Preparation method of dual-polarized packaged antenna for 5G millimeter wave terminal

Abstract

The invention relates to a preparation method of a dual-polarization packaging antenna for a 5G millimeter wave terminal, and relates to the technical field of antennas, in particular to an antenna which is composed of an upper-layer composite substrate and a lower-layer composite substrate, the upper-layer composite substrate is arranged at the upper end of the lower-layer composite substrate, the whole antenna is divided into five layers from bottom to top, namely an M1 layer, an M2 layer, an M3 layer, an M4 layer and an M5 layer, and the M1 layer, the M2 layer, the M3 layer, the M4 layer and the M5 layer are arranged on the lower-layer composite substrate. The upper-layer composite substrate is an M5 layer; the thickness of the upper layer composite substrate is 0.9 mm; the thickness of the lower-layer composite substrate is 0.6 mm, and meanwhile the length of the lower-layer composite substrate is 7 mm. The patch antennas with parasitic elements are used in the same layer to improve the bandwidth of the antenna, so that the number of layers, increased by using stacked patches, in the antenna is reduced, the antenna is excited by two feeds with opposite phases, the bandwidth is increased, feed radiation is reduced, a matched feed network is further designed, and the bandwidth is increased. And the matching network is applied to a single-layer patch antenna with parasitic elements.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal. Background Art

[0002] Some frequency bands of 5G applications will be much higher than the previous generation of communications. In other words, the wavelength will be much shorter, so the physical size of the antenna is also greatly reduced. Before designing the antenna, through research on relevant literature, considering that the size of the patch antenna is conducive to packaging integration and the antenna structure is simple, a single-layer patch antenna is selected as a solution designed for 5G communication. However, the bandwidth of using a single-layer patch antenna is usually very limited, so some bandwidth improvement technologies need to be added.

[0003] In order to increase the available spectrum, the next generation of mobile networks will also require higher operating frequencies. The higher the carrier frequency, the larger the achievable signal bandwidth and the faster the data transmission. The following methods are usually used to handle the frequency band expansion: increasing the thickness of the dielectric substrate, but if the thickness of the dielectric sheet is too large, it will excite severe surface waves on the substrate surface, thereby reducing the radiation efficiency and affecting the bandwidth. Reducing the dielectric constant of the dielectric substrate, or selecting different dielectric substrate materials, adding parasitic units, but adding parasitic units will increase the height and increase the size of the antenna, which puts higher requirements on the application environment. The radiating patch is slotted, and the current flows along the edge, the current path is lengthened, and an additional resonant loop is introduced, which usually causes a decrease in gain. Carrier aggregation, but the spectrum is also limited by lower frequencies. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings existing in the prior art and propose a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal is designed, comprising the following steps:

[0007] S1. Material selection: The antenna is composed of an upper composite substrate and a lower composite substrate. The upper composite substrate is arranged on the upper end of the lower composite substrate. The antenna is divided into five layers from bottom to top, namely, M1, M2, M3, M4 and M5 layers, and the upper composite substrate is the M5 layer;

[0008] The thickness of the upper composite substrate is 0.9 mm; the thickness of the lower composite substrate is 0.6 mm, and the length of the substrates is 7 mm.

[0009] S2. Patches and parasitic patches: a square radiating patch with corner cutting and slotting, 4 rectangular parasitic patches and 4 U-shaped parasitic patches. All patches are concentrated on the M5 layer.

[0010] S3. Differential feeding: Using this method, the antenna is excited by two feeds with opposite phases, which increases the bandwidth and reduces the feed radiation. A matching network design is used, and the matching network is applied to a single-layer patch antenna with parasitic elements to achieve the design goals of increasing bandwidth and eliminating stray inductance.

[0011] S4. Matching network: In order to overcome the bandwidth limitation, a matching feed network is designed;

[0012] The feeding network connected to port 1 through pads and probes is located in the M2 layer. The probe is made of pec material. The size of the square pad connected to it is 0.35mm*0.43mm, and the length of the probe connected to the square pad is 0.15mm.

[0013] The feeding network connected to port 2 through pads and probes is located on the M2 and M3 layers, and the probes are made of pec material; the size of the square pad located on the M2 layer is 0.35mm*0.43mm, and the length of the probe connected to it is 0.15mm;

[0014] The diameter of the two circular pads connecting the feeding network located in the M3 layer and the feeding network located in the M2 layer are both 0.21 mm, and the length of the connected probe is 0.3 mm;

[0015] The transmission line impedance of the matching network is 50Ω, and in each branch, there is a lossless half-wavelength transmission line connected between the two corresponding balanced ports. This design enables the required 180° phase to be obtained, further ensuring that the antenna is fed by differential feeding technology;

[0016] S5. Aperture grid structure: A hole grid structure is added between the M4 and M5 layers, and the positions of the four sides are all 0.175mm away from the edge of the antenna;

[0017] The hole grid material is made of pec, and the distance between the two adjacent cylinders is 0.265mm.

[0018] Preferably, the dielectric constant of the upper composite substrate is 3.48, the dielectric constant of the lower composite substrate is 3.35, and the loss factors of the two dielectric materials are both 0.004.

[0019] Preferably, the two feeding ports and GND are on the M1 layer, and the feeding port is tangent to GND, which is convenient for antenna and chip packaging.

[0020] Preferably, M2 to M4 are the layers where the matching network is located, and a hole-grid structure is added between the M4 layer and the M5 layer.

[0021] Preferably, in step S2, the four U-shaped parasitic patches are rotationally symmetrical through the square patch located in the center, the boundary distances between the four U-shaped parasitic patches and the square patch are all 0.1 mm, and the centers of the square patch and the parasitic patch are on the same line;

[0022] Another four rectangular parasitic patches are located at the border of the antenna to form a square frame, and the size of the patch is: 7mm long and 0.5mm wide.

[0023] Preferably, in step S4, the diameters of the two circular pads are both 0.28 mm, and the length of the probe connected to the two circular pads is 1.35 mm.

[0024] Preferably, in the step S4, the diameter of the other two circular pads of the M3 layer feeding network is 0.28 mm, and the length of the connected probes is 1.35 mm.

[0025] Preferably, the model of the upper composite substrate is Rogers RO4350B, and the model of the lower composite substrate is Rogers RO4450T.

[0026] Preferably, the rectangular patch slotting is a method for increasing bandwidth. The slotting changes the path of the current, so that the current path that reaches half the wavelength at a specific frequency is reduced, the number of half-wave oscillators is reduced, and thus the gain is reduced.

[0027] Preferably, the bandwidth is increased. Although the slots may reduce the radiation efficiency, adding a hole grid structure to the antenna can reduce the effect of the slots on the radiation efficiency.

[0028] The present invention proposes a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal, which has the beneficial effects of: using a patch antenna with a parasitic element in the same layer to increase its bandwidth, thereby reducing the number of layers in the antenna increased by using stacked patches.

[0029] The design of the patch antenna with parasitic elements on the same layer makes the antenna have a larger bandwidth, but the increased bandwidth is not enough to cover the 5G millimeter wave frequency band. Differential feeding technology is used. The antenna is excited by two feeds with opposite phases, which increases the bandwidth and reduces the feed radiation. A matching feed network is also designed and applied to the single-layer patch antenna with parasitic elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1A side stacking diagram of antennas in a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0031] Figure 2 A schematic diagram of an antenna patch for a method of preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0032] Figure 3 A schematic diagram of antenna port feeding for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0033] Figure 4 The present invention provides a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal and setting the antenna port phase.

[0034] Figure 5 The invention discloses a matching feeding network for an antenna in a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal.

[0035] Figure 6 This is a simulation result change diagram of S11 of a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0036] Figure 7 This is a simulation result change diagram of S22 of a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0037] Figure 8 A hole grid structure diagram of a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0038] Fig. 9 This is a diagram of the S11 simulation results of RO4350-6.09mm and RO4450-4mm for a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0039] Fig.10 This is a diagram of the S11 simulation results of RO4350-5.08mm and RO4450-3mm for a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0040] Fig.11 This is a diagram of the S11-S22 simulation results of RO4350-3.045mm and RO4450-2mm for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0041] Fig.12A diagram of an antenna patch without corner cutting and slotting for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0042] Fig.13 This is a diagram of S11-S22 simulation results without corner cutting and slotting for a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0043] Fig.14 The antenna patch of the preparation method of a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed by the present invention has a cutting angle and a slotting diagram.

[0044] Fig.15 This is a diagram of the S11-S22 simulation results of the cutting angle and the slotting of the preparation method of the dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0045] Fig.16 The parasitic patch of the antenna of the method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed by the present invention is a U-shaped graph.

[0046] Fig.17 This is a diagram of the S11-S22 simulation results of a U-shaped parasitic patch in a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0047] Fig.18 This is a graph showing changes in S11 simulation results for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0048] Fig.19 This is a diagram of the changes in S22 simulation results of a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0049] Fig. 20 An antenna parasitic patch diagram for a method of preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0050] Fig.21 This is a diagram of the simulation results of the parasitic patches S11-S22 of the method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0051] Fig. 22 The antenna of the preparation method of a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed by the present invention has a parasitic patch diagram.

[0052] Fig.23 A simulation result diagram of parasitic patches S11-S22 for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0053] Fig.24 A diagram of an antenna hole-free grid structure for a method of preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0054] Fig.25 A gain diagram of an antenna without a hole grid in a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0055] Fig.26 A diagram of the antenna hole grid structure of a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0056] Fig. 27 A gain diagram of an antenna aperture grid in a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0057] Fig.28 This is an overall antenna effect diagram of a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0058] Fig.29 This is a diagram of the S11-S22 simulation results of the overall antenna of a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0059] Fig.30 The E-plane radiation pattern of the antenna of the method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0060] Fig.31 A graph showing how the E-plane 0° peak gain of an antenna varies with frequency in a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0061] Fig.32 A 3D directional diagram of the antenna gain of a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0062] Fig.33 A top view of a CQFN48 ceramic housing for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0063] Fig.34 A top view of a packaged antenna according to a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0064] Fig.35 The right view of the packaged antenna of the method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0065] Fig.36 A front view of a packaged antenna for a method of preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0066] Fig.37 This is an overall packaged antenna effect diagram of a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0067] Fig.38 This is a diagram of the S11-S22 simulation results of a packaged antenna for a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0068] Fig.39 This is a diagram of the S21 simulation results of a packaged antenna for a method of preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0069] Fig.40 A center frequency gain diagram of the E-plane operation of a packaged antenna according to a method for preparing a dual-polarized packaged antenna for a 5G millimeter wave terminal proposed in the present invention.

[0070] Fig.41 A 3D gain diagram of the antenna after packaging in a method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal proposed in the present invention. DETAILED DESCRIPTION

[0071] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0072] A method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal comprises the following steps:

[0073] S1. Material selection: refer to Figure 1 The antenna is composed of an upper composite substrate and a lower composite substrate. The upper composite substrate is arranged on the upper end of the lower composite substrate. The antenna is divided into five layers from bottom to top, namely, M1, M2, M3, M4 and M5 layers, and the upper composite substrate is the M5 layer;

[0074] The two feeding ports and GND are on the M1 layer, and the feeding port is tangent to GND, which is convenient for antenna and chip packaging.

[0075] M2 to M4 are the layers where the matching network is located, and a hole grid structure is added between the M4 layer and the M5 layer.

[0076] The dielectric constant of the upper composite substrate is 3.48, the dielectric constant of the lower composite substrate is 3.35, and the loss factors of the two dielectric materials are both 0.004; the model of the upper composite substrate is Rogers RO4350B, and the model of the lower composite substrate is Rogers RO4450T.

[0077] The thickness of the upper composite substrate is 0.9 mm; the thickness of the lower composite substrate is 0.6 mm, and the length of the substrates is 7 mm.

[0078] S2. Patches and parasitic patches: refer to Figure 2 , a square radiation patch with corner cutting and slotting, 4 rectangular parasitic patches and 4 U-shaped parasitic patches. All patches are concentrated on the M5 layer, reducing the antenna stacking and achieving the purpose of simplifying the antenna;

[0079] Considering the equivalent transmission line model of the patch antenna, it is regarded as a half-wave microstrip resonator, such as Figure 4 As shown, at a given substrate height h and dielectric constant ε r The antenna size for a specific design frequency can be calculated.

[0080]

[0081] Where f0 is the desired resonant frequency. The parameters u0 and ε0 represent the magnetic permeability and dielectric constant of a vacuum. Since the microstrip line is wide enough to radiate and the substrate is thin enough to eliminate substrate modes and surface waves, its width can be calculated as:

[0082]

[0083] H represents the thickness of the antenna, and W represents the length of the antenna. Therefore, the size of the square patch is 2.75mm, located in the center of the antenna, and the distance from the four edges of the antenna is 2.125mm. The sizes of the four U-shaped parasitic patches are: 1.375mm long and 0.6875 wide. The groove in the middle is 0.8mm long and 0.36mm wide.

[0084] The four U-shaped parasitic patches are rotationally symmetric through the square patch located in the center, the boundary distances between the four U-shaped parasitic patches and the square patch are all 0.1 mm, and the centers of the square patch and the parasitic patch are on the same line.

[0085] Another four rectangular parasitic patches are located at the border of the antenna to form a square frame, and the size of the patch is: 7mm long and 0.5mm wide.

[0086] Such a patch position makes it possible to reduce the parasitic effect of adding parasitic patches, which affects the radiation gain of the antenna. Rotationally symmetric patches with parasitic effects are a more effective solution to overcome the bandwidth limitation of the antenna.

[0087] S3. Differential feeding: In the design of antenna feeding methods, coaxial feeding has a simple structure, small feeder radiation loss, and can achieve impedance matching by selecting the feeding point position, but the resulting antenna bandwidth is too narrow; slot coupling feeding is flexible and has good shielding performance. Different slot shapes have different effects on coupling strength. H-type slots can obtain greater coupling than rectangular slots at the same size. The longer the slot length, the stronger the antenna coupling and the wider the bandwidth. It also leads to enhanced back radiation of the antenna, which affects the radiation gain and radiation efficiency. In addition, slot coupling feeding requires a higher number of layers, which increases the manufacturing cost.

[0088] If a microstrip line and a probe are used to feed the patch, stray inductance will be generated due to the discontinuity of the microstrip line and the length of the probe. In order to compensate for the stray inductance in the probe feeding;

[0089] Using differential feeding, the antenna is excited by two feeds with opposite phases, which increases the bandwidth and reduces the feed radiation. A matching network design is used, and the matching network is applied to a single-layer patch antenna with parasitic elements to achieve the design goals of increasing bandwidth and eliminating stray inductance. Figure 3 , the vertical polarization current is fed into port 1, the horizontal polarization current is fed into port 2, and then the two ports are set to have a phase difference of 180°;

[0090] refer to Figure 4 ,Because this design needs to be packaged with the chip, a microstrip line is needed between the chip and the antenna for ,interconnection. The chip is placed at the bottom of the antenna. ,Using this packaging solution has the least impact on the chip reception and ,transmission. Therefore, the two feeding ports of the antenna are also placed at the bottom of the antenna for ,convenient interconnection with the chip.

[0091] Differential feeding makes the antenna structure simple and easy to miniaturize. It can be directly integrated with the differential RF front end, making it easy to realize the integrated design of packaged antenna. By using differential feeding technology, the radiation characteristics of the antenna are further improved and the antenna bandwidth is increased.

[0092] S4. Matching network: In order to overcome the bandwidth limitation, a matching feed network is designed;

[0093] The feeding network connected to port 1 through pads and probes is located in the M2 layer. The probe is made of pec material. The size of the square pad connected to it is 0.35mm*0.43mm, and the length of the probe connected to the square pad is 0.15mm; the diameters of the two circular pads are both 0.28mm, and the length of the probe connected to the two circular pads is 1.35mm.

[0094] The other two circular pads of the M3 layer feeding network have a diameter of 0.28 mm and a connected probe length of 1.35 mm.

[0095] The feeding network connected to port 2 through pads and probes is located on the M2 and M3 layers, and the probes are made of pec material; the square pad located on the M2 layer is 0.35mm*0.43mm in size, and the probe connected to it is 0.15mm long; the diameters of the two circular pads connected to the feeding network located on the M3 layer and the feeding network located on the M2 layer are both 0.21mm, and the length of the connected probes is 0.3mm;

[0096] The transmission line impedance of the matching network is 50Ω, and in each branch, there is a lossless half-wavelength transmission line connected between two corresponding balanced ports. This design enables the required 180° phase to be obtained, further ensuring that the antenna is fed by differential feeding technology. By applying the matching network to a single-layer patch antenna with parasitic elements, a wider bandwidth can be obtained, and the number of layers of the antenna is reduced, thereby reducing the manufacturing cost of the antenna.

[0097] refer to Figure 5 The yellow part in the matching feed network is the adjustable part, and the bandwidth of the antenna can be changed by adjusting its length.

[0098] like Figure 6 As shown, through Figure 6 From the trend of the S11 simulation results, we can see that the absolute bandwidth of the antenna increases with the increase of length, and as the length increases, the increase in bandwidth also increases, and the return loss of the antenna is getting better and better. Therefore, through the comparative analysis of the simulation results, it is concluded that the absolute bandwidth of antenna port 1 increases with the increase of the length of the yellow part in the feed network, and in order to obtain a relative bandwidth that matches the design goal, the length should be at least 0.6mm.

[0099] like Figure 7 As shown, through Figure 7From the trend of the S22 simulation results, we can see that the absolute bandwidth of the antenna increases with the increase of length, and as the length increases, the increase in bandwidth also increases, and the return loss of the antenna is getting better and better. Therefore, through the comparative analysis of the simulation results, it is concluded that the absolute bandwidth of antenna port 2 increases with the increase of the length of the yellow part in the feed network, and in order to obtain a relative bandwidth that matches the design goal, the length should be at least 0.6mm.

[0100] S5. Aperture grid structure: Figure 8 As shown, between the M4 layer and the M5 layer, a hole grid structure is added, and the positions of the four sides are all 0.175mm away from the edge of the antenna;

[0101] The hole grid material is made of pec, and the distance between the two adjacent cylinders is 0.265mm.

[0102] The performance of the antenna is greatly affected by the dielectric constant of the dielectric substrate. Because the dielectric constant of ordinary dielectric materials is generally lower than that of ceramic dielectric materials, the Q value will be increased when it is designed as a dielectric substrate, thereby greatly increasing the size of the substrate. As one of the metamaterials, the left-handed medium has the characteristics of negative dielectric constant and magnetic permeability. When used in antenna design, the antenna volume is smaller than that of general materials under the same performance. Low-temperature co-fired ceramic (LTCC) technology has a wide range of applications in communication systems due to its good high-frequency characteristics, low dielectric loss, high thermal conductivity, and multi-layer structure. However, compared with traditional dielectric materials, the prices of special materials such as ceramics or left-handed media are relatively high, which will lead to an increase in the cost of the designed antenna and make it impossible to mass-produce it at low cost.

[0103] The dielectric substrates selected for this antenna design are Rogers' RO4350B and RO4450T.

[0104] Rogers RO4350B material is designed for high volume, high performance commercial applications. It offers high coverage and low loss.

[0105] The two materials are stacked to form the dielectric substrate of the antenna, with the upper layer being RO4350 and the lower layer being RO4450, which enables the antenna to have low cost, moderate dielectric constant and low loss factor. At the same time, both materials can be purchased on the market, providing convenience, reliability and speed for the actual production of antennas for testing.

[0106] The equivalent dielectric constant is related to the dielectric thickness, refer to Fig. 9Through the simulation results, we can get that the bandwidth of the antenna is too low, the curve fluctuates a lot, and the amplitude is large. When the thickness increases, the resonant frequency generally moves to a low frequency, and when it decreases, it moves to a high frequency. Therefore, the choice of dielectric material thickness has a great influence on the antenna operating frequency and bandwidth, and how to choose the appropriate dielectric material thickness is also a problem that needs to be solved.

[0107] refer to Fig.10 ,Through the simulation results, we can get that the bandwidth of the antenna has increased, but there is still a ,protrusion, and the return loss is not good.

[0108] refer to Fig.11 , simulate S11-S22 of RO4350-3.045mm and RO4450-2mm.

[0109] Through the above Figure 9-11 From the three simulation result graphs, we can see that when the thickness of the dielectric material is too large, the S parameter curve of the antenna simulation shows a low bandwidth and too many curve protrusions. When the total thickness decreases, the antenna operating frequency and antenna bandwidth increase. When RO4450 is selected as 2mm, the S11 and S22 parameter curves in the simulation results are relatively smooth and have no protrusions. And the bandwidth is 3.43GHz-4.72GHz. Through the above three comparative experiments, we can know that when ROS4350 and ROS4450 are used together, the lower the thickness of the dielectric material, the larger the bandwidth. Finally, according to the design target requirements and the characteristics of the dielectric material experimental comparison, the total thickness of the dielectric material required for the antenna is 1.5mm, ROS4350 is 0.69mm, and ROS4450 is 0.6mm.

[0110] In order to increase the bandwidth of the antenna, a comparative experiment was designed to perform slotting and corner cutting on the patch antenna during the experiment. Whether the rectangular patch has corner cutting has a certain influence on the bandwidth of the antenna. Slotting in the rectangular patch is a method that can increase the bandwidth. Slotting changes the path of the current, which reduces the current path that reaches half the wavelength at a specific frequency, and the number of half-wave oscillators is reduced, so the gain is reduced.

[0111] The bandwidth is increased. Although the slots will reduce the radiation efficiency, adding a hole grid structure to the antenna can reduce the impact of the slots on the radiation efficiency.

[0112] The radiation patch of the antenna has no cut corners or slots. Through HFSS simulation analysis, the S11-S22 parameters of the antenna are obtained as shown in Figure 12.

[0113] Depend on Fig.13As shown in the simulation results, it can be clearly seen that the bandwidth range of antenna port 2 without cutting corners and slots is from 22.11GHz to 23.44GHz, the absolute bandwidth is only 1.33GHz, and the relative bandwidth is only 5.3%; while the bandwidth range of antenna port 1 is from 23.78GHz to 25.04GHz, the absolute bandwidth is only 1.26GHz, and the relative bandwidth is only 5.1%.

[0114] The antenna's radiation patch has cut corners and slots. Through HFSS simulation analysis, the antenna's S11-S22 parameters are obtained as follows: Fig.14 shown.

[0115] Depend on Fig.15 As shown in the figure, through the simulation results, it can be clearly seen that the antenna bandwidth of the patch with angle cutting and slotting has increased, and the relative bandwidth has also increased. The bandwidth range of antenna port 1 is from 22.32GHz-23.46GHz, 24.7GHz-25GHz, the absolute bandwidth is 1.44GHz in total, and the relative bandwidth is 5.8%; the bandwidth range of antenna port 2 is from 23.1GHz-24.3GHz, 24.9GHz-26.2GHz, the absolute bandwidth is 2.6GHz in total, and the relative bandwidth is 10.1%. Therefore, by comparing the angle cutting and slotting of the antenna patch, the analysis results show that the relative bandwidth of the antenna can be effectively increased by cutting and slotting the antenna radiation patch.

[0116] Depend on Fig.16 As shown, the parasitic patch of the antenna is U-shaped, and the S11-S22 of the antenna is obtained by simulation analysis through HFSS.

[0117] Depend on Fig.17 As shown in the figure, through the simulation results, it can be clearly seen that when the parasitic patch of the antenna is changed from a rectangular parasitic patch to a U-shaped parasitic patch, the S11 and S22 curves of the antenna have a significant decrease. Therefore, by comparing the simulation results, it can be concluded that the U-shaped parasitic patch is more effective in increasing the absolute bandwidth of the antenna than the rectangular parasitic patch, and after using the U-shaped parasitic patch, the antenna has a better return loss.

[0118] Depend on Fig.18 As shown in the figure, through the simulation results, it can be clearly seen that when the antenna patch is slotted and cut, and the parasitic patch is changed from a rectangular parasitic patch to a U-shaped parasitic patch, the overall S11 curve of the antenna has a significant decrease. Therefore, by comparing the simulation results, it can be concluded that slotting and cutting the antenna patch and using a U-shaped parasitic patch are more effective in increasing the absolute bandwidth of the antenna, and after using the U-shaped parasitic patch, the antenna has a better callback loss.

[0119] Depend on Fig.19As shown in the figure, through the simulation results, it can be clearly seen that when the antenna patch is slotted and cut, and the parasitic patch is changed from a rectangular parasitic patch to a U-shaped parasitic patch, the absolute bandwidth of the antenna S22 simulation result has a significant increase. Therefore, by comparing the simulation results, it can be concluded that slotting and cutting the antenna patch and using a U-shaped parasitic patch are more effective in increasing the absolute bandwidth of the antenna.

[0120] Comparative analysis of the presence and absence of parasitic patches: In addition to the thickness and dielectric constant of the dielectric substrate, some minor differences that affect the antenna bandwidth also have a great impact on the antenna bandwidth, such as the position and impedance of the matching network. There are many ways to increase the antenna bandwidth. In addition to the method of cutting corners and slotting patches mentioned in 3.2, there is another method, which is to add parasitic units.

[0121] Eight parasitic patches are added outside the main radiation patch. Four U-shaped parasitic patches are rotationally symmetrical through the square patch in the center, and the other four are located at the antenna boundary to form a square frame. The matching network is applied to a single-layer patch antenna with parasitic patches. Through comparative simulation experiments, it is proved that the bandwidth of the antenna can be increased. Fig. 20 As shown, the antenna has no parasitic patch, and the S11-S22 parameters of the antenna are obtained through HFSS simulation analysis.

[0122] Depend on Fig.21 As shown, through the simulation results, it can be clearly seen that the bandwidth range of antenna port 2 without parasitic patch is from 22.7GHz to 24.2GHz, the absolute bandwidth is only 1.5GHz, and the relative bandwidth is only 6.1%; while the bandwidth range of antenna port 1 is from 22.7GHz to 24.8GHz, the absolute bandwidth is only 2.1GHz, and the relative bandwidth is only 8.5%.

[0123] like Fig. 22 As shown in the figure, the antenna's radiation patch has cut corners and slots. Through HFSS simulation analysis, the antenna's S11-S22 parameters are obtained.

[0124] Depend on Fig.23 As shown in the figure, through the simulation results, it can be clearly seen that the bandwidth range of antenna port 2 without parasitic patches is from 22.9GHz to 25.9GHz, the absolute bandwidth is only 3GHz, and the relative bandwidth is 12.2%; while the bandwidth range of antenna port 1 is from 23.1GHz to 26.1GHz, the absolute bandwidth is 3GHz, and the relative bandwidth is 12.2%. Compared with the simulation results without parasitic patches, the absolute bandwidth S11 of the antenna increased by 1.5GHz and the relative bandwidth increased by 6.1% after adding parasitic patches, both of which doubled; the absolute bandwidth S22 of the antenna increased by 0.9GHz and the relative bandwidth increased by 3.7%. Therefore, through comparative analysis, it can be concluded that adding parasitic patches can effectively increase the bandwidth of the antenna.

[0125] Comparative analysis of structures with and without grating holes: Fig.24 As shown, by adding a hole grid structure between the M4 and M5 layers, the hole grid structure is used to suppress the near-field radiation of the antenna in the packaging cavity, which not only reduces the electromagnetic interference of the integrated antenna to the device in the cavity, but also improves the radiation efficiency of the antenna.

[0126] like Fig.25 As shown in the figure, through the simulation results, it can be clearly seen that after the hole-free grating structure, the radiation gain of the central operating frequency is only 5.78dB.

[0127] The antenna has a grid structure such as Fig.26 shown.

[0128] like Fig. 27 As shown in the figure, through the simulation results, it can be clearly seen that after the hole grid structure, the radiation gain of the central operating frequency is 6.13dB, which is 0.35dB higher than that of the non-hole grid structure. Therefore, through the comparative analysis of the results, it can be concluded that compared with the hole grid structure, the radiation gain of the non-hole grid structure antenna is reduced, so adding a hole grid structure can increase the radiation efficiency of the antenna.

[0129] refer to Fig.28 , which is the overall effect diagram of the antenna.

[0130] The parameters of the antenna substrate and the radiation patch are shown in Table 1:

[0131] Table 1 Dielectric substrate parameters (unit: mm)

[0132]

[0133] The radiation patch parameters are shown in Table 2:

[0134] Table 2 Patch parameter table (unit: mm)

[0135]

[0136] Where W is the antenna size of 7mm, S is the size of the square radiation patch of 2.75mm, the parasitic patch of 1.375mm, H is the thickness of ROS4350 of 0.9mm, the thickness of ROS4450 of 0.6mm, and h and E are the parameters required to determine the positions of parasitic patches, aperture grids, probes, pads, matching networks, etc.

[0137] Antenna simulation S11 curve and S22 curve are as follows Fig.29 shown.

[0138] According to the S parameters of the two ports of the antenna, it can be seen that the -10dB bandwidth range of the antenna is: S11 is from 23.1GHz to 26.1GHz, the center frequency is 24.5GHz, the relative bandwidth is 12.2%, covering part of the frequency band of 5G millimeter wave, and the curve has no obvious protrusion, the return loss is good, and the design index requirements can be met; S22 is from 22.9GHz to 25.9GHz, the center frequency is 24.5GHz, the relative bandwidth is 12.2%, covering part of the frequency band of 5G millimeter wave, and the curve has no obvious protrusion, the return loss is good, and the design index requirements can be met.

[0139] When the frequency of antenna port 1 is 23.8GHz, the return loss is relatively good, at -26.57dB; at 25.6GHz, the return loss is relatively good, at -19dB. When the frequency of antenna port 2 is 23.25GHz, the return loss is relatively good, at -23.30dB; at 25.6GHz, the return loss is relatively good, at -21dB. The parameter curve of the antenna is relatively smooth within the -10dB bandwidth range, without large protrusions, and the return loss of each frequency point is relatively average.

[0140] like Fig.30 As shown, it can be seen from the simulation results of the E-plane of the antenna that the gain of the E-plane is 6.08dB when the center operating frequency of the antenna is 24.5GHz, and the gain of the antenna is better when the E-plane is -90° to 90° clockwise, and the gain is relatively poor when the E-plane is 90° to 180° clockwise.

[0141] like Fig.31 As shown in the figure, the simulation results of the change of the 0° peak gain of the antenna E plane with the frequency show that the gain of the E plane is good when the center operating frequency of the antenna is 24.5GHz; 26GHz; 26.9GHz. And from the simulation result figure, it can be seen that the gain of the antenna is good in the 5G millimeter wave frequency band.

[0142] like Fig.32 As shown in the figure, the simulation results of the E-plane of the antenna show that the gain of the E-plane is 6dB when the center frequency is 24.5Ghz, and the gain of the H-plane is 0dB. The maximum gain of the antenna is 6.09dB.

[0143] The packaging materials have evolved from the initial alloy packaging to ceramic metal packaging, and then to plastic packaging. With the development of new materials, there are currently two ways to package antennas: plastic packaging and ceramic shell packaging.

[0144] The main material of plastic packaging is resin. The thermal conductivity of plastic packaging is low, only one-fiftieth of that of ceramic packaging. Because the corrosion resistance of resin is relatively poor, the corrosion resistance of plastic packaging is also very poor.

[0145] The main material of ceramic packaging is ceramic. Ceramic packaging is the main packaging technology for high reliability requirements and is very suitable for IC chip packaging. However, ceramic packaging also has obvious disadvantages. Compared with plastic packaging, the ceramic packaging process temperature is higher, so it will cause its processing cost to be higher. In addition, ceramic itself is fragile and easily damaged.

[0146] Low temperature hybrid ceramic (LTCC) has become a popular manufacturing technology for microwave and millimeter wave applications. The cost savings achieved by embedding common passive components into the substrate suggest that similar savings can be achieved by integrating the antenna into the LTCC package. Since the conductor layer in LTCC is screen printed, a planar antenna such as a microstrip patch is a good choice. Referring to Table 3, it was decided to use a ceramic housing for the antenna and IC chip packaging.

[0147] Table 3 Types of ceramics on the market

[0148]

[0149] according to Fig.33 From the top view of the shell, we can see that the size of the ceramic shell where the chip is placed is 5.7mm, and the size of the simulated antenna is 7mm, which just matches the size of the designed antenna. The size of the entire shell is 8.89mm, which is miniaturized. The height of the shell where the antenna is placed is 0.6mm, which just coincides with the thickness of the lower layer ROS4450 of the designed antenna.

[0150] Adjust the reference system of the antenna and the reference system of the ceramic housing, and place the antenna exactly into the ceramic package. The effect is as follows: Figure 34-36 As shown:

[0151] like Fig.37 As shown, it can be clearly seen that the excitation point of the antenna after packaging is located on the pad in the shell, and is connected to the chip in the next layer of the cavity through two red microstrip lines.

[0152] like Fig.38 As shown in the figure, through the simulation results, it can be clearly seen that the bandwidth range of the two ports of the antenna is: S11 is from 23.GHz-25.95GHz, the center frequency is 24.5GHz, the relative bandwidth is 12%, covering part of the frequency band of 5G millimeter wave, and can meet the requirements of the design indicators; S2 is from 22.2GHz-24.95GHz, the center frequency is 24.5GHz, the relative bandwidth is 11.2%, covering part of the frequency band of 5G millimeter wave, and can meet the requirements of the design indicators. When the frequency point of antenna port 1 is 24.85GHz, the return loss is relatively good, which is -25.44dB; when the frequency point of antenna port 2 is 24.7GHz, the return loss is relatively good, which is -34.11dB.

[0153] like Fig.39 As shown in the figure, through the simulation results, it can be clearly seen that after the antenna is packaged with the ceramic shell, the isolation is improved. The isolation is significantly improved within the 5G millimeter wave range and reaches the highest at 25.15GHz.

[0154] like Fig.40 As shown in the figure, through the simulation results, it can be clearly seen that after the antenna is packaged with the ceramic shell, the E-plane working center frequency of the packaged antenna is 6.85dB, and the center working frequency when not packaged is 6dB, which is an increase of 0.85dB.

[0155] like Fig.41 As shown in the simulation results, it can be clearly seen that after the antenna is packaged with ceramic, the radiation gain increases from 6.1dB to 7.48dB, a total increase of 1.38dB.

[0156] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal, characterized in that: The steps include: S1. Material selection: The antenna is composed of an upper composite substrate and a lower composite substrate. The upper composite substrate is arranged on the upper end of the lower composite substrate. The antenna is divided into five layers from bottom to top, namely, M1, M2, M3, M4 and M5 layers, and the upper composite substrate is the M5 layer; The thickness of the upper composite substrate is 0.9 mm; the thickness of the lower composite substrate is 0.6 mm, and the length of the substrates is 7 mm. S2. Patches and parasitic patches: a square radiating patch with corner cutting and slotting, 4 rectangular parasitic patches and 4 U-shaped parasitic patches. All patches are concentrated on the M5 layer. S3. Differential feeding: Using this method, the antenna is excited by two feeds with opposite phases, which increases the bandwidth and reduces the feed radiation. A matching network design is used, and the matching network is applied to a single-layer patch antenna with parasitic elements to achieve the design goals of increasing bandwidth and eliminating stray inductance. S4. Matching network: In order to overcome the bandwidth limitation, a matching feed network is designed; The feeding network connected to port 1 through pads and probes is located in the M2 layer. The probe is made of pec material. The size of the square pad connected to it is 0.35mm*0.43mm, and the length of the probe connected to the square pad is 0.15mm. The feeding network connected to port 2 through pads and probes is located on the M2 and M3 layers, and the probes are made of pec material; the size of the square pad located on the M2 layer is 0.35mm*0.43mm, and the length of the probe connected to it is 0.15mm; The diameter of the two circular pads connecting the feeding network located in the M3 layer and the feeding network located in the M2 layer are both 0.21 mm, and the length of the connected probe is 0.3 mm; The transmission line impedance of the matching network is 50Ω, and in each branch, there is a lossless half-wavelength transmission line connected between the two corresponding balanced ports. This design enables the required 180° phase to be obtained, further ensuring that the antenna is fed by differential feeding technology; S5. Aperture grid structure: A hole grid structure is added between the M4 and M5 layers, and the positions of the four sides are all 0.175mm away from the edge of the antenna; The hole grid material is made of pec, and the distance between the two adjacent cylinders is 0.265mm.

2. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 1, characterized in that: The dielectric constant of the upper composite substrate is 3.48, the dielectric constant of the lower composite substrate is 3.35, and the loss factors of the two dielectric materials are both 0.

004.

3. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 2, characterized in that: The two feeding ports and GND are on the M1 layer, and the feeding port is tangent to GND, which is convenient for antenna and chip packaging.

4. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 3, characterized in that: M2 to M4 are the layers where the matching network is located, and a hole grid structure is added between the M4 layer and the M5 layer.

5. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 4, characterized in that: In the step S2, the four U-shaped parasitic patches are rotationally symmetric through the square patch located in the center, the boundary distances between the four U-shaped parasitic patches and the square patch are all 0.1 mm, and the centers of the square patch and the parasitic patch are on the same line; Another four rectangular parasitic patches are located at the border of the antenna to form a square frame, and the size of the patch is: 7mm long and 0.5mm wide.

6. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 5, characterized in that: In the step S4, the diameters of the two circular pads are both 0.28 mm, and the length of the probe connected to the two circular pads is 1.35 mm.

7. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 6, characterized in that: In the step S4, the diameter of the other two circular pads of the M3 layer feeding network is 0.28 mm, and the length of the connected probe is 1.35 mm.

8. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 7, characterized in that: The model of the upper composite substrate is Rogers RO4350B, and the model of the lower composite substrate is Rogers RO4450T.

9. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 8, characterized in that: The rectangular patch slotting is a method for increasing bandwidth. The slotting changes the path of the current, so that the current path that reaches half the wavelength at a specific frequency is reduced, the number of half-wave oscillators is reduced, and thus the gain is reduced.

10. The method for preparing a dual-polarization packaged antenna for a 5G millimeter wave terminal according to claim 9, characterized in that: The bandwidth is increased. Although the slots will reduce the radiation efficiency, adding a hole grid structure to the antenna can reduce the impact of the slots on the radiation efficiency.

Images