TE20 mode LTCC patch antenna and radar based on SIW structure

Abstract

According to the TE20 mode LTCC patch antenna and radar based on the SIW structure, the SIW structure is applied to a reverse phase balance feed network and a slot coupling patch antenna, is applied to a high-gain TE20 mode LTCC patch antenna array with the frequency band of 77-81GHz and is packaged in an integrated antenna, and the TE20 mode LTCC patch antenna and radar based on the SIW structure have the performance of high gain and wide frequency band; the SIW structure and the LTCC multilayer structure are combined to realize a high-performance, miniaturized and highly integrated high-frequency microwave device, which is an important innovation in the technical field of radio frequency and microwave. The LTCC technology adopted by the invention can realize stacking of multiple layers of ceramic substrates, and provides a basis for manufacturing a multilayer SIW device; the SIW structure realizes a complex waveguide structure on the LTCC substrate, the performance and efficiency of the device are improved, and the formed array antenna has unique advantages in the development of millimeter wave packaging antennas.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic compatibility and antenna technology, specifically relating to a TE20 mode LTCC patch antenna and radar based on SIW structure. Background Technology

[0002] Research and applications in millimeter-wave communication and radar technologies are developing rapidly. Various institutions are deepening their research on the 77-81 GHz band, which, due to its short wavelength and high frequency, has been widely applied in various fields. In the future, with the popularization of 5G and the development of autonomous driving technology, the 77-81 GHz band will continue to be a key technological foundation, supporting innovation in intelligent transportation, communication, security, and other fields.

[0003] The shorter wavelength of millimeter waves shortens the transmission path within radio frequency devices, which is beneficial for the miniaturization and integration of millimeter-wave devices and systems. With the development of packaging technology, the concept of System in Package (SiP) has been proposed, integrating antennas with multifunctional chips within a single package to improve system integration and performance optimization. Correspondingly, the concept of Antenna in Package (AiP) has been introduced. With the development of the microelectronics industry, modern communication systems increasingly demand high-performance and miniaturized devices, making the design of LTCC antennas a research hotspot.

[0004] LTCC (Low-Temperature Co-fired Ceramic) packaged antennas are now widely used in millimeter-wave wireless systems. LTCC technology has the following characteristics: First, it can realize multi-layer three-dimensional structures, supporting high integration and complex designs. Second, it has excellent electrical characteristics, such as low dielectric loss, high dielectric constant, and good RF performance. Furthermore, LTCC device fabrication technology is mature, reliable, and suitable for high-frequency, millimeter-wave, and optoelectronic fields.

[0005] SIW (Slot-coupled Width) is a highly efficient design method for RF and microwave systems, using slot coupling to a patch antenna. The SIW structure, consisting of a dielectric substrate and a copper sheet, possesses waveguide characteristics, enabling efficient signal transmission, and is coupled to the patch antenna via a slot. This approach achieves high-performance, compact, and flexible signal transmission and radiation in RF and microwave systems. Through careful design of the SIW structure and patch antenna, efficient power transfer within the operating frequency range can be achieved. The size and shape of the slot can be adjusted to ensure optimal coupling efficiency. The SIW structure limits signal leakage, reduces system interference and radiation, and improves performance. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a TE20 mode LTCC patch antenna and radar based on SIW structure, so as to achieve higher integration and miniaturization design.

[0007] The technical solution adopted by this invention to solve the above-mentioned technical problems is: a TE20 mode LTCC patch antenna based on a SIW structure, including... The beneficial effects of this invention are as follows: 1. The TE20 mode LTCC patch antenna and radar based on SIW structure of the present invention apply SIW structure to reverse phase balanced feed network and slot-coupled patch antenna, and apply it to high-gain TE20 mode LTCC patch antenna array in 77-81GHz frequency band, and package it in integrated antenna, which has high gain and wide bandwidth performance, and realizes higher integration and miniaturization design.

[0008] 2. This invention combines the SIW structure with the multilayer structure of LTCC to achieve a high-performance, miniaturized, and highly integrated high-frequency microwave device. It is an important innovation in the fields of radio frequency and microwave technology, providing more design flexibility and performance advantages for modern communication and radar systems, and promoting the development of modern communication and radar technology.

[0009] 3. The LTCC process used in this invention enables the stacking of multilayer ceramic substrates, providing a foundation for fabricating multilayer SIW devices. The SIW structure can be combined with the multilayer structure of LTCC, enabling antennas and other devices to achieve higher integration and miniaturization. Furthermore, the SIW structure can easily realize complex waveguide structures on the LTCC substrate, improving device performance and efficiency. The resulting array antenna has unique advantages in the development of millimeter-wave packaged antennas.

[0010] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a propagation diagram of TE10 mode and TE20 mode in the SIW structure of this invention embodiment.

[0013] Figure 2 This is a 3D view of the TE20 mode LTCC patch antenna element according to an embodiment of the present invention.

[0014] Figure 3 This is a top view of the TE20 mode LTCC patch antenna element according to an embodiment of the present invention.

[0015] Figure 4 This is a diagram showing the reflection coefficient and corresponding gain of the TE20 mode LTCC patch antenna element according to an embodiment of the present invention.

[0016] Figure 5 This is the polar coordinate pattern of the TE20 mode LTCC patch antenna element in an embodiment of the present invention at 81 GHz.

[0017] Figure 6 This is a simulation result diagram of the S-parameters of the SIW structure reverse phase balanced feed network according to an embodiment of the present invention.

[0018] Figure 7 This is a 3D view of the TE20 mode LTCC patch antenna array according to an embodiment of the present invention.

[0019] Figure 8 This is a top view of the TE20 mode LTCC patch antenna array according to an embodiment of the present invention.

[0020] Figure 9 This is the normalized radiation pattern of the TE20 mode LTCC patch antenna array in an embodiment of the present invention at 77 GHz and 81 GHz.

[0021] In the diagram: 3. Antenna subarray; 4. Antenna cavity layer; 5. Feed layer; 6. Microstrip metal patch; 7. Dual slot; 8. TE10 mode transmission input port; 9. Metallized pillar; 10. Output port; 11. 1-to-2 power divider. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Example 1 See Figure 2 , 7 8. This embodiment includes a patch antenna radiating array and a reverse phase balanced feed network, with a total of 11 layers of LTCC material; The patch antenna array is composed of several antenna subarrays 3 arranged at a certain interval; the antenna subarray 3 includes an upper part of 1-3 layers of TE20 mode antenna cavity layers 4 for radiation, and 4-7 layers of TE20 mode feed layers 5 for input; the top layer of TE20 mode microstrip metal patch 6 is coupled and fed by the double slots 7 of the bottom layer of the antenna cavity, and uses two TE10 mode transmission input ports 8 with equal amplitude and opposite direction to simulate the transmission form of higher-order mode TE20 mode, and then coupled to a pair of patches on the upper layer through a pair of slots on the top layer of the transmission line for feeding; metallized pillars 9 are constructed around the radiating patch, connecting the upper and lower ground, forming an antenna radiation cavity for suppressing surface waves on the substrate; The reverse phase balanced feed network consists of 8-11 layers. The upper layers 8 and 9 utilize slots and gaps for multiple couplings to achieve a 1:16 equal-amplitude power distribution at the output port 10 of the feed network. Correspondingly, the two adjacent TE10 mode transmission input ports 8 of each antenna subarray, with equal amplitude and opposite direction, utilize the spatial half-wavelength displacement difference to achieve a 180-degree phase difference, simulating TE20 mode feeding. This structure also functions as a balanced feed and impedance transformation unit. The lower layers 10 and 11 utilize a 1:2 power divider 11 to achieve equal-amplitude power distribution at the input ports of the feed network. This input port also features an output adapter design to feed the antenna array.

[0024] This embodiment designs a TE20 mode LTCC patch antenna array based on the SIW structure. The SIW structure is applied to the reverse phase balanced feed network and the slot-coupled patch antenna. It is applied to a high-gain TE20 mode LTCC patch antenna array in the 77-81GHz frequency band and packaged in an integrated antenna. It has high gain and wide bandwidth performance, and achieves higher integration and miniaturization design.

[0025] Example 2 The structure of this embodiment is the same as that of Embodiment 1, the difference being that it is applied to a specific instance. Figure 1 This is a propagation diagram of the TE10 and TE20 modes in the SIW structure provided in this embodiment. Each LTCC layer has a sintering thickness of 0.092 mm, and the dielectric material used is DuPont 951 with a dielectric constant of 7.8. In the HFSS, regarding the excitation port, one TE20 mode wave port is set on the right end; two inverse TE10 mode wave ports are set on the left end, simulating the actual high-order mode electric field in the dielectric, with good transmission performance. Combination Figure 2 and Figure 3 The 3D structural schematic diagram and top view of the TE20 mode LTCC patch antenna unit shown provide further description of this embodiment.

[0026] Figure 2This is a 3D structural diagram of a TE20 mode LTCC patch antenna element, which consists of seven layers of LTCC material. The antenna element includes upper layers 1-3, which are TE20 mode antenna cavity layers for radiation, and layers 3-7, which are TE20 mode feed layers for input. The top TE20 mode microstrip metal patch is fed by a dual-slot coupling from the bottom layer of the antenna cavity. It uses two TE10 mode transmission patterns with equal amplitude and opposite direction to simulate the transmission pattern of the higher-order TE20 mode, and then feeds it to a pair of patches on the upper layer through a pair of slots on the top layer of the transmission line. Metallized pillars are built around the radiating patch and connected to the upper and lower grounds to form an antenna radiation cavity for suppressing surface waves on the substrate.

[0027] Figure 3 The top view shows the model's dimensions as follows: Wm=3.5, Lm=2.2, Wp=0.8, Lp=1.7, Ws=0.4, Ls=1, ds=0.8, ts=0.55, tc1=0.35, tc2=0.75, dc2=0.3, tc3=0.67, tc4=0.77, dc4=0.8, Wf=2.3 (unit: mm).

[0028] The reflection coefficient and corresponding gain results of the TE20 mode LTCC patch antenna element are as follows: Figure 4 As shown, the designed antenna has a reflection coefficient of less than -10dB at port 1 in the frequency range of 77.2 GHz-84 GHz, and the gain at each frequency point is above 6dB, with good in-band gain flatness. Figure 5 The polar coordinate system radiation pattern of the TE20 mode LTCC patch antenna element provided in this embodiment is shown at 81 GHz, and the radiation pattern shows good radiation performance.

[0029] Combination Figure 6 , Figure 7 The schematic diagram of the SIW reverse phase balanced feed network and the S-parameter simulation results shown in the figure further describe this embodiment.

[0030] Figure 7The 3D structural diagram of the TE20 mode LTCC patch antenna array includes a patch antenna radiating array and a reverse phase-balanced feed network, comprising 11 layers of LTCC material. The reverse phase-balanced feed network combines the characteristics of SIW waveguides with the advantages of reverse phase-balanced technology. This network structure embeds the circuitry into the dielectric substrate using LTCC technology, utilizing the waveguide slot coupling characteristics and the spatial half-wavelength displacement difference to split the signal into two out-of-phase signals. The reverse phase-balanced feed network comprises layers 8-11. The upper layers 8 and 9 utilize slots and gaps for multiple couplings to achieve a 1:16 equal-amplitude power distribution at the feed network output ports. This corresponds to a 180-degree phase difference between the two adjacent TE10 mode transmission input ports of each antenna subarray, simulated by the spatial half-wavelength displacement difference. The lower layers 10 and 11 utilize a 1:2 power divider to achieve equal-amplitude power distribution at the feed network input ports.

[0031] Figure 6 The following are the S-parameter simulation results of the SIW structure reverse phase balanced feed network provided in this embodiment: In the frequency range of 77GHz-86.5GHz, the reflection coefficient of port 1 is less than -10dB, and the coupling degree is close to the theoretical value; the phase difference of the reflection coefficient corresponding to the in-phase port tends to 0°, and the phase difference of the reverse port tends to 180°, so equal amplitude and in-phase power output can be achieved.

[0032] Combination Figure 7 , Figure 8 The schematic diagram of the TE20 mode LTCC patch antenna array structure shown provides a further description of this embodiment.

[0033] The designed TE20 mode LTCC patch antenna array based on SIW structure includes a patch antenna radiating array and a reverse phase-balanced feed network, comprising a total of 11 layers of LTCC material. The antenna array is composed of 2*4 elements arranged in a 2x4 configuration. By applying LTCC technology, the high-gain TE20 mode antenna is combined with the SIW feed network, ultimately achieving a vertically stacked and horizontally integrated design of the antenna array.

[0034] Further investigation was conducted into the radiation performance of the TE20 mode LTCC patch antenna array. The radiation pattern of a 2×4 antenna array was calculated using HFSS, as shown below. Figure 9 As shown, the array exhibits good radiation performance in the 77GHz-81GHz frequency band.

[0035] This embodiment combines the SIW structure with the multilayer structure of LTCC to achieve a high-performance, miniaturized, and highly integrated high-frequency microwave device. It is an important innovation in the fields of radio frequency and microwave technology, providing more design flexibility and performance advantages for modern communication and radar systems, and promoting the development of modern communication and radar technology.

[0036] Example 3 A radar employs the TE20 mode LTCC patch antenna array based on the SIW structure described in the above embodiments.

[0037] It should be noted that, depending on the implementation needs, the various components described in this application can be broken down into more steps / components, or two or more components or parts of the operation of components can be combined into new components to achieve the purpose of this invention.

[0038] The above embodiments are only used to illustrate the design concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made based on the principles and design ideas disclosed in the present invention are within the protection scope of the present invention.

Claims

1. A TE20 mode LTCC patch antenna based on SIW structure, characterized in that: This includes the patch antenna array located above and the corresponding reverse phase balanced feed network below; The patch antenna array comprises several equidistantly arranged antenna subarrays; the antenna subarrays include a TE20 mode antenna cavity layer and a TE20 mode feed layer; The top layer of the TE20 mode antenna cavity layer is provided with a TE20 mode microstrip metal patch, and the bottom layer at the corresponding position is provided with a double slot for coupling and feeding power to the TE20 mode microstrip metal patch. The top layer of the TE20 mode feed layer is equipped with a TE10 mode transmission input port, which is used to simulate the transmission form of the higher-order TE20 mode to feed power to the dual slots. The upper layer of the reverse phase balanced feed network is equipped with a feed network output port, which is used to feed the TE10 mode input port. The lower layer of the reverse phase balanced feeder network has a feeder network input port for feeding power to the feeder network output port.

2. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: In TE20 mode, the antenna cavity layer is located in the upper part; The TE20 mode feed layer is located below the TE20 mode antenna cavity layer.

3. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: The two TE10 mode transmission input ports of the TE20 mode feed layer are in opposite directions with equal amplitude, which is used to achieve a 180-degree phase difference through the spatial upper half-wavelength displacement difference, thereby simulating the TE20 mode feed.

4. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: The top layer of the TE20 mode antenna cavity layer is also surrounded by a metallized pillar connecting to the ground layer, which is used to suppress the antenna radiation cavity of the substrate surface wave.

5. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: Both the bottom layer of the TE20 mode antenna cavity layer and the bottom layer of the TE20 mode feed layer are ground layers.

6. The TE20 mode LTCC patch antenna based on SIW structure according to claim 5, characterized in that: The top layer of the TE20 mode power supply layer is also equipped with metallized pillars connecting to the ground layer around the TE10 mode transmission input port; The metallized pillars of the TE20 mode feed layer have openings in the direction of the TE10 mode transmission input port.

7. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: The upper layer of the reverse phase balanced feed network also has slots and gaps for distributing the power at the output port of the feed network through multiple couplings with equal amplitude.

8. The TE20 mode LTCC patch antenna based on SIW structure according to claim 1, characterized in that: The lower layer of the reverse phase balanced feeder network also has a power divider, which is used to distribute the power at the input port of the feeder network in an equal manner.

9. The TE20 mode LTCC patch antenna based on SIW structure according to claim 8, characterized in that: The input port of the power supply network also serves as an output converter to power the antenna array.

10. A radar, characterized in that: The TE20 mode LTCC patch antenna array based on the SIW structure as described in any one of claims 1 to 9 is employed.

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