Broadband and low-insertion-loss millimeter wave reconfigurable reflection unit based on HTCC technology

Abstract

The invention belongs to the technical field of broadband antennas, and particularly relates to a broadband and low-insertion-loss millimeter wave reconfigurable reflection unit based on an HTCC technology. The HTCC multi-layer wiring ceramic tube shell comprises an HTCC multi-layer wiring ceramic tube shell, a unit metal circuit sheet is installed in the HTCC multi-layer wiring ceramic tube shell, the unit metal circuit sheet is connected with a plurality of pin switching diodes, a direct current control branch knot is arranged in the tube shell, the other end of the direct current control branch knot penetrates out of a cavity of the HTCC multi-layer wiring ceramic tube shell, and the other end of the direct current control branch knot is connected with the pin switching diodes. A round pad for welding a ball grid array (BGA) ball is formed at the bottom of the HTCC multilayer wiring ceramic tube shell, the tube shell is further provided with a plurality of quartz plane spiral inductors, the quartz plane spiral inductors are respectively connected with unit metal circuit sheets and direct current control branches through gold wires, an opening of the tube shell is connected with a metal cover plate, and the metal cover plate is connected with a metal wire. And a metal short circuit column is connected between the center of the unit metal circuit sheet and the metal cover plate. The invention provides a broadband and low-insertion-loss millimeter wave reconfigurable reflection unit based on an HTCC technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of broadband antennas, and in particular relates to a broadband, low insertion loss millimeter wave reconfigurable reflection unit based on HTCC technology. Background Art

[0002] Traditional phased array systems have complex architectures, high flexibility, high aperture efficiency, and two-dimensional beam scanning capabilities, but are usually expensive. Traditional parabolic reflector antenna systems are simple, have high gain, wide bandwidth, but have fixed beams, and are usually low cost. Reconfigurable reflector arrays combine the traditional phased array's high-angle beam scanning capabilities with the parabolic reflector's simple air-feed method, becoming one of today's low-cost solutions for high-gain, high-angle beam scanning antennas.

[0003] In engineering practice, the popularity of reconfigurable reflectarray is far less than that of phased array and parabolic reflector antenna, mainly because of its low aperture efficiency and narrow working frequency band. The aperture efficiency of reconfigurable reflectarray is mainly determined by the efficiency of feed source, illumination efficiency, feed source shielding and unit insertion loss. Among them, the efficiency of feed source, illumination efficiency, feed source shielding and other factors are determined when the empty feed architecture is selected. The selection principle is the same as that of traditional parabolic reflector antenna, and the limit efficiency is about 70%; the unit insertion loss is mainly determined by the accuracy of the reflection amplitude insertion loss and reflection phase of the reconfigurable reflector unit. The working bandwidth of the reconfigurable reflectarray mainly depends on the working bandwidth of the feed source and the bandwidth of the reflector unit. In order to pursue high efficiency, horn antennas are usually selected as feed sources, and their working frequency band can be at least 3:1. Therefore, the main factor restricting the bandwidth of the reconfigurable reflectarray is the bandwidth of the reflector unit. When the empty feed architecture is determined, improving the reflection amplitude and reflection phase performance of the unit in a wide frequency band can effectively improve the aperture efficiency and working bandwidth of the reconfigurable reflectarray.

[0004] Xidian University disclosed a broadband beam scanning reflectarray antenna based on a multi-resonance frequency reconfigurable reflector unit in its patent application “A broadband beam scanning reflectarray antenna” (application number 202011411499.7, publication number CN 113113774A). The unit includes a double layer of patches with similar shapes but different resonant frequencies, which are connected to a pin diode in series and then grounded, and a 180° reflection phase difference is formed by controlling the on and off states of the pin diode. The 180°±20° phase bandwidth is approximately 24.5%. The reflection amplitude insertion loss of the unit is less than 0.65dB, which can effectively improve the aperture efficiency after the array, but due to the 1-bit phase resolution, an additional quantization insertion loss of about 3dB is brought about.

[0005] In the article “A 2-bit Circularly Polarized Reconfigurable Reflectarray Using Pin Diode Tuned Crossed-Bowtie Patch Elements” published in IEEE TRANSACTIONS ON ANTENNA AND PROPAGATION, VOL.71, NO.9, SEPTEMBER, 2023, Fan Wu et al. proposed a 2-bit reconfigurable reflector unit based on rotation phase. The unit is composed of 8 diodes loaded with 4 groups of bowtie-shaped dipoles. Only one pair of pin diodes is selected at a time, and the others are cut off, which can achieve a 90° phase difference step, a unit bandwidth greater than 20%, and a phase difference stable at 90°±5°. The phase of the unit is extremely stable, but the unit bandwidth is slightly insufficient. At the same time, using 8 pin diodes to achieve only 2-bit phase results in a waste of cost.

[0006] In order to further improve the bandwidth of the reconfigurable reflective unit and reduce the insertion loss of the unit, the present invention proposes a millimeter wave reconfigurable unit based on the HTCC multi-layer wiring process. Through the HTCC three-dimensional wiring capability and high ceramic strength, an air medium is introduced into the unit, which effectively improves the bandwidth of the unit and reduces the insertion loss introduced by the medium. Summary of the invention

[0007] In order to solve the above problems existing in the prior art, the purpose of the present invention is to provide a broadband, low insertion loss millimeter wave reconfigurable reflection unit based on the HTCC process. Through the HTCC three-dimensional wiring capability and high ceramic strength, an air medium is introduced into the unit, which effectively improves the bandwidth of the unit while reducing the insertion loss introduced by the medium.

[0008] The technical solution adopted by the present invention is:

[0009] A broadband, low insertion loss millimeter wave reconfigurable reflection unit based on HTCC process comprises an HTCC multilayer wiring ceramic tube shell, a unit metal circuit sheet is installed in the HTCC multilayer wiring ceramic tube shell, the unit metal circuit sheet is connected to a plurality of pin switch diodes, a DC control branch is arranged in the HTCC multilayer wiring ceramic tube shell, the other end of the DC control branch passes through the cavity of the HTCC multilayer wiring ceramic tube shell, and vertically extends along the outer side of the HTCC multilayer wiring ceramic tube shell to the bottom of the HTCC multilayer wiring ceramic tube shell, a circular pad is formed at the bottom of the HTCC multilayer wiring ceramic tube shell, a BGA ball is welded to the circular pad, the HTCC multilayer wiring ceramic tube shell is also provided with a plurality of quartz planar spiral inductors, the quartz planar spiral inductors are respectively connected to the unit metal circuit sheet and the DC control branch through gold wires, the opening of the HTCC multilayer wiring ceramic tube shell is connected to a metal cover plate, the center of the unit metal circuit sheet is connected to a metal short-circuit column, and the other end of the metal short-circuit column is connected to the metal cover plate.

[0010] The HTCC multilayer wiring ceramic tube shell is a hollow structure (with a cavity inside), and the metal circuit of the reconfigurable reflection unit is printed on the inner surface of the tube shell cavity and electroplated with a gold layer. When working, the metal circuit uses the air cavity as a medium, resonates in multiple working modes, and forms a wider working frequency band. The pin switch diode is assembled on the circuit inside the cavity to control the on and off of the RF signal of the corresponding branch. The quartz plane spiral inductor is connected in series with the pin switch diode to contain the RF signal and conduct the DC control signal. The BGA solder ball is connected to the quartz plane inductor through the metal branch on the outside of the tube shell, and will be interconnected with the PCB adapter board to transfer the DC control signal. The external millimeter wave signal is sensed by the metal circuit, flows to the corresponding branch through the turned-on pin switch diode, is contained by the quartz plane spiral inductor, and the signal is reflected to form a reflected wave. The DC control signal controls the on and off state switching of the pin switch diode through the BGA solder ball and the quartz plane spiral inductor.

[0011] The present invention aims at the problem that the reconfigurable reflector array has low market acceptance due to low aperture efficiency and narrow working bandwidth, and proposes a broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC multi-layer wiring process. The present invention mainly forms a metal unit circuit and an air cavity through the HTCC multi-layer wiring process, and uses the air cavity as the medium of the unit resonance, which can expand the working bandwidth of the reconfigurable reflector unit to 34.7%, improve the phase stability to ±0.5°, reduce the unit insertion loss to 1dB, and the unit becomes a standard ceramic package device.

[0012] As a preferred solution of the present invention, a sealing ring is arranged between the metal cover plate and the opening of the HTCC multilayer wiring ceramic tube shell. The sealing ring and the metal cover plate form an airtight and watertight package for the cavity of the tube shell, so that the reconfigurable reflector unit forms a standard ceramic packaging device in terms of technology.

[0013] As a preferred solution of the present invention, the quartz planar spiral inductor is connected to the unit metal circuit sheet and the DC control branch respectively through a φ20um gold wire; the inductance value of the quartz planar spiral inductor is 5nH at 20GHz.

[0014] As a preferred solution of the present invention, the composition and weight ratio of the BGA solder ball are: 90% lead and 10% tin; the ball diameter of the BGA solder ball is 550um.

[0015] As a preferred solution of the present invention, the thickness of the metal cover plate is 20 um; the thickness of the sealing ring is 30 um.

[0016] As a preferred solution of the present invention, the material of the HTCC multi-layer wiring ceramic tube package includes 92% by weight of aluminum oxide.

[0017] As a preferred solution of the present invention, the HTCC multilayer wiring ceramic tube shell has a regular hexagonal column shape; the interior of the HTCC multilayer wiring ceramic tube shell is a cavity, the cavity is a regular hexagonal column, and three non-adjacent corners of the cavity are chamfered.

[0018] As a preferred solution of the present invention, the HTCC multilayer wiring ceramic tube shell has a side length of 7.2 mm and a height of 1.9 mm; the height of the cavity is 1.3 mm, the chamfered side length is 1.76 mm, and the thickness of the HTCC multilayer wiring ceramic tube shell is 0.85 mm.

[0019] As a preferred embodiment of the present invention, the unit metal circuit sheet includes a circular patch and three fan-shaped branches rotationally symmetrically distributed on the circular patch, each fan-shaped branch is equipped with a pin switch diode with an inverted structure, the three pin switch diodes are connected in parallel and a DC control branch is arranged between adjacent fan-shaped branches.

[0020] As a preferred embodiment of the present invention, the radius of the circular patch is 0.98 mm, the inner radius of the fan-shaped branch is 1.58 mm, the outer radius of the fan-shaped branch is 2.26 mm, and the angle of the fan-shaped branch is 75°; the angle between the fan-shaped branch and its adjacent DC control branch is 75°, the radius of the DC control branch is 0.59 mm, and the width is 0.7 mm.

[0021] The beneficial effects of the present invention are:

[0022] The present invention aims at the problem that the reconfigurable reflector array has low market acceptance due to low aperture efficiency and narrow working bandwidth, and proposes a broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC multi-layer wiring process. The present invention mainly forms a metal unit circuit and an air cavity through the HTCC multi-layer wiring process, and uses the air cavity as the medium of the unit resonance, which can expand the working bandwidth of the reconfigurable reflector unit to 34.7%, improve the phase stability to ±0.5°, reduce the unit insertion loss to 1dB, and the unit becomes a standard ceramic package device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the structure of the HTCC multilayer wiring ceramic tube shell;

[0025] Figure 3 It is a structural diagram of a unit metal circuit sheet, a pin switch diode, and a DC control branch;

[0026] Figure 4 1 is a diagram showing the simulation results of the normal main polarization reflection amplitude under three states of the present invention;

[0027] Figure 5 1 is a diagram showing simulation results of normal cross-polarization reflection amplitudes in three states of the present invention;

[0028] Figure 6 1 is a diagram showing the simulation results of the normal main polarization reflection phase in three states of the present invention;

[0029] Figure 7 It is a simulation result diagram of the normal main polarization phase shift deviation under three states of the present invention.

[0030] In the figure: 101-unit overall perspective structure; 102-unit explosion structure; 103-HTCC multilayer wiring ceramic tube shell; 104-unit metal circuit chip; 105-pin switching diode; 106-DC control branch; 107-quartz planar spiral inductor; 108-metal short-circuit column; 109-BGA solder ball; 110-metal cover; 111-sealing ring. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0033] like Figure 1 to Figure 3 As shown, the broadband, low insertion loss millimeter wave reconfigurable reflection unit based on the HTCC process of this embodiment includes an HTCC multi-layer wiring ceramic tube shell 103, a unit metal circuit sheet 104 is installed in the HTCC multi-layer wiring ceramic tube shell 103, a plurality of pin switch diodes 105 are connected to the unit metal circuit sheet 104, and a DC control branch 106 is arranged in the HTCC multi-layer wiring ceramic tube shell 103. The opening of the HTCC multi-layer wiring ceramic tube shell 103 is connected to a metal cover plate 110, the center of the unit metal circuit sheet 104 is connected to a metal short-circuit column 108, the other end of the metal short-circuit column is connected to the metal cover plate 110, and a sealing ring 111 is arranged between the metal cover plate 110 and the opening of the HTCC multi-layer wiring ceramic tube shell 103.

[0034] The unit metal circuit sheet 104, the pin switch diode 105, the quartz plane spiral inductor 107 and other parts are all located inside the cavity of the HTCC multilayer wiring ceramic tube shell 103. The DC control branch 106 passes through the ceramic wall from the cavity of the HTCC multilayer wiring ceramic tube shell 103, and extends vertically along the outer side of the ceramic wall to the bottom of the tube shell, forming a circular pad at the bottom for soldering BGA balls. The quartz plane spiral inductor 107 is connected to the unit metal circuit sheet 104 and the DC control branch 106 respectively through a φ20um gold wire connection. The quartz plane spiral inductor 107 has an inductance value of 5nH at 20GHz, and is a mature microwave device. The metal short-circuit column 108 connects the geometric center of the unit metal circuit sheet 104 with the metal cover plate 110, which serves as the DC ground of the pin switch diode 105. The BGA solder ball 109 includes 90% lead by weight and 10% tin by weight, and the ball diameter is 550um. The thickness of the metal cover plate 110 is 20um. The thickness of the sealing ring 111 is 30 um.

[0035] Figure 2 This is an enlarged view of the HTCC multilayer wiring ceramic tube shell 103 in this embodiment. The material of the HTCC multilayer wiring ceramic tube shell 103 includes 92% by weight of aluminum oxide (black porcelain). Its shape is a regular hexagonal column with a side length of c and a thickness of h1. The interior of the tube shell is a cavity, which is a chamfered regular hexagonal column with a cavity height of h2, a chamfered side length of a, and a shell thickness of b. Specific parameters are shown in Table 1.

[0036] Table 1 shows the dimension parameters of the HTCC multilayer wiring ceramic tube package 103:

[0037] a b c h1 h2 1.76mm 0.85mm 7.2mm 1.9mm 1.3mm

[0038] Figure 3 This is an enlarged view of the unit metal circuit sheet 104, the pin switch diode 105, and the DC control branch 106 in this embodiment. These three parts are symmetrically distributed with 120° rotation with point o as the origin. The unit metal circuit sheet 104 includes a circular patch with a radius of R1 and three fan-shaped branches, with an inner radius of R3, an outer radius of R2, and an angle of φ1. Each fan-shaped branch is equipped with a flip-chip pin switch diode 105. The three pin switch diodes 105 are connected in parallel and are numbered 1#, 2#, and 3# in the counterclockwise direction; the angle between the fan-shaped branch and the adjacent DC control branch 106 is φ0, and the radius of the DC control branch 106 is R5 and the width is W1. The specific values ​​of each parameter are shown in Table 2.

[0039] Table 2 shows the size parameters of the unit metal circuit sheet 104, the pin switch diode 105, and the DC control branch 106:

[0040] R1 R2 R3 R4 R5 φ0 φ1 W1 0.98mm 2.26mm 1.58mm 2.2mm 0.59mm 75° 15° 0.7mm

[0041] Figures 4 to 7 The simulation results of the broadband, low insertion loss millimeter wave reconfigurable reflector unit based on the HTCC process of this embodiment are shown in the figure. The switch code in the figure is the code of the on and off states of the three pin switch diodes 105 in the unit, where "0" represents the off state and "1" represents the on state. The coding order is 1#2#3#, for example: "010" code represents that the 2#pin switch diode 105 is in the on state, and the 1# and 3#pin switch diodes 105 are in the off state. The simulation is performed using the periodic boundary conditions of ANSYS2021, with a triangular array and an array spacing of 7.15mm. The pin switch diode 105 uses the equivalent data provided by the manufacturer; when turned on, it is equivalent to a 4.5Ω resistor; when turned off, it is equivalent to a 0.026pF capacitor.

[0042] Figure 4 : This is the normal main polarization reflection amplitude in three states of the broadband, low insertion loss millimeter-wave reconfigurable reflection unit based on the HTCC process in this embodiment. It can be seen that in the range of 15.5 to 22 GHz, the insertion loss of the main polarization reflection amplitude in three states is uniform and stable, all of which are about 1 dB. In the existing millimeter-wave reconfigurable reflection unit design, the insertion loss is low and the relative bandwidth is 34.6%.

[0043] Figure 5The normal cross-polarization reflection amplitudes in three states of the broadband, low insertion loss millimeter-wave reconfigurable reflection unit based on the HTCC process in this embodiment. It can be seen that in the range of 15.5 to 22 GHz, the cross-polarization reflection amplitudes in three states are all less than -13 dB, and the cross-polarization is good.

[0044] Figure 6 The normal main polarization reflection phase in three states of the broadband, low insertion loss millimeter-wave reconfigurable reflection unit based on the HTCC process in this embodiment can be seen. In the range of 14 to 23 GHz, the main polarization reflection phase difference in the three states is stable at 120°, achieving a good three-phase shift.

[0045] Figure 7 This is the normal main polarization phase shift deviation of the broadband, low insertion loss millimeter-wave reconfigurable reflection unit based on the HTCC process in three states in this embodiment. It can be seen that in the range of 14 to 23 GHz, the unit phase shift deviation in the three states is no more than ±0.5°, and the phase shift accuracy is good.

[0046] This embodiment demonstrates a broadband, low insertion loss millimeter wave reconfigurable reflection unit based on the HTCC process. Combining the reflection amplitude and reflection phase of the three states, it can be seen that after the present invention introduces the air dielectric resonant cavity through the HTCC multi-layer wiring process, while maintaining the unit 1dB insertion loss, the unit operating bandwidth is 34.7%, which is about 10% wider than the bandwidth of the current broadband millimeter wave reconfigurable reflection unit, and the phase shift stability is improved to within ±0.5°, which proves the effectiveness of the method proposed in the present invention.

[0047] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that fall within the scope defined by the claims of the present invention fall within the protection scope of the present invention.

Claims

1. A broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process, characterized by: The invention comprises a HTCC multi-layer wiring ceramic tube shell (103), wherein a unit metal circuit sheet (104) is installed in the HTCC multi-layer wiring ceramic tube shell (103), wherein the unit metal circuit sheet (104) is connected to a plurality of pin switch diodes (105), wherein a DC control branch (106) is arranged in the HTCC multi-layer wiring ceramic tube shell (103), wherein the other end of the DC control branch (106) passes through the cavity of the HTCC multi-layer wiring ceramic tube shell (103), and vertically extends along the outer side of the HTCC multi-layer wiring ceramic tube shell (103) to the bottom of the HTCC multi-layer wiring ceramic tube shell (103), wherein ... A circular pad is formed at the bottom of the HTCC multilayer wiring ceramic tube shell (103), and a BGA ball is welded to the circular pad. The HTCC multilayer wiring ceramic tube shell (103) is also provided with a plurality of quartz planar spiral inductors (107), and the quartz planar spiral inductors (107) are respectively connected to the unit metal circuit sheet (104) and the DC control branch (106) through gold wires. The opening of the HTCC multilayer wiring ceramic tube shell (103) is connected to a metal cover plate (110), the center of the unit metal circuit sheet (104) is connected to a metal short-circuit column (108), and the other end of the metal short-circuit column is connected to the metal cover plate (110).

2. According to claim 1, a broadband, low insertion loss millimeter wave reconfigurable reflection unit based on HTCC process, characterized in that: A sealing ring (111) is arranged between the metal cover plate (110) and the opening of the HTCC multi-layer wiring ceramic tube shell (103).

3. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 1, characterized in that: The quartz plane spiral inductor (107) is respectively connected to the unit metal circuit sheet (104) and the DC control branch (106) through a φ20um gold wire; the inductance value of the quartz plane spiral inductor (107) is 5nH at 20GHz.

4. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 1, characterized in that: The composition and weight ratio of the BGA solder ball (109) are: 90% lead and 10% tin; the ball diameter of the BGA solder ball (109) is 550 um.

5. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 2, characterized in that: The thickness of the metal cover plate (110) is 20 um; the thickness of the sealing ring (111) is 30 um.

6. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 1, characterized in that: The material of the HTCC multi-layer wiring ceramic tube package (103) includes 92% by weight of aluminum oxide.

7. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 1, characterized in that: The HTCC multilayer wiring ceramic tube shell (103) has an outer shape of a regular hexagonal column; the interior of the HTCC multilayer wiring ceramic tube shell (103) is a cavity, which is a regular hexagonal column, and three non-adjacent corners of the cavity are chamfered.

8. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 7, characterized in that: The HTCC multilayer wiring ceramic tube shell (103) has a side length of 7.2 mm and a height of 1.9 mm; the height of the cavity is 1.3 mm, the chamfered side length is 1.76 mm, and the thickness of the HTCC multilayer wiring ceramic tube shell (103) is 0.85 mm.

9. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 1, characterized in that: The unit metal circuit sheet (104) comprises a circular patch and three fan-shaped branches which are rotationally symmetrically distributed on the circular patch, each fan-shaped branch is equipped with a pin switch diode (105) of an inverted structure, the three pin switch diodes (105) are connected in parallel and share a common ground, and a DC control branch (106) is arranged between adjacent fan-shaped branches.

10. The broadband, low insertion loss millimeter wave reconfigurable reflector unit based on HTCC process according to claim 9, characterized in that: The radius of the circular patch is 0.98 mm, the inner radius of the fan-shaped branch is 1.58 mm, the outer radius of the fan-shaped branch is 2.26 mm, and the angle of the fan-shaped branch is 75°; the angle between the fan-shaped branch and the adjacent DC control branch (106) is 75°, the radius of the DC control branch (106) is 0.59 mm, and the width is 0.7 mm.

Images