Broadband integrated low-profile phased array integrated network

Abstract

The invention discloses a broadband integrated low-profile phased array integrated network. A monitoring network is located right above an aperture transformation network. The aperture transformation network is of a microstrip line or strip line structure and comprises a first lower-layer signal feeder line, a first middle-layer microwave substrate and a first upper-layer metal floor which are sequentially stacked from bottom to top. The main body part of the monitoring network adopts a substrate integrated waveguide structure, and comprises a substrate integrated waveguide coupling power divider, a broadband gradient impedance matching structure, a microstrip feeder line and a terminal absorption load. According to the invention, the aperture transformation network and the monitoring network are integrated through the multilayer microwave plate vertical interconnection processing technology, the number of hardware equipment is reduced, the spatial layout is optimized, the integration level of the system is improved, and the system has the characteristics of miniaturization, light weight and easy processing. Furthermore, a substrate integrated waveguide coupling power divider is adopted, amplitude and phase data of signals in each channel can be extracted independently, electromagnetic interference of the external environment can be shielded through a closed structure, and calibration precision and consistency of monitoring signals between the channels are improved.

Description

Technical Field

[0001] This invention belongs to the field of phased array network technology, and particularly relates to a broadband integrated low-profile phased array network. Background Technology

[0002] With the rapid iteration of active phased array radar technology, phased array antenna systems are gradually developing towards digitalization, high power, multi-functionality, and high integration.

[0003] When thousands of phased array channels operate for extended periods, changes in the operating conditions of active components such as T / R modules within the channels cause alterations in signal amplitude and phase, leading to beam distortion and pointing deviation in the phased array antenna system, thus degrading system performance. Therefore, real-time monitoring and calibration of signal amplitude and phase in each channel of the phased array system are essential to ensure its performance. Currently, commonly used phased array monitoring methods are divided into external monitoring and internal monitoring. External monitoring typically requires the introduction of additional calibration antenna elements; its calibration accuracy is significantly affected by the external environment, resulting in poor amplitude and phase calibration. Internal monitoring generally involves the introduction of additional monitoring devices with coupling capabilities; however, it requires a large amount of hardware and involves a complex monitoring network, typically only suitable for subarray-level monitoring, resulting in lower calibration accuracy and higher costs.

[0004] Furthermore, to facilitate the integrated layout of other components within the phased array system, the T / R (Transmission / Relocation) modules are arranged more compactly, with their port spacing often smaller than the antenna element spacing. Therefore, an aperture conversion network must be introduced to achieve equal-amplitude and in-phase transmission of signals from each channel between the antenna elements and the T / R modules. Traditionally, the monitoring network and aperture conversion network of a phased array antenna system are independent. For highly integrated phased array antenna systems, with their numerous and extremely complex components and limited space, using independent monitoring and aperture conversion networks would lead to difficulties in space layout and significantly increase the system design complexity and cost. Summary of the Invention

[0005] The technical objective of this invention is to provide a broadband integrated low-profile phased array network to solve the problems of poor monitoring effect and low accuracy of phased array channels.

[0006] To solve the above problems, the technical solution of the present invention is as follows: A broadband integrated low-profile phased array network includes: A caliber transformation network and a monitoring network are used, with the monitoring network located directly above the caliber transformation network. The aperture conversion network adopts a microstrip or stripline structure, including a first lower layer signal feed line, a first intermediate layer microwave substrate, and a first upper layer metal ground plane stacked from bottom to top; the first lower layer signal feed line is composed of several metal lines, the number of which is consistent with the number of phased array channels; several coupling holes are opened on the first upper layer metal ground plane, and the coupling holes correspond one-to-one with the metal lines. The main body of the monitoring network adopts a substrate integrated waveguide structure, including: a substrate integrated waveguide coupled power divider, a broadband tapered impedance matching structure, a microstrip feeder, and a terminal absorption load; the top of the substrate integrated waveguide coupled power divider is a second upper metal ground plane, the broadband tapered impedance matching structure is located on both sides of the second upper metal ground plane, the microstrip feeder is located on both sides of the broadband tapered impedance matching structure and connected to the corresponding broadband tapered impedance matching structure, wherein the microstrip feeder on one side is connected to the main monitoring port, and the microstrip feeder on the other side is connected to the terminal absorption load.

[0007] The two ends of the integrated network can be connected to the phased array antenna unit and the T / R component respectively via RF connectors.

[0008] The first lower-layer signal feeder is a set of metal lines of equal length, which realizes the equal amplitude and in-phase transmission of signals in each channel.

[0009] The substrate integrated waveguide coupled power divider also includes a second intermediate microwave substrate and a second lower metal ground plane, which are stacked sequentially from bottom to top. Among them, two sets of metallized through holes are respectively provided on both sides along the length direction of the second intermediate layer microwave substrate; The second lower metal floor has coupling holes, and the second lower metal floor and its coupling holes are set in a manner corresponding to the first upper metal floor and its coupling holes.

[0010] The second lower metal floor is stacked with the first upper metal floor, or the second lower metal floor and the first upper metal floor share the same board.

[0011] Among them, the broadband gradient impedance matching structure is set on both sides of the second upper metal floor, and its structure is a transition structure such as trapezoidal or logarithmic curve.

[0012] In this structure, the width of one end of the broadband tapered impedance matching structure is equal to the width of the microstrip feed line, while the width of the other end is less than or equal to the width of the second upper metal ground plane.

[0013] The microstrip feeder is connected to the terminal absorption load via soldering or an RF connector. The resistance of the terminal absorption load is equal to the resistance of the microstrip feeder connected to it.

[0014] The coupling amplitude of the monitoring network is adjusted by changing the position and diameter of the coupling hole.

[0015] The size of the integrated network can be adjusted according to actual design requirements to cover any number of phased array channels.

[0016] Because of the above technical solutions, this invention has the following advantages and positive effects compared with the prior art: This invention integrates the aperture conversion network and the monitoring network through multi-layer microwave board vertical interconnection processing technology, which reduces the amount of hardware equipment, optimizes the spatial layout, and improves the system integration. It features miniaturization, lightweight and easy processing. This invention employs a substrate-integrated waveguide-coupled power divider, which can independently extract the amplitude and phase data of the signal in each channel. Its closed structure can shield against electromagnetic interference from the external environment, thereby improving calibration accuracy and the consistency of monitoring signals between channels. The present invention can conveniently adjust the coupling amplitude of the monitoring network by adjusting the position and diameter of the coupling hole, which can adapt to the link requirements of systems of different sizes; The network size of this invention can be adjusted according to actual design requirements, covering any number of phased array channels. Attached Figure Description

[0017] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0018] Figure 1 This is a schematic diagram of the structure of a broadband integrated low-profile phased array integrated network according to the present invention; Figure 2 This is a schematic diagram of the aperture transformation network of the present invention; Figure 3 This is a schematic diagram of the monitoring network structure of the present invention; Figure 4 This is a three-dimensional exploded view of the present invention; Figure 5 The voltage standing wave ratio (VSWR) curves of ports p1 to p16 of this invention; Figure 6 The transmission coefficient amplitude curves of ports p17~p32 to p1~p16 in this invention; Figure 7 The transmission coefficient phase curves of ports p17~p32 to p1~p16 in this invention; Figure 8 The voltage standing wave ratio (VSWR) curve of the pC port of this invention; Figure 9This is the amplitude curve of the coupling coefficient from pC to ports p1~p16 of the present invention; Figure 10 This is the phase curve of the transmission coefficient from pC to p1~p16 ports of the present invention.

[0019] Explanation of reference numerals in the attached figures 1: Aperture conversion network; 11: First lower layer signal feed line; 12: First intermediate layer microwave substrate; 13: First upper layer metal ground plane; 14: Coupling hole; 2: Monitoring network; 21: Substrate integrated waveguide coupled power divider; 22: Broadband tapered impedance matching structure; 23: Microstrip feed line; 24: Termination absorption load; 211: Second lower layer metal ground plane; 212: Second intermediate layer microwave substrate; 213: Second upper layer metal ground plane; 214: Metallized via; 215: Coupling hole. Detailed Implementation

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0021] To keep the drawings concise, only the parts relevant to the invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of components with the same structure or function is shown schematically, or only one is labeled. In this document, "one" can mean not only "only one" but also "more than one".

[0022] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a broadband integrated low-profile phased array network proposed in this invention. The advantages and features of this invention will become clearer from the following description and claims.

[0023] See Figures 1 to 4 This embodiment provides a broadband integrated low-profile phased array network, such as... Figure 1 The diagram shown is a schematic representation of the overall structure of this embodiment, which includes: an aperture conversion network 1 and a monitoring network 2. Spatially, the monitoring network 2 is located directly above the aperture conversion network 1. This embodiment takes a broadband integrated low-profile phased array network operating in the X-band as an example, with a center frequency of 10 GHz, and lower and upper sidebands of 8 GHz and 12 GHz respectively, covering 16 phased array channels.

[0024] See Figure 2This is a schematic diagram of the overall structure of the aperture conversion network 1 in this embodiment. It adopts a microstrip or stripline structure, including a first lower-layer signal feed line 11, a first intermediate microwave substrate 12, and a first upper-layer metal ground plane 13 stacked sequentially from bottom to top. Specifically, the first lower-layer signal feed line 11 consists of sixteen metal lines, and the first upper-layer metal ground plane 13 has sixteen coupling holes 14, with each coupling hole 14 corresponding to one of the metal lines. Figure 2 For example, a total of thirty-two external interfaces (p1~p32) are provided, namely: sixteen T / R component ports (p1~p16) and sixteen antenna ports (p17~p32), corresponding to sixteen phased array channels. That is, the first lower layer signal feed line 11 is composed of sixteen metal lines of equal length, realizing the equal amplitude and in-phase transmission of sixteen signals between the antenna and the T / R component. Furthermore, sixteen coupling holes 14 with a diameter of 1.6mm on the first upper layer metal ground plane 13 correspond one-to-one with the above sixteen metal lines.

[0025] See Figure 3 This is a schematic diagram of the overall structure of the monitoring network 2 in this embodiment. Its main body adopts a substrate integrated waveguide structure, including: a substrate integrated waveguide coupled power divider 21, a broadband tapered impedance matching structure 22, a microstrip feeder 23, and a terminating absorption load 24. The top of the substrate integrated waveguide coupled power divider 21 is a second upper metal ground plane 213. The broadband tapered impedance matching structure 22 is located on both sides of the second upper metal ground plane 213. The microstrip feeder 23 is located on both sides of the broadband tapered impedance matching structure 22 and connected to the corresponding broadband tapered impedance matching structure 22. The microstrip feeder 23 on the left is connected to the main monitoring port, which can extract amplitude and phase data from the sixteen phased array channels. The microstrip feeder 23 on the right is connected to the terminating absorption load 24, which can absorb excess electromagnetic energy and ensure good impedance matching performance of the circuit. Furthermore, the broadband tapered impedance matching structure 22 is located on both sides of the second upper metal ground plane 213, and its structure is trapezoidal or logarithmic curve. Figure 3 As shown, the broadband tapered impedance matching structure 22 adopts a trapezoidal structure. The shorter side of the trapezoid is 1.5 mm long (the same width as the microstrip feed line 23), the longer side is 8 mm long (less than the width of the second upper metal ground plane 213), and the height is 12 mm. This structure enables impedance matching between the substrate-integrated waveguide-coupled power divider 21 and the 50Ω microstrip feed line 23 throughout the entire operating frequency band (8~12 GHz). Furthermore, the microstrip feed line 23 is connected to the terminating absorption load 24 via soldering or an RF connector. The resistance of the terminating absorption load 24 is equal to the resistance of the connected microstrip feed line 23, both being 50Ω.

[0026] See Figure 4In this embodiment, the substrate-integrated waveguide-coupled power divider 21 further includes a second intermediate microwave substrate 212 and a second lower metal ground plane 211, which are stacked sequentially from bottom to top. Figure 4 As shown, the second lower metal ground plane 211 has sixteen coupling holes 215. The second lower metal ground plane 211 is stacked with the first upper metal ground plane 13, or the second lower metal ground plane 211 shares the same structure with the first upper metal ground plane 13 of the aperture conversion network 1 and its sixteen coupling holes 14. Further, along the length of the second intermediate microwave substrate 212, two sets of metallized vias 214 are respectively provided on both sides. Specifically, the width of the second upper metal ground plane 213 (the distance between the two sets of metallized vias 214) is 15mm, and its cutoff frequency is approximately 6.5GHz, which is less than the lower sideband of the operating frequency band of 8GHz, meeting the requirements for substrate integrated waveguide operation. The diameter of the metallized via 214 is 0.5mm, and the distance between adjacent vias is 0.9mm. The diameter of the coupling hole 215 and its distance from the lower metallized through hole 214 affect the amount of electromagnetic energy coupling, which determines the transmission coefficient amplitude of the signal from the first lower-level signal feed line 11 of the aperture conversion network 1 to the monitoring port (pC). In this embodiment, the diameter of the coupling hole is 1.6 mm and the distance between it and the lower metallized through hole 214 is 2.8 mm, which can achieve a coupling amount of -40 dB ± 3 dB.

[0027] The effectiveness of this embodiment can be further illustrated by the following simulation: Figures 5-7 To demonstrate the simulation performance of aperture transformation network 1 in this embodiment, Figures 8-9 The simulation performance of monitoring network 2 in this embodiment is shown.

[0028] like Figure 5 As shown, the signal feeder ports (p1~p16) of the aperture conversion network 1 in this embodiment have a VSWR < 1.2 in the 8~12GHz operating frequency band, indicating good full-band matching.

[0029] like Figure 6 As shown, the transmission coefficient amplitude of the aperture conversion network from ports 1p17 to p32 to p1 to p16 in this embodiment fluctuates within the operating frequency band of 8 to 12 GHz in the range of -0.37 to -0.25 dB, that is: insertion loss < 0.4 dB, and amplitude consistency between channels < 0.1 dB, indicating that this embodiment has low loss and equal amplitude aperture conversion function.

[0030] like Figure 7As shown, the phase of the transmission coefficients of the aperture conversion network from ports 1p17 to p32 to p1 to p16 in this embodiment is consistent with the channel phase within the 8 to 12 GHz operating frequency band by < ±1°, indicating that this embodiment has an equal-phase aperture conversion function.

[0031] like Figure 8 As shown, the monitoring port (pC) in this embodiment has a VSWR of <1.6 in the 8~12GHz operating frequency band, indicating good matching across the entire frequency band.

[0032] like Figure 9 As shown, the amplitude of the coupling coefficient from the monitoring port (pC) to the signal feeder port (p1~p16) in this embodiment fluctuates within the operating frequency band of 8~12GHz by -40±3dB. That is, the signal amplitudes extracted from the 16 channels from the monitoring port (pC) are within the range of -40±3dB, and the amplitude consistency between channels is <±2.2dB, indicating that this embodiment has a high-precision amplitude monitoring function.

[0033] like Figure 10 As shown, the transmission coefficient phase from the monitoring port (pC) to the signal feeder port (p1~p16) in this embodiment can be independently extracted at the channel level within the working frequency band of 8~12GHz, indicating that this embodiment has a high-precision phase monitoring function.

[0034] It is evident that integrating the aperture conversion network 1 and the monitoring network 2 through multi-layer microwave board vertical interconnection processing technology reduces the amount of hardware equipment, optimizes the spatial layout of the system, reduces processing costs, and provides excellent electrical performance characteristics such as low loss and high precision.

[0035] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A broadband integrated low-profile phased array network, characterized in that, include: A caliber conversion network and a monitoring network, wherein the monitoring network is located directly above the caliber conversion network; The aperture conversion network adopts a microstrip line or stripline structure, including a first lower layer signal feed line, a first intermediate layer microwave substrate, and a first upper layer metal ground plane stacked from bottom to top; the first lower layer signal feed line is composed of a number of metal lines, the number of which is consistent with the number of phased array channels; a number of coupling holes are opened on the first upper layer metal ground plane, and the coupling holes correspond one-to-one with the metal lines. The main body of the monitoring network adopts a substrate integrated waveguide structure, including: a substrate integrated waveguide coupled power divider, a broadband tapered impedance matching structure, a microstrip feeder, and a terminating absorption load; the top of the substrate integrated waveguide coupled power divider is a second upper metal ground plane, the broadband tapered impedance matching structure is disposed on both sides of the second upper metal ground plane, the microstrip feeder is disposed on both sides of the broadband tapered impedance matching structure and connected to the corresponding broadband tapered impedance matching structure, wherein one side of the microstrip feeder is connected to the main monitoring port, and the other side of the microstrip feeder is connected to the terminating absorption load.

2. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The two ends of the integrated network can be connected to the phased array antenna unit and the T / R component respectively via radio frequency connectors.

3. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The first lower-layer signal feeder is a set of metal lines of equal length, which realizes equal amplitude and in-phase transmission of signals in each channel.

4. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The substrate integrated waveguide coupled power divider also includes a second intermediate microwave substrate and a second lower metal ground plane, wherein the second lower metal ground plane, the second intermediate microwave substrate and the second upper metal ground plane are stacked sequentially from bottom to top. Among them, two sets of metallized through holes are respectively provided on both sides along the length direction of the second intermediate layer microwave substrate; The second lower metal floor has a coupling hole, and the second lower metal floor and its coupling hole are provided in a manner corresponding to the first upper metal floor and its coupling hole.

5. The broadband integrated low-profile phased array integrated network according to claim 4, characterized in that, The second lower metal floor is stacked with the first upper metal floor, or the second lower metal floor and the first upper metal floor share the same board.

6. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The broadband gradient impedance matching structure is located on both sides of the second upper metal floor, and its structure is a transition structure such as a trapezoidal or logarithmic curve.

7. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The width of one end of the broadband tapered impedance matching structure is equal to the width of the microstrip feed line, and the width of the other end is less than or equal to the width of the second upper metal ground plane.

8. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The microstrip feed line is connected to the terminal absorption load via soldering or an RF connector, and the resistance of the terminal absorption load is equal to the resistance of the microstrip feed line connected to it.

9. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The coupling amplitude of the monitoring network can be adjusted by changing the position and diameter of the coupling hole.

10. The broadband integrated low-profile phased array integrated network according to claim 1, characterized in that, The size of the integrated network can be adjusted according to actual design requirements to cover any number of phased array channels.

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