Figure 4As shown, the stripline feeding port 11 of the antenna module is arranged on the side of the ceramic dielectric module 1 , and the stripline feeding port 11 is connected to the filter 2 through a quasi-coaxial transmission structure 6 .

[0025] In some embodiments, Figure 2 and Figure 4 As shown, the quasi-coaxial transmission structure 6 includes a quasi-coaxial inner conductor 61 and a quasi-coaxial outer wall 62. The quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62 are both made of metal. The quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62 through-holes between the first metal ground plate 21 and the second metal ground plate 22 connect the stripline feeding port 11 and the filter 2, and the quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62 through-holes arranged between the sixth metal ground plate 26 and the seventh metal ground plate 27 connect the filter 2 and the power divider 3.

[0026] The quasi-coaxial transmission structure 6 mainly serves as the input and output of the filter 2, and the input end is connected to the 50-ohm stripline feed port 11, which is on the side of the ceramic dielectric module 1, and other LTCC components are connected on the side of the ceramic dielectric module 1. The output end of the quasi-coaxial transmission structure 6 is connected to the input branch 31 of the power divider 3.

[0027] The impedance of the quasi-coaxial transmission structure 6 is adjusted by adjusting the distance between the quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62. The input and output ends of the filter 2 are matched with its connection port. The radius of the through holes of the quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62 are both R2, and the distance between adjacent through holes of the quasi-coaxial outer wall 62 is S2, which can be modified according to actual indicators and processing technology.

[0028] In this embodiment, the radius R2 of the quasi-coaxial inner conductor 61 is 0.024 mm, the height is 0.384 mm, the radius R2 of the through hole of the quasi-coaxial outer wall 62 is 0.024 mm, the height is 0.192 mm, the distance S2 between adjacent through holes of the quasi-coaxial outer wall 62 is 0.21 mm, and the distance between the quasi-coaxial inner conductor 61 and the quasi-coaxial outer wall 62 is 0.2 mm.

[0029] In some embodiments, Figure 1 - Fig. 9As shown, the filter 2 includes a first disk patch 201, a first stripline 202, a second disk patch 203, a second stripline 204 and a plurality of metal grounding plates, the plurality of metal grounding plates are stacked, and from top to bottom are the first metal grounding plate 21, the second metal grounding plate 22, the third metal grounding plate 23, the fourth metal grounding plate 24, the fifth metal grounding plate 25 and the sixth metal grounding plate 26, the first disk patch 201 is connected to the first stripline 202, the first disk patch 201 and the first stripline 202 are arranged between the second metal grounding plate 22 and the third metal grounding plate 23, the first end of the first stripline 202 is adjacent to the stripline feeding port 11 and is located at the edge of the ceramic dielectric module 1, and the second end of the first stripline 202 is located at the ceramic dielectric module 1. On the other side of the block 1, adjacent to the middle of the ceramic dielectric module 1, the first disc patch 201 is located on the upper side of the second end of the first stripline 202, the first disc patch 201 is connected to the second end of the first stripline 202 through the first connecting through hole 13 on the ceramic dielectric module 1, the first stripline 202 serves as the input end of the filter 2, the second disc patch 203 is connected to the second stripline 204, the second disc patch 203 and the second stripline 204 are arranged between the fifth metal grounding plate 25 and the sixth metal grounding plate 26, the first end of the second stripline 204 is on the same side as the first end of the first stripline 202, adjacent to the middle of the ceramic dielectric module 1, and the second end of the second stripline 204 is on the same side as the second end of the first stripline 202, adjacent to the edge of the ceramic dielectric module 1. The second disk patch 203 is located on the upper side of the second end of the second stripline 204 . The second disk patch 203 is connected to the second end of the second stripline 204 through the second connecting through hole 14 on the ceramic dielectric module 1 . The second stripline 204 serves as the output end of the filter 2 .

[0030] Between the second metal grounding plate 22 to the sixth metal grounding plate 26, a plurality of metal through holes 12 are arranged on the ceramic dielectric module 1 between adjacent metal grounding plates, and the plurality of metal through holes 12 form a resonant cavity. The metal through holes 12 are arranged in a square shape and are arranged adjacent to the edges of the metal grounding plates.

[0031] Specifically, the plurality of metal through holes 12 between the second metal ground plate 22 and the third metal ground plate 23 constitute the first resonant cavity 210, the first disk patch 201 and the first stripline 202 are located in the area enclosed by the first resonant cavity 210, the plurality of metal through holes 12 between the third metal ground plate 23 and the fourth metal ground plate 24 constitute the second resonant cavity 220, the plurality of metal through holes 12 between the fourth metal ground plate 24 and the fifth metal ground plate 25 constitute the third resonant cavity 230, and the plurality of metal through holes 12 between the fifth metal ground plate 25 and the sixth metal ground plate 26 constitute the fourth resonant cavity 240. The second disk patch 203 and the second stripline 204 are located in the area enclosed by the fourth resonant cavity 240.

[0032] The third metal grounding plate 23 is provided with a first metal window 231, which is arranged inside the metal through hole 12. The fourth metal grounding plate 24 is provided with a second metal window 241, and the fifth metal grounding plate 25 is provided with a third metal window 251. The first metal window 231 and the third metal window 251 extend in the same direction as the first stripline 202, and the second metal window 241 extends in a direction perpendicular to the first stripline 202.

[0033] The first resonant cavity 210 is coupled with the second resonant cavity 220 through the first metal window 231 and is stacked, the second resonant cavity 220 is coupled with the third resonant cavity 230 through the second metal window 241 and is stacked, and the third resonant cavity 230 is coupled with the fourth resonant cavity 240 through the third metal window 251 and is stacked. The filter 2 adopts a substrate integrated waveguide structure filter 2, and the substrate integrated waveguide filter 2 adopts a structure in which the first resonant cavity 210, the second resonant cavity 220, the third resonant cavity 230, and the fourth resonant cavity 240 are stacked. Magnetic coupling is achieved between the four resonant cavities by opening the first metal window 231, the second metal window 241, and the third metal window 251. The metal window is located at the strongest point of the magnetic field distribution to achieve magnetic coupling between adjacent layers of resonant cavities. The bandwidth and return loss of the filter 2 can be changed by adjusting the width and length of the metal window.

[0034] In some embodiments, the thickness of the metal ground plate is 0.01 mm. Figure 6 As shown, the radius of the metal through hole 12 is R1, and the distance between adjacent metal through holes 12 is S1. The size of R1 and S1 can be adjusted according to the processing technology and design indicators. In an example of this embodiment, the radius R1 of the metal through hole 12 is 0.075mm and the height is 0.384mm. Fig. 9 As shown, the distance S1 between adjacent metal vias 12 is 0.3 mm. Adjusting the lengths L1 and L2 of the first stripline 202 and the second stripline 204 can effectively improve the return loss of the filter 2 .

[0035] The signal enters the filter 2 from the first strip line 202, is fed into the first disk patch 201 through the first connecting through hole 13, and then passes through the first resonant cavity 210, the second resonant cavity 220, the third resonant cavity 230, and the fourth resonant cavity 240 in sequence, and then is output from the output port of the filter 2, passes through the quasi-coaxial transmission structure 6, enters the input branch 31 of the power divider 3, and is outputted by the power divider 3 in a one-to-two manner.

[0036] In some embodiments, Figure 4 and Fig.10As shown, the power divider 3 includes an input branch 31, an impedance converter and an isolation resistor 34. The input branch 31, the impedance converter and the isolation resistor 34 are arranged between the sixth metal grounding plate 26 and the seventh metal grounding plate 27. One end of the input branch 31 is connected to the second stripline 204 through the quasi-coaxial transmission structure 6, and the other end is connected to the impedance converter. The impedance converter includes a first impedance converter 32 and a second impedance converter 33. The first impedance converter 32 and the second impedance converter 33 are connected to the input branch 31, and the other end is connected to the phase shifter 4. The isolation resistor 34 is arranged between the ends of the first impedance converter 32 and the second impedance converter 33, and is adjacent to the phase shifter 4. The insertion loss of the power divider 3 is reduced by adopting the stripline method in the power divider 3, and the port isolation of the power divider 3 is improved by adding the isolation resistor 34.

[0037] In some embodiments, Figure 4 and Fig.10 As shown, the phase shifter 4 includes a third stripline 41 and a fourth stripline 42, which are arranged between the sixth metal ground plate 26 and the seventh metal ground plate 27, one end of the third stripline 41 is connected to the first impedance converter 32, and the other end is connected to the first metallized feed via 43, one end of the fourth stripline 42 is connected to the second impedance converter 33, and the other end is connected to the second metallized feed via 44. The first metallized feed via 43 and the second metallized feed via 44 are connected to the patch antenna 5. The two signals output by the power divider 3 pass through the phase shifter 4, so that the phase difference of the two signals is 90 degrees, and are fed into the patch antenna 5 through the first metallized feed via 43 and the second metallized feed via 44.

[0038] In some embodiments, the resistance of the first impedance converter 32 and the second impedance converter 33 is 70.7 ohms, and the resistance of the input branch 31 is 50 ohms. Figure 4 As shown, the first impedance converter 32 and the second impedance converter 33 are composed of four strip lines with lengths of P1, P2, P3, and P4 respectively. The total length reference value of the first impedance converter 32 and the second impedance converter 33 is one-quarter of the wavelength in the medium. The lengths of the four strip lines can be adjusted according to actual conditions.

[0039] In some embodiments, the isolation resistor 34 connected to the ends of the first impedance converter 32 and the second impedance converter 33 can improve the isolation between the two ports of the power divider 3. The size of the isolation resistor 34 is 0.1 mm×0.18 mm, and the resistance is 100 ohms. The size and resistance of the isolation resistor 34 can be changed according to actual conditions. The first metallized feed through hole 43 and the second metallized feed through hole 44 penetrate the ceramic dielectric module 1, and the radius is 0.06 mm.

[0040] In some embodiments, the filter 2 is a substrate integrated waveguide filter 2 of the 29 GHz - 29.9 GH frequency band, the power divider 3 is a one-to-two Wilkinson power divider 3 of the 29 GHz - 29.9 GH frequency band, the phase shifter 4 is a stripline phase shifter 4 of the 29 GHz -29.9 GH frequency band, the substrate integrated waveguide filter 2 and the Wilkinson power divider 3 are cascaded through a quasi-coaxial transmission structure 6, the phase shifter 4 is directly connected to the Wilkinson power divider 3 through a stripline, and the antenna is dual-port fed through the two outputs of the phase shifter 4.

[0041] When applied, since the impedance of the output / input ports of the filter 2 and the power divider 3 have been pre-adjusted to 50 ohms, the impedance matching of the two devices can be achieved by simply adjusting the impedance of the quasi-coaxial transmission structure 6 to 50 ohms; the output port of the power divider 3 and the input port of the phase shifter 4 are both 50-ohm strip lines, and the two can be directly connected to achieve impedance matching. The two outputs of the phase shifter 4 feed the patch antenna 5 through the metal through-hole 12, and the feeding points are distributed in the horizontal and vertical directions of the rectangular patch.

[0042] In some embodiments, the patch antenna 5 is square, and the phase shifter 4 outputs two signals with a phase difference of 90 degrees. The patch antenna 5 is fed through the first metallized feeding hole 43 and the second metallized feeding hole 44. The feeding points are distributed in the horizontal and vertical axis directions of the rectangular patch. The resonant frequency and harmonic loss of the antenna can be effectively adjusted by adjusting the position of the feeding point.

[0043] In some embodiments, the patch antenna 5 has a size of 1.8 mm×1.8 mm, a horizontal axis feeding position is 0.3 mm from the center of the patch, and a vertical axis feeding position is 0.45 mm from the center of the patch.

[0044] In this embodiment, the filter 2, the power divider 3, the phase shifter 4 and the antenna are cascaded to form a filter power divider circular polarization antenna module. By integrating multiple devices and completing the isolation and matching functions of a single device inside the module, the dependence on external isolation and matching circuits is reduced. In addition, the use of a multi-device stacking design effectively reduces the overall volume and loss of the RF equipment. Therefore, the design of a multi-device integrated module has become a key method to achieve miniaturization of the RF front end.

[0045] The ceramic dielectric module 1 includes a plurality of dielectric substrates, which are stacked; there are 28 dielectric substrates, which are the first substrate to the twenty-eighth substrate from top to bottom. The filter 2 is arranged at the third substrate to the twenty-first substrate, the power divider 3 and the phase shifter 4 are arranged at the twenty-second substrate to the twenty-third substrate, and the patch antenna 5 is arranged on the upper surface of the twenty-eighth substrate. The quasi-coaxial inner conductor 61 is arranged between the third substrate to the sixth substrate, and between the nineteenth substrate to the twenty-first substrate; the quasi-coaxial outer wall 62 is a metal through hole 12 arranged around the quasi-coaxial inner conductor 61, and the quasi-coaxial outer wall 62 is arranged between the third substrate to the fourth substrate, and between the twenty-first substrate to the twenty-second substrate. The first metal ground plane 21 is disposed between the third substrate and the fourth substrate, the second metal ground plane 22 is disposed between the fifth substrate and the sixth substrate, the third metal ground plane 23 is disposed between the ninth substrate and the tenth substrate, the fourth metal ground plane 24 is disposed between the thirteenth substrate and the fourteenth substrate, the fifth metal ground plane 25 is disposed between the seventeenth substrate and the eighteenth substrate, and the sixth metal ground plane 26 is disposed between the twenty-first substrate and the twenty-second substrate. The phase shifter 4 is disposed at the twenty-second substrate.

[0046] The first to twenty-eighth substrates are made of Ferro-A6M material with a relative dielectric constant of 5.9 and a loss tangent of 0.001. Each dielectric substrate is 0.096 mm thick and is manufactured using a low temperature co-fired ceramic process. In the ceramic dielectric module 1, the metal material is silver.

[0047] The filter 2, power divider 3, phase shifter 4 and antenna are stacked by LTCC process to realize the filtering power division circular polarization antenna module of satellite Internet communication frequency band. And it is convenient to embed it into LTCC transceiver component through strip line feeding. While ensuring the signal transmission as required, it realizes miniaturization design.

[0048] As mentioned above, the size of the LTCC-based filter power division circular polarization antenna module is 4.75 mm×3.85 mm×2.77 mm. The module is tested for performance. Fig.11 and Fig.12 As shown in the figure, the simulation results of the filter power division circular polarization antenna module are shown. The in-band standing wave of the entire filter power division module is less than 1.4, the return loss in the passband is less than -15dB, the maximum gain in the passband is 2.45dB, and the minimum gain is 1.16dB. Fig.13 - Fig.15 As shown, the axial ratio within the antenna bandwidth is less than 3dB, achieving right-hand circular polarization.

[0049] It can be seen that the present application discloses a filtering power-dividing circularly polarized antenna module based on LTCC, which superimposes multiple layers of circuits in a substrate, realizes a complex three-dimensional circuit design, and integrates passive components such as power dividers and filters. Thanks to the high temperature and heat shock resistance of the ceramic substrate, it has good mechanical strength and is suitable for use in harsh environments. Compared with traditional circuit design, LTCC technology has significant miniaturization advantages, and can achieve high-density packaging and smaller circuit size. And through stripline feeding, it is easy to combine with other LTCC RF devices, and has good application potential in the satellite Internet communication wave frequency band.

[0050] The above are merely embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structural transformations made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A filter power division circular polarization antenna module based on LTCC, characterized in that: It comprises a ceramic dielectric module, a filter, a power divider, a phase shifter, a patch antenna and a quasi-coaxial transmission structure; the ceramic dielectric module is arranged around the filter, the power divider, the phase shifter, the patch antenna and the quasi-coaxial transmission structure; the filter is connected to the power divider, the power divider is connected to the phase shifter, and the phase shifter is connected to the patch antenna; The filter is arranged at the lower part and the middle part of the ceramic dielectric module, and the filter comprises a plurality of cascaded resonant cavities for filtering the signal; The power divider and the phase shifter are arranged on the upper part of the ceramic dielectric module, the power divider is used to distribute the power of the output signal of the filter, and the phase shifter is used to shift the phase of the output signal of the power divider; The patch antenna is arranged on the upper surface of the ceramic dielectric module, and the patch antenna is dual-port fed through the output signal of the phase shifter to radiate circularly polarized electromagnetic waves; The quasi-coaxial transmission structure is arranged in the ceramic dielectric module and is connected to the filter and the power divider.

2. The LTCC-based filtering power division circularly polarized antenna module according to claim 1, characterized in that: The antenna module further comprises a stripline feeding port, which is arranged on a side of the ceramic dielectric module and connected to the filter through the quasi-coaxial transmission structure.

3. The LTCC-based filtering power division circularly polarized antenna module according to claim 2, characterized in that: The filter comprises a first disc patch, a first stripline, a second disc patch, a second stripline and a plurality of metal grounding plates, wherein the plurality of metal grounding plates are stacked and arranged, and are the first metal grounding plate, the second metal grounding plate, the third metal grounding plate, the fourth metal grounding plate, the fifth metal grounding plate and the sixth metal grounding plate from top to bottom, wherein the first disc patch is connected to the first stripline, and the first disc patch and the first stripline are arranged between the second metal grounding plate and the third metal grounding plate, wherein the first end of the first stripline is adjacent to the stripline feeding port and is located at the edge of the ceramic dielectric module, and the second end of the first stripline is located at the other side of the ceramic dielectric module and is adjacent to the middle of the ceramic dielectric module; the first disc patch is located at the upper side of the second end of the first stripline, and the first disc patch is connected to the second end of the first stripline through a first connecting through hole on the ceramic dielectric module, and the first stripline serves as the input end of the filter; The second circular disc patch is connected to the second stripline, and the second circular disc patch and the second stripline are arranged between the fifth metal ground plate and the sixth metal ground plate. The first end of the second stripline is on the same side as the first end of the first stripline, adjacent to the middle of the ceramic dielectric module, and the second end of the second stripline is on the same side as the second end of the first stripline, adjacent to the edge of the ceramic dielectric module; the second circular disc patch is located on the upper side of the second end of the second stripline, and the second circular disc patch is connected to the second end of the second stripline through a second connecting through hole on the ceramic dielectric module, and the second stripline serves as the output end of the filter.

4. The LTCC-based filtering power division circularly polarized antenna module according to claim 3, characterized in that: A plurality of metal through holes are provided on the ceramic dielectric module between the second metal grounding plate to the sixth metal grounding plate and between adjacent metal grounding plates, and the plurality of metal through holes constitute the resonant cavity; the plurality of metal through holes between the second metal grounding plate and the third metal grounding plate constitute the first resonant cavity, the first disk patch and the first strip line are located in the area enclosed by the first resonant cavity, the plurality of metal through holes between the third metal grounding plate and the fourth metal grounding plate constitute the second resonant cavity, the plurality of metal through holes between the fourth metal grounding plate and the fifth metal grounding plate constitute the third resonant cavity, the plurality of metal through holes between the fifth metal grounding plate and the sixth metal grounding plate constitute the fourth resonant cavity, and the second disk patch and the second strip line are located in the area enclosed by the fourth resonant cavity; The third metal grounding plate is provided with a first metal window, the fourth metal grounding plate is provided with a second metal window, and the fifth metal grounding plate is provided with a third metal window; the first metal window and the third metal window have the same extension direction as the first stripline, and the extension direction of the second metal window is perpendicular to the extension direction of the first stripline; The first resonant cavity is coupled to the second resonant cavity through the first metal window, the second resonant cavity is coupled to the third resonant cavity through the second metal window, and the third resonant cavity is coupled to the fourth resonant cavity through the third metal window.

5. The LTCC-based filtering power division circularly polarized antenna module according to claim 4, characterized in that: The metal grounding plate also includes a seventh metal grounding plate, and the seventh metal grounding plate is arranged on the upper side of the sixth metal grounding plate. The quasi-coaxial transmission structure includes a quasi-coaxial inner conductor and a quasi-coaxial outer wall. The quasi-coaxial inner conductor and the quasi-coaxial outer wall through holes between the first metal grounding plate and the second metal grounding plate connect the stripline feeding port and the filter. The quasi-coaxial inner conductor and the quasi-coaxial outer wall through holes arranged between the sixth metal grounding plate and the seventh metal grounding plate connect the filter and the power divider.

6. The LTCC-based filtering power division circularly polarized antenna module according to claim 5, characterized in that: The power divider includes an input branch, an impedance converter and an isolation resistor, wherein the input branch, the impedance converter and the isolation resistor are arranged between the sixth metal ground plate and the seventh metal ground plate, wherein one end of the input branch is connected to the second strip line through the quasi-coaxial transmission structure, and the other end is connected to the impedance converter; the impedance converter includes a first impedance converter and a second impedance converter, wherein the first impedance converter and the second impedance converter are connected to the input branch, and the other end is connected to the phase shifter; the isolation resistor is arranged between the ends of the first impedance converter and the second impedance converter, and is adjacent to the phase shifter.

7. The LTCC-based filtering power division circularly polarized antenna module according to claim 6, characterized in that: A first metallized feed through hole and a second metallized feed through hole are arranged on the upper part of the ceramic dielectric module. The phase shifter includes a third stripline and a fourth stripline, and the third stripline and the fourth stripline are arranged between the sixth metal ground plate and the seventh metal ground plate. One end of the third stripline is connected to the first impedance transformer, and the other end is connected to the first metallized feed through hole. One end of the fourth stripline is connected to the second impedance transformer, and the other end is connected to the second metallized feed through hole. The first metallized feed through hole and the second metallized feed through hole are connected to the patch antenna.

8. The LTCC-based filtering power division circularly polarized antenna module according to claim 7, characterized in that: The patch antenna is square in shape, and the phase shifter outputs two signals with a phase difference of 90 degrees, which are fed to the patch antenna through the first metallized feeding through hole and the second metallized feeding through hole.

9. The LTCC-based filtering power division circularly polarized antenna module according to claim 8, characterized in that: The ceramic dielectric module includes a plurality of dielectric substrates, which are stacked; there are 28 dielectric substrates, which are the first substrate to the twenty-eighth substrate from top to bottom, the filter is arranged at the third substrate to the twenty-first substrate, the power divider and the phase shifter are arranged at the twenty-second substrate to the twenty-third substrate, and the patch antenna is arranged on the upper surface of the twenty-eighth substrate; The first metal ground plate is arranged between the third substrate and the fourth substrate, the second metal ground plate is arranged between the fifth substrate and the sixth substrate, the third metal ground plate is arranged between the ninth substrate and the tenth substrate, the fourth metal ground plate is arranged between the thirteenth substrate and the fourteenth substrate, the fifth metal ground plate is arranged between the seventeenth substrate and the eighteenth substrate, and the sixth metal ground plate is arranged between the twenty-first substrate and the twenty-second substrate.

10. The LTCC-based filtering power division circularly polarized antenna module according to claim 9, characterized in that: The first substrate to the twenty-eighth substrate are all made of Ferro-A6M material with a relative dielectric constant of 5.9 and a loss tangent value of 0.

001. The thickness of each dielectric substrate is 0.096 mm and they are manufactured using a low-temperature co-fired ceramic process. The radius R2 of the quasi-coaxial inner conductor is 0.024 mm, and the height is 0.384 mm. The radius R2 of the quasi-coaxial outer wall through hole is 0.024 mm, and the height is 0.192 mm. The distance S2 between adjacent quasi-coaxial outer wall through holes is 0.21 mm. The distance between the quasi-coaxial inner conductor and the quasi-coaxial outer wall is 0.2 mm. The thickness of the metal grounding plate is 0.01 mm; the radius R1 of the metal through hole is 0.075 mm, the height is 0.384 mm, and the distance between adjacent metal through holes is 0.3 mm; The size of the isolation resistor is 0.1 mm×0.18 mm, the resistance is 100 ohms, and the radius of the first metallized feed through hole and the second metallized feed through hole is 0.06 mm; The patch antenna has a size of 1.8 mm×1.8 mm, a horizontal axis feeding position is 0.3 mm from the center of the patch antenna, and a vertical axis feeding position is 0.45 mm from the center of the patch antenna.

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