Combiner and vehicle

Abstract

The invention provides a combiner and a vehicle. The combiner and the vehicle are used for solving the problems that an existing combiner is large in size and high in power consumption. The combiner comprises a first filter and a second filter which work at different frequency bands; the micro-strip filtering power divider is in cascade connection with the first filter and the second filter; the microstrip filtering power divider combines or splits the signal of the first filter and the signal of the second filter; the first filter and the second filter are single-cavity multi-mode filters.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a combiner and a vehicle. Background Art

[0002] With the rapid development of 5G (fifth-generation) technology, V2X communication systems are becoming increasingly important in intelligent transportation systems. To achieve this goal, developing compact, high-performance 5G communication equipment capable of multi-band communication is crucial. RF combiners play a crucial role in integrating multi-band signals. To balance size, cost, and performance, designing compact, high-performance RF combiners suitable for 5G smart car multi-band communication systems has become a key research topic.

[0003] There are three common types of combiners: microstrip, waveguide, and coaxial cavity. Microstrip combiners offer advantages such as small size and light weight, but suffer from high insertion loss. Waveguide and coaxial cavity combiners offer advantages such as high power handling and low loss, but are larger in size. Summary of the Invention

[0004] The present application provides a combiner and a vehicle, which are used to solve the problems of large size and high power consumption of existing combiners.

[0005] The technical solution of the present invention is: The present application provides a combiner, comprising: A first filter and a second filter operating in different frequency bands; a microstrip filter power splitter cascaded with the first filter and the second filter; The microstrip filter power splitter combines or splits the signal of the first filter and the signal of the second filter; The first filter and the second filter are single-cavity multi-mode filters.

[0006] Preferably, the single-cavity multimode filter comprises: The housing has a cavity; At least two resonant columns are disposed in the cavity of the housing; an input coupling port and an output coupling port; an input feed probe and an output feed probe; The input feeding probe is electrically connected to the input coupling port and to one of the resonant columns, and is used to transmit the signal from the input coupling port to the resonant column; The output feeding probe is electrically connected to the output coupling port and to another resonant column, and is used to transmit the signal from the resonant column to the output coupling port.

[0007] Preferably, the top of each resonant column is provided with a coupling enhancement structure extending toward the center of the cavity, for enhancing electromagnetic coupling between the resonant columns.

[0008] Preferably, the single-cavity multimode filter further includes: at least one tuning element, for adjusting the resonant frequency of each of the resonant columns; At least one coupling adjustment element, used to adjust the coupling strength between the resonant columns; At least one tuning element and at least one coupling element are mounted on the cover plate of the housing.

[0009] Preferably, the first filter is a single-cavity four-mode filter, and the number of the resonant columns is four; A coupling element is provided between two adjacent resonant columns, and a coupling element is provided at the center of a plurality of resonant columns; Among them, the single-cavity four-mode filter has four different resonant modes; the first resonant mode has four magnetic rings in different directions; the fourth resonant mode produces a large magnetic ring; the first resonant mode and the fourth resonant mode are a pair of differential modes; the second resonant mode and the third resonant mode are a pair of degenerate modes.

[0010] Preferably, the number of the tuning elements is the same as the number of the resonant columns, and one tuning element is provided directly above each of the resonant columns, for independently adjusting the resonant frequency of each resonant column.

[0011] Preferably, the single-cavity multi-mode filter is a single-cavity dual-mode filter, there are two resonant columns, and the single-cavity dual-mode filter has two different resonant modes.

[0012] Preferably, a 180° phase difference is introduced between the input coupling port and the output coupling port of the single-cavity dual-mode filter to optimize the frequency response.

[0013] Preferably, the operating frequency band of the first filter is between 3320-3660 MHz, and the operating frequency band of the second filter is between 4830-4940 MHz.

[0014] Preferably, the microstrip filter power divider includes: a first port, a second port, and a third port; an isolation resistor connected between the second port and the third port; a first transmission line and a first open line connected to the first port and the second port; a second transmission line and a second open line connected to the first port and the third port; The second port is electrically connected to the first filter, and the third port is electrically connected to the second filter.

[0015] Preferably, the first filter and the second filter are electrically connected to the microstrip filter power divider using a 50Ω coaxial cable.

[0016] The present application also provides a vehicle, comprising the above-mentioned combiner.

[0017] The beneficial effects of the present invention are: Traditional cavity combiners usually use a multi-cavity cascade method to achieve broadband design, and each cavity has a resonant frequency; the combiner generally has at least two operating frequency bands, and each frequency band requires a filter designed using a single-cavity cascade method, which will result in a larger combiner size and increase power consumption and cost. The second filter in the combiner of the present application is implemented using a single-cavity dual-mode, and the first filter is implemented using a single-cavity four-mode. Compared with the multi-cavity cascade design method, this design method reduces the number of cavities in the first filter and the second filter to one-fourth and one-half of the original, effectively reducing the required physical space and realizing miniaturization of the equipment. Compared with microstrip combiners, cavity-structured combiners have the advantages of high power capacity and low insertion loss. Therefore, the combiner based on a single-cavity multi-mode filter in the present application not only has the characteristics of high power capacity and low insertion loss of the cavity, but also has the advantages of fewer cavities and smaller physical size.

[0018] In addition, the design of the single-cavity multimode filter reduces the loss of signals when transmitting between different cavities; since the signal is processed through the resonant mode in the same cavity, the coupling loss and transmission loss that may exist in the multi-cavity design are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 Schematic diagram of the structure of the combiner in the embodiment of the present application; Figure 2 Schematic diagram of the structure of a single-cavity four-mode filter; Figure 3 for Figure 2 Schematic diagram of the top view structure; Figure 4 for Figure 2 A schematic diagram of the front structure of FIG. Figure 5 The internal magnetic field distribution diagram of the first resonant mode (3.32 GHz) of the single-cavity quad-mode filter; Figure 6This is the internal magnetic field distribution diagram of the second resonance mode (3.59GHz) of the single-cavity four-mode filter; Figure 7 This is the internal magnetic field distribution diagram of the third resonant mode (3.59GHz) of the single-cavity four-mode filter; Figure 8 The internal magnetic field distribution diagram of the third resonant mode (3.87 GHz) of the single-cavity four-mode filter; Figure 9 Schematic diagram of the change of the eigenfrequency of the resonant mode of the single-cavity four-mode filter with the height H2 of the resonant column; Figure 10 Schematic diagram of the change of the eigenfrequency of the resonant mode of the single-cavity four-mode filter with the distance L2+G between the resonant column and the center of the cavity; Figure 11 Schematic diagram of the change of the effective Q value of the resonant mode of the single-cavity four-mode filter with the distance D1 between the input feeding probe and the second resonant column; Figure 12 Schematic diagram of the change of the effective Q value of the resonant mode of the single-cavity four-mode filter with the height D3 of the input feeding probe; Figure 13 The simulation results of the insertion loss and return loss of the resonant mode of the single-cavity four-mode filter are shown in Figure 2. Figure 14 Schematic diagram of the structure of a single-cavity dual-mode filter Figure 1 ; Figure 15 Schematic diagram of the structure of a single-cavity dual-mode filter Figure 2 ; Figure 16 The simulation results of the insertion loss and return loss of the resonant mode of the single-cavity dual-mode filter are shown in Figure 2. Figure 17 It is a structural diagram of the microstrip filter power divider; Figure 18 This is the S-parameter simulation test result diagram of the combiner. DETAILED DESCRIPTION

[0020] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0021] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0022] In the present invention, unless otherwise specified, directional words such as "up" and "down" are generally used with respect to the directions shown in the drawings, or with respect to the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "left" and "right" are generally used with respect to the left and right shown in the drawings; "inside" and "outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0023] Reference Figure 1 , an embodiment of the present invention provides a combiner, comprising: A first filter BPF1 and a second filter BPF2 operating in different frequency bands; a microstrip filter power divider PD cascaded with the first filter BPF1 and the second filter BPF2; The microstrip filter power splitter PD combines or splits the signal of the first filter BPF1 and the signal of the second filter BPF2; The first filter BPF1 and the second filter BPF2 are single-cavity multi-mode filters.

[0024] Traditional cavity combiners typically use a multi-cavity cascade approach to achieve broadband design, with each cavity having a resonant frequency. Combiners generally have at least two operating frequency bands, and each band requires a filter designed using a single-cavity cascade approach. This results in a larger combiner size, increased power consumption, and increased cost.

[0025] In the combiner of the embodiment of the present application, the second filter BPF2 is implemented using a single-cavity dual-mode, and the first filter BPF1 is implemented using a single-cavity quad-mode. Compared to a multi-cavity cascade design, this design reduces the number of cavities in the first filter BPF1 and the second filter BPF2 to one-quarter and one-half of the original, effectively reducing the required physical space and achieving miniaturization of the device. Compared to microstrip combiners, cavity-structured combiners have the advantages of high power capacity and low insertion loss.

[0026] In addition, since the signal is processed through the resonant mode in the same cavity, the coupling loss and transmission loss that may exist in the multi-cavity design are avoided. Therefore, the design of the single-cavity multi-mode filter reduces the loss of the signal when it is transmitted between different cavities.

[0027] In the embodiment of the present application, the operating frequency band of the first filter BPF1 is between 3320-3660 MHz, and the frequency band of the second filter BPF2 is between 4830-4940 MHz.

[0028] In an embodiment of the present application, a single-cavity multimode filter includes: The housing has a cavity; At least two resonant columns are disposed in the cavity of the housing; an input coupling port and an output coupling port; an input feed probe and an output feed probe; The input feeding probe is electrically connected to the input coupling port and to one of the resonant columns, and is used to transmit the signal from the input coupling port to the resonant column; The output feeding probe is electrically connected to the output coupling port and to another resonant column, and is used to transmit the signal from the resonant column to the output coupling port.

[0029] The single-cavity multimode filter uses multiple resonant columns in a housing to support multiple resonant modes, thereby being able to process signals in multiple frequency bands, reducing the number of cavities and achieving miniaturization of the filter. Energy is transferred through the input feed probe and the output feed probe, which can effectively excite the required resonant modes. The design also has low insertion loss, high selectivity and good frequency response characteristics, and can accurately select signals in a specific frequency band while suppressing signals in other frequency bands. In addition, the resonant frequency and coupling strength of the filter can be flexibly adjusted by adjusting the position of the feed probe to adapt to different working conditions and performance requirements. This design is particularly suitable for communication systems that are space-constrained and require high-performance, multi-band processing capabilities, such as 5G communication equipment and vehicle communication systems.

[0030] In the single-cavity multimode filter of the embodiment of the present invention, a coupling enhancement structure is specially designed to further optimize the distribution of the electromagnetic field and enhance the coupling effect between the resonant columns. Specifically, the top of each resonant column is provided with a coupling enhancement structure extending toward the center of the cavity.

[0031] The aforementioned coupling-enhancing structures can be designed in various shapes, including rectangular, circular, elliptical, or triangular. The choice of these shapes depends on the specific electromagnetic field distribution requirements and optimization goals. For example, rectangular blocks can provide stronger capacitive coupling, while circular blocks can achieve a more uniform magnetic field distribution.

[0032] Coupling enhancement structures are usually made of conductive materials, such as aluminum or copper; these materials have good electromagnetic properties and can effectively enhance the coupling effect of the electromagnetic field.

[0033] The coupling enhancement structure increases the metal area at the top of the resonant column, thereby enhancing the capacitive coupling between the resonant columns. The enhanced capacitive coupling can improve the distribution of the electromagnetic field, making the signal transmission between the resonant columns more efficient.

[0034] The coupling enhancement structure can also enhance the magnetic field coupling between the resonant columns by changing the distribution of the magnetic field. By properly designing the position and shape of the coupling enhancement structure, the magnetic field path can be optimized, further improving the coupling efficiency.

[0035] By enhancing the electromagnetic coupling between the resonant columns, the frequency response characteristics of the single-cavity multimode filter are significantly optimized, achieving a flatter passband and a steeper stopband, thereby improving the selectivity of the filter.

[0036] The enhanced coupling effect helps reduce signal loss during transmission, thereby lowering insertion loss, which is crucial for maintaining signal strength and communication quality.

[0037] By optimizing the coupling enhancement structure, a wider bandwidth can be achieved, allowing the filter to process a wider frequency range.

[0038] The design of the coupling enhancement structure enables the filter to achieve high-performance electromagnetic coupling while maintaining miniaturization. This design is particularly suitable for communication systems that require miniaturization and high performance.

[0039] In the embodiments of the present application, tuning elements and coupling elements are specifically introduced to achieve fine adjustment of the resonant frequency and coupling strength. The addition of these elements provides great flexibility and accuracy for optimizing the performance of the filter. Specifically, the single-cavity multimode filter also includes: at least one tuning element, for adjusting the resonant frequency of each of the resonant columns; At least one coupling adjustment element, used to adjust the coupling strength between the resonant columns; At least one tuning element and at least one coupling element are mounted on the cover plate of the housing.

[0040] The single-cavity multimode filter design of the present invention incorporates tuning elements and coupling elements to achieve fine-tuning of the resonant frequency and coupling strength. These elements provide significant flexibility and precision in optimizing filter performance.

[0041] To facilitate tuning and coupling, both the tuning element and the coupling element are mounted on the housing cover. The tuning element fine-tunes the resonant frequency by varying the electrical length or capacitance of the resonant columns, while the coupling element optimizes the coupling strength by adjusting the electromagnetic field distribution between the resonant columns. This integrated design allows the filter to easily cope with frequency drift and coupling variations in practical applications, ensuring stable and reliable signal transmission.

[0042] The synergistic effect of tuning elements and coupling elements allows the performance of single-cavity multimode filters to be fully optimized. Specifically, the tuning elements can precisely adjust the resonant frequency of each resonant column, ensuring efficient operation of the filter within the target frequency band while reducing frequency deviations caused by manufacturing errors or environmental changes. The coupling elements further optimize the coupling efficiency between the resonant columns, enhancing signal transmission between different resonant modes and improving the selectivity and bandwidth of the filter. This comprehensive adjustment capability enables the filter to maintain low insertion loss and high isolation when processing multi-band signals, significantly improving the overall performance of the communication system.

[0043] The flexibility and precision of this design enable the single-cavity multimode filter to be widely used in various communication scenarios, including but not limited to 5G communications, the Internet of Vehicles (IoV), and satellite communications. In 5G communications, the filter can accurately process signals in multiple frequency bands to meet the needs of high-speed data transmission. In IoV applications, its high selectivity and low insertion loss ensure stable and reliable communication between vehicles and infrastructure. Furthermore, through the adjustment of tuning and coupling elements, the filter can adapt to different operating environments and signal conditions, demonstrating strong adaptability and versatility.

[0044] Based on the above structural design of the single-cavity multi-mode filter, the embodiments of the present application provide specific structural designs of the first filter BPF1 and the second filter BPF2. The first filter BPF1 is a single-cavity quad-mode filter, wherein the number of resonant columns is four, a coupling element is provided between two adjacent resonant columns, and a coupling element is provided at the center of multiple resonant columns.

[0045] Reference Figure 2-Figure 4 The single-cavity quad-mode filter in the embodiment of the present application specifically includes: a rectangular cavity Cav, a first resonant column R1, a second resonant column R2, a third resonant column R3, a fourth resonant column R4, an input coupling port SMA1 with a 50-ohm impedance, an output coupling port SMA2 with a 50-ohm impedance, an input feeding probe P1, an output feeding probe P2, a first tuning screw S2, a second tuning screw S4, a third tuning screw S6, a fourth tuning screw S8, a first adjusting coupling screw S1, a second adjusting coupling screw S3, a third adjusting coupling screw S5, a fourth adjusting coupling screw S7, and a fifth adjusting coupling screw S9.

[0046] In the embodiment of the present application, the input coupling port SMA1 and the output coupling port SMA2 both have an impedance of 50 ohms.

[0047] The first resonant column R1, the second resonant column R2, the third resonant column R3, and the fourth resonant column R4 are evenly distributed in the rectangular cavity, forming a symmetrical layout. They can be cylindrical or other suitable shapes, installed at the bottom of the cavity, with a uniform height and a certain gap between the top and the cavity cover.

[0048] The top of each resonant column has a coupling enhancement structure extending toward the center of the cavity. These structures can be protruding metal sheets or other shapes, which are used to enhance the electromagnetic coupling between the resonant columns.

[0049] Reference Figure 2 The input coupling port SMA1 is located on the side of the rectangular cavity and is electrically connected to the first resonant column R1 through the input feeding probe P1, transmitting the signal from the input coupling port SMA1 to the first resonant column R1. Specifically, one end of the input feeding probe P1 is connected to the input coupling port SMA1, and the other end is inserted into the cavity of the housing and contacts the side or top of the first resonant column R1 to achieve electrical connection.

[0050] The output coupling port SMA2 is located on the side of the rectangular cavity, opposite or adjacent to the input coupling port SMA1. It has a 50-ohm impedance and is used for signal output. One end of the output feed probe P2 is connected to the output coupling port SMA2, while the other end is inserted into the cavity of the housing and contacts the side or top of the fourth resonant column R4, establishing an electrical connection. Through the electrical connection between the output feed probe P2 and the fourth resonant column R4, the signal is transmitted from the fourth resonant column R4 to the output coupling port SMA2.

[0051] Reference Figure 2 The first tuning screw S2 is located directly above the first resonant column R1. By screwing the cavity cover in or out, the coupling degree with the first resonant column is changed, thereby independently adjusting the resonant frequency of the first resonant column R1. The second tuning screw S4 is located directly above the second resonant column R2 and is used to adjust the resonant frequency of the second resonant column R2. The third tuning screw S6 is located directly above the third resonant column R3 and is used to adjust the resonant frequency of the third resonant column R3. The fourth tuning screw S8 is located directly above the fourth resonant column R4 and is used to adjust the resonant frequency of the fourth resonant column R4.

[0052] Reference Figure 2The first coupling adjustment screw S1 is located between the first resonant column R1 and the second resonant column R2, and is used to adjust the coupling strength between them. The second coupling adjustment screw S3 is located between the second resonant column R2 and the third resonant column R3, and is used to adjust the coupling strength between them. The third coupling adjustment screw S5 is located between the third resonant column R3 and the fourth resonant column R4, and is used to adjust the coupling strength between them. The fourth coupling adjustment screw S7 is located between the first resonant column R1 and the fourth resonant column R4, and is used to adjust the coupling strength between them. The fifth coupling adjustment screw S9 is located at the center of the four resonant columns, and is used to adjust the overall coupling strength, and can comprehensively adjust the coupling between multiple resonant columns.

[0053] In order to further explain the working mechanism of the single-cavity four-mode resonator, the simulation software High Frequency Structure Simulator (HFSS) is used in the embodiment of the present application to perform eigenmode analysis. Figure 5-8 The magnetic field distribution of the four resonant modes of the single-cavity four-mode filter (BPF1) is given. Figure 5 It is observed that the first resonance mode has four magnetic rings with different directions, which can be equivalent to four coaxial resonators. Figure 8 The fourth resonant mode generates a large magnetic ring, which can be equivalent to a coaxial cavity, so Figure 8 The fourth resonant mode in Figure 5 The differential mode of the first resonant mode. Figure 6 The second resonant mode and Figure 7 The third resonant mode in the CMOS is a pair of degenerate modes, with the two modes having the same resonant frequency and spatially orthogonal magnetic field distributions. In the embodiment of the present application, the eigenfrequency of the first resonant mode is 3.32 GHz, the eigenfrequency of the second resonant mode is 3.59 GHz, the eigenfrequency of the third resonant mode is 3.59 GHz, and the eigenfrequency of the fourth resonant mode is 3.87 GHz.

[0054] Figure 9-10 The effects of different parameters on the eigenfrequencies of the four resonant modes are shown. Figure 9 It can be seen from the figure that as the height H2 of the resonant column increases, the eigenfrequencies of the four resonant modes gradually decrease. Figure 10 It can be seen that as the distance L2+G between the resonant column and the center of the cavity increases, the eigenfrequencies of the four resonant modes gradually increase. This is due to the smaller equivalent cavity size of the four resonant modes. Therefore, by determining the appropriate H2, L2, and G, the eigenfrequencies of the four resonant modes can be controlled.

[0055] In order to excite these four resonant modes, the single-cavity four-mode filter proposed in the embodiment of the present invention uses a capacitive coupling feeding structure, such as Figure 5The external feed probe uses a 50Ω SMA. Figure 11 and Figure 12 The figure shows how the loaded Q value varies with the distance D1 between the input feed probe P1 and the first resonant column R1 and the height H3 of the input feed probe P1. It can be seen that as D1 increases, the loaded Q values ​​of resonant modes 1 and 2 gradually increase, while the loaded Q values ​​of resonant modes 3 and 4 first decrease and then increase. Furthermore, the loaded Q values ​​of resonant modes 3 and 4 are proportional to H3. Therefore, by selecting the appropriate values ​​of D1 and H3, the external coupling of the filter can be controlled.

[0056] Figure 13 The simulation results of the insertion loss (|S21|) and return loss (|S11|) of the single-cavity quad-mode filter in the embodiment of the present application are shown. Figure 13 It can be seen that its operating frequency range is 3330-3660MHz; the 3-dB bandwidth is 330MHz (relative bandwidth: 9.4%); the insertion loss and return loss are 0.19dB and 17dB respectively; the high-frequency and low-frequency out-of-band suppression are 20dB@6GHz and 80dB@0.1GHz respectively.

[0057] By controlling these resonant modes of a single-cavity quad-mode filter, a compact filter with wide bandwidth and multi-band characteristics can be designed. This design provides a novel miniaturized dual-band 5G combiner solution for automotive multi-band communication systems.

[0058] Figure 14 and Figure 15 A schematic diagram of the single-cavity dual-mode filter (BPF2) is presented. This single-cavity dual-mode filter consists of a cavity and two resonant columns. This resonator structure is essentially the same as the single-cavity quadruple-mode resonator, except that two resonant columns are sufficient to meet the required operating bandwidth.

[0059] In the application examples, the main body of the single-cavity dual-mode filter is a rectangular cavity (Cav), made of aluminum with excellent conductivity and electromagnetic shielding properties. An inner cavity is formed within the cavity to accommodate two resonant columns. The shape and size of the cavity are designed based on the resonant frequency and coupling requirements, and its inner surface is silver-plated to ensure stable and consistent electromagnetic performance.

[0060] The single-cavity dual-mode filter has a cover plate on top of the cavity to seal the cavity. The cover plate is fixed to the cavity by screws or welding, and a sealing ring or sealant is used to ensure good electromagnetic shielding and airtightness.

[0061] In a single-cavity dual-mode filter, the first resonant column R1 and the second resonant column R2 are evenly distributed within the cavity, typically in a symmetrical layout. They are made of aluminum, which offers excellent conductivity and processability. Each resonant column can be cylindrical or other suitable geometric shape, with its size and position designed based on the desired resonant frequency and coupling relationship.

[0062] A coupling enhancement structure is provided at the top of the first resonant column R1 and the second resonant column R2, which is usually a metal sheet or other shape extending toward the center of the cavity, for enhancing the electromagnetic coupling between the two resonant columns.

[0063] For a single-cavity dual-mode filter, the input coupling port SMA1 is located on the side of the rectangular cavity. It is electrically connected to the first resonant column R1 via the input feed probe P1, transmitting the signal from the input coupling port to the first resonant column. Specifically, one end of the input feed probe P1 is connected to the input coupling port SMA1, while the other end is inserted into the cavity and contacts the side or top of the first resonant column R1, achieving electrical connection.

[0064] For a single-cavity dual-mode filter, the output coupling port SMA2 is located on the side of the rectangular cavity, opposite or adjacent to the input coupling port. It has a 50-ohm impedance and is used for signal output. One end of the output feed probe P2 is connected to the output coupling port SMA2, while the other end is inserted into the cavity and contacts the side or top of the second resonant column R2, establishing an electrical connection. Through the electrical connection between the output feed probe P2 and the second resonant column R2, the signal is transmitted from the second resonant column R2 to the output coupling port.

[0065] Figure 16 The simulation results of the insertion loss (|S21|) and return loss (|S11|) of the single-cavity dual-mode filter in the embodiment of the present application are shown. Figure 16 As can be seen, the single-cavity dual-mode filter operates in the 4800-4900 MHz frequency range, with a 3-dB bandwidth of 100 MHz (relative bandwidth: 2.1%), insertion loss and return loss of 0.45 dB and 16 dB, respectively. High-frequency and low-frequency out-of-band rejection are 33 dB at 4.98 GHz and 33 dB at 4.31 GHz, respectively. A 180° phase difference is introduced between the input and output coupling ports of this single-cavity dual-mode filter, creating a transmission zero to the right of the passband. This further improves the roll-off performance of the single-cavity dual-mode filter.

[0066] Reference Figure 17 , the microstrip filter power divider in the embodiment of the present application includes: A first port SMA1, a second port SMA2 and a third port SMA3; an isolation resistor connected between the second port SMA2 and the third port SMA3; a first transmission line and a first open line connected to the first port SMA1 and the second port SMA2; a second transmission line and a second open line connected to the first port SMA1 and the third port SMA3; The second port SMA2 is electrically connected to the first filter BPF1 , and the third port SMA3 is electrically connected to the second filter BPF2 .

[0067] The second port, SMA2, is electrically connected to the first filter, BPF1, via a 50Ω coaxial cable. This transmits the signal distributed by the power splitter to the first filter, BPF1, for further filtering. The third port, SMA3, is electrically connected to the second filter, BPF2, via a 50Ω coaxial cable. This transmits the signal distributed by the power splitter to the second filter, BPF2, for further filtering. The 50Ω coaxial cable is chosen to ensure good impedance matching during signal transmission, reduce reflection loss, and improve signal transmission efficiency.

[0068] The first port, SMA1, serves as the input port and is typically connected to a signal source to receive the input signal. The signal source's impedance must match the power divider's input impedance to achieve optimal signal transmission. The output ports of the first and second filters, BPF1 and BPF2, are typically connected to subsequent load circuits, such as antennas and amplifiers. The impedance of the load circuit must also match the filter's output impedance to ensure good signal performance during subsequent processing.

[0069] In the embodiment of the present application, a broadband filter power splitter is used as the three-port connection network of the combiner. Figure 17 As can be seen, this power divider is based on a traditional Wilkinson power divider with two open-circuit branches added. By adding these open-circuit branches, the microstrip filter power divider creates a transmission zero on either side of the passband, effectively suppressing signals outside the passband and achieving broadband filtering. Compared to traditional power dividers, this filter offers superior filtering performance and is suitable for applications requiring broadband filtering.

[0070] The isolation resistor design provides good isolation between the second and third ports, reducing signal crosstalk between the two ports. This is particularly important in multi-channel communication systems, as it prevents signal interference and improves system performance and reliability.

[0071] Among them, in the embodiment of the present application, the relative dielectric constant of the dielectric plate of the microstrip filter power divider is 2.65, and the loss tangent is 0.0019. The thickness of the dielectric plate is 0.76mm. The thickness of the metal copper is 0.035mm. After simulation optimization, its operating frequency range is 2220-6340MHz, the 1-dB bandwidth is 4120MHz (relative bandwidth: 96%), the return loss is better than 15dB, and the power distribution ratio is approximately 2:1. Therefore, the power divider can meet the working requirements of high and low frequency filters.

[0072] Figure 18 The S parameters of the dual-band 5G combiner simulation and test are shown. Figure 18 The simulation and test results show good consistency. The low-frequency filter's measured operating frequency range is 3320-3660 MHz, with a 3-dB bandwidth of 340 MHz (9.7% relative bandwidth). The measured insertion loss and return loss are 0.25 dB and 15 dB, respectively. The high-frequency and low-frequency out-of-band rejection are 26 dB at 6 GHz and 87 dB at 0.1 GHz, respectively. The high-frequency filter's measured operating frequency range is 4830-4940 MHz, with a 3-dB bandwidth of 110 MHz (2.3% relative bandwidth). The measured insertion loss and return loss are 0.43 dB and 15 dB, respectively. The high-frequency and low-frequency out-of-band rejection are 37 dB at 6 GHz and 81 dB at 0.1 GHz, respectively. Furthermore, the measured isolation between the high- and low-frequency ports is better than 54 dB. Due to manufacturing errors, the test results for both frequency bands are shifted toward the high frequency, which can be fine-tuned by adjusting the tuning screws. The results show that the dual-band 5G combiner proposed in this invention is feasible.

[0073] The measured results show that the overall size of the combiner is ( : waveguide wavelength at 3.40 GHz).

[0074] Measurements show that the passband insertion loss of the single-cavity quad-mode filter and the single-cavity dual-mode filter is 0.43dB and 0.25dB, respectively. The return loss of both filters is better than 15dB. The isolation of the combiner is better than 54dB in the 0.1-6GHz frequency band. The measured results are highly consistent with the simulation results.

[0075] The present application also provides a vehicle, including the above-mentioned combiner, wherein the above-mentioned combiner is specifically applied to the 5G radio frequency front-end system of the vehicle.

[0076] In the vehicle 5G RF front-end system, the single-cavity multi-mode combiner uses an innovative single-cavity multi-resonance mode design. Under the premise of strictly maintaining the dual-band performance of 3320-3660MHz and 4830-4940MHz (isolation > 54dB, insertion loss 0.25 / 0.43dB), the number of cavities in the first filter BPF1 and the second filter BPF2 is reduced to one-fourth and one-half of the original, effectively reducing the required physical space and realizing the miniaturization of the equipment. Compared with microstrip combiners, cavity-structured combiners have the advantages of high power capacity and low insertion loss. Therefore, the combiner based on the single-cavity multi-mode filter in this application not only has the characteristics of high power capacity and low insertion loss of the cavity, but also has the advantages of fewer cavities and smaller physical size.

[0077] Furthermore, by controlling these resonant modes of the single-cavity quad-mode filter, a compact filter with wide bandwidth and multi-band characteristics can be designed. This design provides a novel miniaturized dual-band 5G combiner solution for multi-band communication systems in smart cars.

[0078] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0079] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0080] It should also be noted that, in this document, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are for the purpose of facilitating the description of the present invention and simplifying the description, rather than indicating or implying that the devices or components referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, relational terms such as "first" and "second" are used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any actual relationship or order between these entities or operations, nor should they be understood as indicating or implying relative importance. Moreover, the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device comprising a series of elements does not include those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or terminal device comprising the element.

[0081] The technical solutions provided by the present invention have been described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is intended only to facilitate understanding of the present invention, and the contents of this specification should not be construed as limiting the present invention. Furthermore, those skilled in the art will appreciate that various modifications may be made to the specific implementation methods and scope of application according to the present invention. It is not necessary and impossible to exhaustively enumerate all implementation methods herein, and any obvious variations or modifications derived therefrom remain within the scope of protection of the present invention.

Claims

1. A combiner, characterized in that: include: A first filter and a second filter operating in different frequency bands; a microstrip filter power splitter cascaded with the first filter and the second filter; The microstrip filter power splitter combines or splits the signal of the first filter and the signal of the second filter; The first filter and the second filter are single-cavity multi-mode filters.

2. The combiner according to claim 1, wherein: The single-cavity multimode filter comprises: The housing has a cavity; At least two resonant columns are disposed in the cavity of the housing; an input coupling port and an output coupling port; an input feed probe and an output feed probe; The input feeding probe is electrically connected to the input coupling port and to one of the resonant columns, and is used to transmit the signal from the input coupling port to the resonant column; The output feeding probe is electrically connected to the output coupling port and to another resonant column, and is used to transmit the signal from the resonant column to the output coupling port.

3. The combiner according to claim 2, wherein: The top of each resonant column is provided with a coupling enhancement structure extending toward the center of the cavity, for enhancing the electromagnetic coupling between the resonant columns.

4. The combiner according to claim 2 or 3, characterized in that: The single-cavity multimode filter further comprises: at least one tuning element, for adjusting the resonant frequency of each of the resonant columns; At least one coupling adjustment element, used to adjust the coupling strength between the resonant columns; At least one tuning element and at least one coupling element are mounted on the cover plate of the housing.

5. The combiner according to claim 4, characterized in that: The first filter is a single-cavity four-mode filter, and the number of the resonant columns is four; A coupling element is provided between two adjacent resonant columns, and a coupling element is provided at the center of a plurality of resonant columns; Among them, the single-cavity four-mode filter has four different resonant modes; the first resonant mode has four magnetic rings in different directions; the fourth resonant mode produces a large magnetic ring; the first resonant mode and the fourth resonant mode are a pair of differential modes; the second resonant mode and the third resonant mode are a pair of degenerate modes.

6. The combiner according to claim 5, characterized in that: The number of the tuning elements is the same as the number of the resonant columns, and a tuning element is provided directly above each of the resonant columns for independently adjusting the resonant frequency of each resonant column.

7. The combiner according to claim 2 or 3, characterized in that: The single-cavity multi-mode filter is a single-cavity dual-mode filter. There are two resonant columns, and the single-cavity dual-mode filter has two different resonant modes.

8. The combiner according to claim 7, characterized in that: A 180° phase difference is introduced between the input coupling port and the output coupling port of the single-cavity dual-mode filter to optimize the frequency response.

9. The combiner according to claim 1, wherein: The operating frequency band of the first filter is between 3320-3660 MHz, and the frequency band of the second filter is between 4830-4940 MHz.

10. The combiner according to claim 1, wherein: The microstrip filter power divider comprises: a first port, a second port, and a third port; an isolation resistor connected between the second port and the third port; a first transmission line and a first open line connected to the first port and the second port; a second transmission line and a second open line connected to the first port and the third port; The second port is electrically connected to the first filter, and the third port is electrically connected to the second filter.

11. The combiner according to claim 1, wherein: The first filter and the second filter are electrically connected to the microstrip filter power divider using a 50Ω coaxial cable.

12. A vehicle, characterized in that: The combiner comprises the combiner according to any one of claims 1 to 11.

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