Local oscillator power division network for vehicle-mounted radar
By using a combination of vertical interconnect vias and stripline Gysel power splitters in 4D mmWave radar, stray radiation and transmission loss problems near the radar local oscillator frequency are solved, and a high isolation power split network is achieved, reducing the power splitting effect. The cost and simplifies the antenna array design.
Patent Information
- Application Number
- CN202420062755.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-10
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-01-10
AI Technical Summary
The spurious radiation problem of existing 4D millimeter wave radar near the local oscillator frequency leads to increased costs and complex antenna array impacts, and has large transmission losses, making it difficult to achieve a high isolation power division network.
Using a local oscillator power division network including vertical interconnect vias and stripline Gysel power division devices, the conversion of the local oscillator from the grounded coplanar waveguide of the surface layer of the laminate to the sub-inner layer is achieved through vertical interconnect vias, and the belt is combined with the belt The Gysel power splitter performs power distribution to ensure no stray radiation and saves high-frequency and low-loss core plates.
It effectively avoids stray radiation exceeding the standard near 20GHz, saves the use of high-frequency and low-loss core boards, realizes high isolation power distribution and good transmission losses, and meets the stray testing standards of the country and the OEM.
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Figure CN222146553U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of automatic driving, and in particular to a local oscillator power division network for a vehicle-mounted radar. Background Art
[0002] With the rapid development of autonomous driving, 4D millimeter wave radar has gradually become a must-have in intelligent driving perception solutions due to its low cost and strong environmental adaptability. In order to obtain higher resolution and point cloud density, 4D millimeter wave radar needs to add more transceiver channels. The solution provided by the current mainstream 77GHz radar chip manufacturers is to cascade multiple radar chips. This solution requires the main chip to generate a 19GHz-20.25Ghz local oscillation signal, and use the transmission line power division network to synchronize the local oscillator signal delay between the cascaded chips to reduce frequency mismatch.
[0003] Whether the design and distribution of the local oscillator power splitter network are reasonable will affect the spurious radiation of the radar near the local oscillator frequency. The current common practice in the industry is to use the solution of converting the local oscillator line to the inner layer transmission line or adding an external shielding cover. The local oscillator line is generally chosen to go through the L3 layer on the inner layer, which is convenient for design and avoids layout interference with the antenna. However, this solution requires that the L1-L4 layers of the laminate are all high-frequency and low-loss core boards and prepregs, which will increase the cost. For the four-chip cascade solution, the power divider is a necessary passive module. If you want the power divider network to achieve perfect matching and high isolation between the output ports, you need to use a passive Wilkinson power divider with an isolation resistor. If the local oscillator transmission line on the inner layer wants high isolation between the output ports, it is generally transferred to the surface layer using interconnection vias, and then connected to the Wilkinson power divider. The output port is then moved to the inner layer through vertical interconnection vias. This method increases the transmission loss of the local oscillator line, and the surface power divider also requires an external shielding cover. Another solution is to run the local oscillator line on the surface and use a shielding cover to completely cover it. This requires an area that covers the entire local oscillator line, which affects some complex antenna arrays.
[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Utility Model Content
[0005] The purpose of the utility model is to solve the technical problems existing in the background technology, and for this purpose, a local oscillator power division network for vehicle-mounted radar is provided.
[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0007] A local oscillator power splitter network for a vehicle-mounted radar, comprising a first vertical interconnection via, a second vertical interconnection via, a third vertical interconnection via, a first strip transmission line, a second strip transmission line, a third strip transmission line and a strip line Gysel power splitter;
[0008] The stripline Gysel power divider comprises an input port, a first output port and a second output port, wherein the input port is connected to the first stripline transmission line, the first output port is connected to the third stripline transmission line, and the second output port is connected to the second stripline transmission line;
[0009] The first strip transmission line is connected to the first vertical interconnection via, the second strip transmission line is connected to the second vertical interconnection via, and the third strip transmission line is connected to the third vertical interconnection via.
[0010] The following is a technical solution further defined by the present invention, wherein the first vertical interconnection via, the second vertical interconnection via, and the third vertical interconnection via are all realized by etching copper foil and drilling holes on the laminate, the laminate comprises a dielectric substrate, a prepreg, and a laminated sub-board, the upper and lower surfaces of the dielectric substrate are copper-clad, the laminated sub-board is a multi-layer laminated sub-board, and the laminated sub-board and the dielectric substrate are mixed and pressed through the prepreg;
[0011] A microstrip line is etched on the upper surface of the dielectric substrate, a microstrip line avoidance area is formed between the microstrip line and the copper foil on the upper surface of the dielectric substrate, the copper foils on the upper and lower surfaces of the dielectric substrate are connected with metal grounding holes, and the microstrip line is connected with a strip transition line through a signal hole.
[0012] The copper foils on the upper and lower surfaces of the dielectric substrate and the upper surface of the laminated sub-board are connected with grounding holes, and the grounding holes penetrate the dielectric substrate and the prepreg;
[0013] A stripline is etched on the lower surface of the dielectric substrate, a stripline avoidance zone is formed between the stripline and the copper foil on the lower surface of the dielectric substrate, and the striplines are connected to the stripline transition lines, and a stripline avoidance zone is formed between the stripline and the copper foil on the lower surface of the dielectric substrate.
[0014] The following is a technical solution further defined by the present utility model, wherein the first strip transmission line, the second strip transmission line, and the third strip transmission line all include a strip line, a strip line avoidance area, and a grounding hole;
[0015] The strip line, the strip line avoidance area and the grounding hole transmit energy through the electric field bound in the dielectric substrate and the prepreg to form a strip transmission line.
[0016] The following is a technical solution further defined by the present invention, wherein the electrical lengths of the second strip transmission line and the third strip transmission line are the same.
[0017] The following is a technical solution further defined by the present invention, wherein the stripline Gysel power divider comprises a first stripline transition line of the power divider, a second stripline transition line of the power divider, a third stripline transition line of the power divider, a fourth stripline transition line of the power divider and a fifth stripline transition line of the power divider connected in sequence;
[0018] The electrical length of the second strip transition line of the power divider is 90 degrees, and the corresponding characteristic impedance is 1.414 times that of the first strip transmission line. The electrical length of the third strip transition line of the power divider is 90 degrees, and the corresponding characteristic impedance is the same as that of the first strip transmission line. The electrical length of the fourth strip transition line of the power divider is 180 degrees, and the corresponding characteristic impedance is 0.354 times that of the first strip transmission line.
[0019] The following is a technical solution further defined by the present utility model, wherein the stripline Gysel power divider further comprises a power divider vertical interconnection via, and the power divider vertical interconnection via and the first vertical interconnection via have the same structure;
[0020] The vertical interconnection via of the power divider is connected to the grounded coplanar waveguide, and the characteristic impedance corresponding to the grounded coplanar waveguide is the same as that of the first strip transmission line;
[0021] The end of the grounded coplanar waveguide is connected to a grounded isolation resistor, and the resistance of the grounded isolation resistor is the same as the characteristic impedance of the first strip transmission line.
[0022] Compared with the prior art, the utility model has the following technical effects:
[0023] 1. The utility model realizes the conversion of the local oscillator line from the grounded coplanar waveguide on the surface layer of the laminate to the stripline on the sub-inner layer through vertical interconnected vias. Compared with the grounded coplanar waveguide directly on the surface layer of the laminate, the stripline on the sub-inner layer only binds the electromagnetic energy between the L1 layer and the L3 layer, and the stray radiation to the free space can be almost ignored, avoiding the excessive stray radiation near 20GHz, so that it can pass the national and OEM stray test standards; in addition, the vertical interconnected vias only need to occupy the L1-L3 layers of the laminate. Since the local oscillator line transmits the local oscillator signal of 19GHz-20.25Ghz, only the high-frequency and low-loss core board of the L1-L2 layer and the high-frequency and low-loss prepreg of the L2-L3 layer are needed. Compared with the conventional solution of occupying the L1-L4 layer, a high-frequency and low-loss core board is saved;
[0024] 2. The utility model is provided with a stripline Gysel power divider, which can ensure that the transmission line completes high-isolation power distribution without stray radiation and also maintains good transmission loss.
[0025] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0027] Figure 1 It is a top view of the local oscillator line power division network of the vehicle-mounted radar of the utility model;
[0028] Figure 2 (a) is a side view of the vertical interconnect via of the utility model;
[0029] Figure 2 (b) is a three-dimensional view of the vertical interconnect via of the utility model;
[0030] Figure 3 It is a three-dimensional view of the stripline Gysel power divider structure of the utility model;
[0031] Figure 4 It is a simulation diagram of the port reflection coefficient of the local oscillator line power division network of the utility model;
[0032] Figure 5 It is a port insertion loss simulation diagram of the local oscillator line power division network of the utility model;
[0033] Figure 6 This is a simulation diagram of the output port isolation of the local oscillator line power division network of the utility model;
[0034] Figure 7 It is a simulation diagram of the phase delay of the output port of the local oscillator line power division network of the utility model;
[0035] Figure 8 It is the far-field radiation gain diagram of the local oscillator line power division network of the utility model.
[0036] Reference numerals: 11, first vertical interconnection via; 12, second vertical interconnection via; 13, third vertical interconnection via;
[0037] 111, dielectric substrate; 112, prepreg; 113, laminated sub-board;
[0038] 121. Microstrip line; 122. Microstrip line avoidance area; 123. Metal grounding hole;
[0039] 131, signal hole; 132, ground hole; 133, strip transition line; 134, strip line; 135, strip line avoidance area;
[0040] 21. a first strip transmission line; 22. a second strip transmission line; 23. a third strip transmission line;
[0041] 3. Stripline Gysel power divider;
[0042] 311, first strip transition line of power divider; 312, second strip transition line of power divider; 313, third strip transition line of power divider; 314, fourth strip transition line of power divider; 315, grounding hole of power divider; 316, fifth strip transition line of power divider; 32, vertical interconnection via of power divider; 331, grounded coplanar waveguide; 332, ground isolation resistor; 34, input port; 35, first output port; 36, second output port DETAILED DESCRIPTION
[0043] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.
[0044] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0045] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0046] In the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.
[0047] like Figure 1-3 As shown, a local oscillator power division network for a vehicle-mounted radar is provided, which is composed of a first vertical interconnection via 11, a second vertical interconnection via 12, a third vertical interconnection via 13, a first strip transmission line 21, a second strip transmission line 22, a third strip transmission line 23 and a stripline Gysel power divider 3.
[0048] The stripline Gysel power divider 3 comprises an input port 34 , a first output port 35 and a second output port 36 , wherein the input port 34 is connected to the first stripline transmission line 21 , the first output port 35 is connected to the third stripline transmission line 23 , and the second output port 36 is connected to the second stripline transmission line 22 .
[0049] The first strip transmission line 21 is connected to the first vertical interconnection via 11 , the second strip transmission line 22 is connected to the second vertical interconnection via 12 , and the third strip transmission line 23 is connected to the third vertical interconnection via 13 .
[0050] There are three vertical interconnection vias, namely the first vertical interconnection via 11, the second vertical interconnection via 12, and the third vertical interconnection via 13, and the structures of the three vertical interconnection vias are the same. The first vertical interconnection via 11, the second vertical interconnection via 12, and the third vertical interconnection via 13 are all realized by etching copper foil and drilling holes on the laminate. The laminate includes a dielectric substrate 111, a prepreg 112, and a laminated sub-board 113. The upper and lower surfaces of the dielectric substrate 111 are clad with copper; the laminated sub-board 113 is a multi-layer laminated sub-board, and the material is a plate material suitable for low-frequency signal lines and power lines; the dielectric substrate 111 and the prepreg 112 are high-frequency and low-loss materials. The laminated sub-board 113 and the dielectric substrate 111 are mixed and pressed through the prepreg 112.
[0051] A microstrip line 121 is etched on the upper surface of the dielectric substrate 111, and a microstrip line avoidance area 122 is formed between the microstrip line 121 and the copper foil on the upper surface of the dielectric substrate 111. A row of metal grounding holes 123 is added next to the microstrip line 121 to form a grounded coplanar waveguide structure. The copper foils on the upper and lower surfaces of the dielectric substrate 111 are connected with the metal grounding holes 123. Energy is transmitted by the electric field bound in the dielectric substrate 111 and the free space, thereby reducing the transmission loss of the microstrip line 121.
[0052] The signal hole 131 connects the microstrip line 121 and the strip transition line 133, that is, the microstrip line 121 is connected to the strip transition line 133 through the signal hole 131; there are circular hole disks of specific sizes at the two connections, and the circular hole disks are used to ensure the connection between the signal hole 131 and the microstrip line 121 and the strip transition line 133. There is an avoidance area of specific sizes between the two hole disks and the grounding copper foil of the same layer.
[0053] The copper foils on the upper and lower surfaces of the dielectric substrate 111 and the upper surface of the laminated sub-board 113 are connected with grounding holes 132, and the grounding holes 132 penetrate the dielectric substrate 111 and the prepreg 112, and are used to connect the copper foils on the upper and lower surfaces of the dielectric substrate 111 and the upper surface of the laminated sub-board 113. The grounding holes 132 are controlled depth holes realized by a mechanical drill bit after the laminate is mixed and pressed.
[0054] A strip transition line 133 is etched on the lower surface of the dielectric substrate 111, and a strip line avoidance area 135 is formed between the strip transition line 133 and the copper foil on the lower surface of the dielectric substrate 111. The farther the avoidance area is from the signal hole 131, the greater the avoidance distance. The length and width of the strip transition line 133 can be adjusted to allow the vertical interconnection via to have good transmission loss and impedance matching, and the situation where the line width is the same as the strip line 134 is not excluded.
[0055] The stripline 134 is connected to the stripline transition line 133 , and a stripline avoidance area 135 is formed between the stripline 134 and the copper foil on the lower surface of the dielectric substrate 111 .
[0056] The first strip transmission line 21, the second strip transmission line 22, and the third strip transmission line 23 all include a strip line 134, a strip line avoidance area 135, and a grounding hole 132. The strip line 134, the strip line avoidance area 135, and the grounding hole 132 transmit energy through the electric field bound in the dielectric substrate 111 and the prepreg 112 to form a strip transmission line.
[0057] The stripline Gysel power divider 3 is a three-port network with bilateral symmetry in structure, and comprises three ports, namely an input port 34, a first output port 35 and a second output port 36, wherein the output powers of the first output port 35 and the second output port 36 are exactly the same.
[0058] The stripline Gysel power divider 3 comprises a first stripline transition line 311 , a second stripline transition line 312 , a third stripline transition line 313 , a fourth stripline transition line 314 and a fifth stripline transition line 316 which are connected in sequence.
[0059] The length and width of the first strip transition line 311 of the power divider can be adjusted to allow the stripline Gysel power divider 3 to have good transmission loss and impedance matching. The electrical length of the second strip transition line 312 of the power divider is 90 degrees, and the corresponding characteristic impedance is 1.414 times that of the first strip transmission line 21. The electrical length of the third strip transition line 313 of the power divider is 90 degrees, and the corresponding characteristic impedance is the same as the first strip transmission line 21. The electrical length of the fourth strip transition line 314 of the power divider is 180 degrees, and the corresponding characteristic impedance is 0.354 times that of the first strip transmission line 21. The fifth strip transition line 316 of the power divider can be of any length, and is adjusted according to the actual layout, and the corresponding characteristic impedance is the same as the first strip transmission line 21. It should be noted that the corresponding characteristic impedances of the first strip transmission line 21, the second strip transmission line 22 and the third strip transmission line 23 are the same.
[0060] The stripline Gysel power divider 3 also includes a power divider vertical interconnection via 32, which has the same structural design as the first vertical interconnection via 11. The power divider vertical interconnection via 32 is connected to a grounded coplanar waveguide 331, which can be of any length and can be adjusted according to the actual layout. The characteristic impedance corresponding to the grounded coplanar waveguide 331 is the same as that of the first stripline transmission line 21. The end of the grounded coplanar waveguide 331 is connected to a grounded isolation resistor 332, and the resistance value of the grounded isolation resistor 332 is the same as that of the characteristic impedance of the first stripline transmission line 21.
[0061] The electrical lengths of the second strip transmission line 22 and the third strip transmission line 23 are the same to ensure that the two output ports have the same delay. The first strip transmission line 21 is connected to the first vertical interconnection via 11 to receive the local oscillator signal from the input port 34. The second strip transmission line 22 and the third strip transmission line 23 are connected to the second vertical interconnection via 12 and the third vertical interconnection via 13 respectively, and the output port outputs the distributed local oscillator signal.
[0062] The three ports of the stripline Gysel power divider 3 are directly connected to the radar chip. The length of the grounded coplanar waveguide 331 between the three ports and the vertical interconnection vias should be as short as possible, and it needs to be covered by the chip shielding cover to ensure that no stray radiation is generated on the transmission line part of the laminate surface.
[0063] The vertical interconnected vias realize the conversion of the local oscillator line from the grounded coplanar waveguide 331 on the surface layer of the laminate to the stripline 134 on the sub-inner layer. Compared with the grounded coplanar waveguide 331 directly on the surface layer of the laminate, the stripline 134 on the sub-inner layer only confines the electromagnetic energy between the L1 layer and the L3 layer, and the stray radiation to the free space can be almost ignored, thus avoiding the stray radiation exceeding the standard near 20GHz, so that it can pass the national and OEM stray test standards.
[0064] In addition, the vertical interconnection vias only need to occupy the L1-L3 layers of the laminate. Since the local oscillator line transmits the local oscillator signal of 19GHz-20.25Ghz, only the high-frequency and low-loss core board of the L1-L2 layer and the high-frequency and low-loss semi-cured sheet 112 of the L2-L3 layer are needed. Compared with the conventional solution occupying the L1-L4 layer, a high-frequency and low-loss core board is saved.
[0065] The stripline Gysel power divider 3 can achieve proportional distribution of the local oscillator signal. In the cascade solution of 4 radar chips, the main chip needs to output four local oscillator signals with the same frequency and delay. The 1-to-2 proportional power divider is a necessary passive module. In order to achieve port matching for all ports and achieve a higher degree of isolation between output ports, the mainstream solution is to use a Wilkinson power divider with an isolation resistor. This solution is for the situation where the local oscillator line is always on the surface of the laminate. If the local oscillator line is on the inner layer, since the Wilkinson power divider has requirements for the position and distance of the welding isolation resistor, the general solution is to transfer the inner layer to the surface through vertical interconnection vias, and then connect the Wilkinson power divider module. However, this not only increases the transmission loss, but also requires a shielding cover to be added on the power divider module. The stripline Gysel power divider 3 adopted by the utility model is also a kind of Wilkinson power divider, which is characterized in that two external grounded isolation resistors 332 are required. The external distance will not affect the performance of the power divider, and the length can be adjusted arbitrarily. Therefore, it can be pulled apart to a suitable distance in the sub-inner layer, and then connected to the surface layer through vertical interconnection vias, and the isolation resistors are surface-mounted at the end. Without the need for complex processes such as buried resistors, the power distribution of the inner layer transmission line to complete full-port matching can be achieved. In addition, the partially grounded coplanar waveguide 331 and the two isolation resistors on the surface are to increase the isolation of the output port. The leaked electromagnetic energy is very small, and even if a shielding cover is not required, it will not affect the stray radiation. In summary, the stripline Gysel power divider 33 can ensure that the transmission line completes high-isolation power distribution without stray radiation, and also maintains a good transmission loss.
[0066] The local oscillator power distribution network model of the vehicle-mounted radar is as follows: Figure 1 As shown; the port reflection coefficient results obtained by simulation are as follows Figure 4As shown in Figure 2, it can be seen that the reflection coefficients of the three ports are all below -20dB, indicating that the vertical interconnection vias and the stripline Gysel power divider 3 have good port matching. The insertion loss results obtained by simulation are shown in Figure 2. Figure 5 As shown in the figure, it can be seen that the insertion loss from the input port 34 to the two output ports is about -4.5dB, and the power difference between the two output ports is within 0.2dB, which basically completes the proportional distribution of the local oscillator signal. Figure 6 As shown in the figure, we can see that the result is below -20dB, and the two output ports have good isolation. The phase delay simulation results of the output signals of the two output ports are as follows: Figure 7 As shown in Figure 1, we can see that the phase consistency difference is within 1 degree. The far-field radiation gain result of the entire local oscillator power splitter network is shown in Figure 1. Figure 8 As shown, only the three ports of the power division network, including the grounded coplanar waveguide 331 connected to the ports, are covered with a shielding cover, and the power divider is not provided with a shielding cover. The maximum far-field radiation gain is less than -45dB, and the stray radiation energy can be almost ignored.
[0067] The above is only a preferred embodiment of the utility model, and does not limit the utility model in any form. Any technician familiar with the field can make many possible changes and modifications to the technical solution of the utility model by using the above disclosed methods and technical contents without departing from the scope of the technical solution of the utility model, or modify it into an equivalent embodiment of equivalent changes. Therefore, all equivalent changes made according to the shape, structure and principle of the utility model without departing from the content of the technical solution of the utility model should be included in the protection scope of the utility model.
Claims
1. A local oscillator power division network for vehicle-mounted radar, It is characterized in that It comprises a first vertical interconnection via (11), a second vertical interconnection via (12), a third vertical interconnection via (13), a first strip transmission line (21), a second strip transmission line (22), a third strip transmission line (23) and a strip line Gysel power divider (3); The stripline Gysel power divider (3) comprises an input port (34), a first output port (35) and a second output port (36), wherein the input port (34) is connected to the first stripline transmission line (21), the first output port (35) is connected to the third stripline transmission line (23), and the second output port (36) is connected to the second stripline transmission line (22); The first strip transmission line (21) is connected to the first vertical interconnection via (11), the second strip transmission line (22) is connected to the second vertical interconnection via (12), and the third strip transmission line (23) is connected to the third vertical interconnection via (13).
2. A local oscillator power division network for vehicle-mounted radar according to claim 1, It is characterized in that The first vertical interconnection via (11), the second vertical interconnection via (12), and the third vertical interconnection via (13) are all realized by etching copper foil and drilling holes on the laminate, the laminate comprises a dielectric substrate (111), a prepreg (112), and a laminated sub-board (113), the upper and lower surfaces of the dielectric substrate (111) are copper-clad, the laminated sub-board (113) is a multi-layer laminated sub-board, and the laminated sub-board (113) and the dielectric substrate (111) are mixed and pressed through the prepreg (112); A microstrip line (121) is etched on the upper surface of the dielectric substrate (111); a microstrip line avoidance area (122) is formed between the microstrip line (121) and the copper foil on the upper surface of the dielectric substrate (111); the copper foils on the upper and lower surfaces of the dielectric substrate (111) are connected with metal grounding holes (123); the microstrip line (121) is connected with a strip transition line (133) through a signal hole (131); The copper foils on the upper and lower surfaces of the dielectric substrate (111) and the upper surface of the laminated sub-plate (113) are connected with grounding holes (132), and the grounding holes (132) connect the dielectric substrate (111) and the prepreg (112); A stripline transition line (133) is etched on the lower surface of the dielectric substrate (111); a stripline avoidance area (135) is formed between the stripline transition line (133) and the copper foil on the lower surface of the dielectric substrate (111); a stripline (134) is connected to the stripline transition line (133); and a stripline avoidance area (135) is formed between the stripline (134) and the copper foil on the lower surface of the dielectric substrate (111).
3. A local oscillator power division network for vehicle-mounted radar according to claim 2, It is characterized in that The first strip transmission line (21), the second strip transmission line (22), and the third strip transmission line (23) all include a strip line (134), a strip line avoidance area (135), and a grounding hole (132); The stripline (134), the stripline avoidance area (135) and the grounding hole (132) transmit energy through an electric field bounded in a dielectric substrate (111) and a prepreg sheet (112), thereby forming a stripline transmission line.
4. A local oscillator power division network for vehicle-mounted radar according to claim 3, It is characterized in that The electrical lengths of the second strip transmission line (22) and the third strip transmission line (23) are the same.
5. A local oscillator power division network for vehicle-mounted radar according to claim 1, It is characterized in that The stripline Gysel power divider (3) comprises a first stripline transition line (311) of the power divider, a second stripline transition line (312) of the power divider, a third stripline transition line (313) of the power divider, a fourth stripline transition line (314) of the power divider, and a fifth stripline transition line (316) of the power divider, which are connected in sequence; The electrical length of the second strip transition line (312) of the power divider is 90 degrees, and the corresponding characteristic impedance is 1.414 times that of the first strip transmission line (21); the electrical length of the third strip transition line (313) of the power divider is 90 degrees, and the corresponding characteristic impedance is the same as that of the first strip transmission line (21); the electrical length of the fourth strip transition line (314) of the power divider is 180 degrees, and the corresponding characteristic impedance is 0.354 times that of the first strip transmission line (21).
6. A local oscillator power division network for vehicle-mounted radar according to claim 5, It is characterized in that The stripline Gysel power divider (3) further comprises a power divider vertical interconnection via (32), and the power divider vertical interconnection via (32) has the same structure as the first vertical interconnection via (11); The power divider vertical interconnection via (32) is connected to the grounded coplanar waveguide (331), and the characteristic impedance corresponding to the grounded coplanar waveguide (331) is the same as that of the first strip transmission line (21); The end of the grounded coplanar waveguide (331) is connected to a grounded isolation resistor (332), and the resistance of the grounded isolation resistor (332) is the same as the characteristic impedance of the first strip transmission line (21).