Antenna feed and internal calibration circuit, active phased-array antenna and radar

Abstract

The utility model discloses an antenna feed and internal calibration circuit, an active phased-array antenna and a radar, and the circuit employs a strip line design and comprises a plurality of coupling power dividing units, a first combiner power divider, a first coupling common port, and a PCB. The plurality of coupling power division units, the first combiner power divider and the first coupling common port are integrated on the PCB; each coupling power division unit comprises a first directional coupler, a first equal-amplitude in-phase power divider and a first feed port; the first directional coupler is connected with the first feed port, the first equal-amplitude in-phase power divider and the load resistor; the fourth end of the first directional coupler of each coupling power division unit is connected with the first coupling common port through a first combiner power divider. According to the utility model, the strip lines are adopted for design, all parts are integrated in the same PCB, the structure is compact and simple, and the stability of sampling signals is enhanced.

Description

Technical Field

[0001] This utility model belongs to the field of antenna design technology, and particularly relates to an antenna feeding and internal calibration circuit, an active phased array antenna, and a radar. Background Technology

[0002] A phased array antenna consists of several antenna elements or subarrays and an active RF link at the back end. This RF link includes RF cables, attenuators, phase shifters, amplifiers, mixers, and other RF components. These components vary, making it difficult to guarantee amplitude and phase consistency between active channels during operation. This degrades the beam performance of the phased array antenna, severely impacting its usability. Therefore, the amplitude and phase characteristics of each channel must be monitored and calibrated during phased array antenna operation.

[0003] In existing technologies, internal calibration devices for monitoring and calibrating the amplitude and phase characteristics of each channel include switching matrices and traveling wave coupling networks. Switching matrices are complex to design and control, and traveling wave coupling networks, due to their structural limitations, are generally only used in waveguide array antennas. Utility Model Content

[0004] The purpose of this invention is to provide an antenna feeding and internal calibration circuit, an active phased array antenna, and a radar to solve the problems of complexity or limitations of traditional internal calibration equipment.

[0005] The present invention solves the above-mentioned technical problems through the following technical solution: an antenna feeding and internal calibration circuit, wherein the circuit adopts a stripline design and includes multiple coupling power dividers, a first combiner power divider, a first coupling common port and a PCB board, wherein the multiple coupling power dividers, the first combiner power divider and the first coupling common port are integrated on the PCB board;

[0006] Each of the coupling power dividers includes a first directional coupler, a first equal-amplitude and in-phase power divider, and a first feed port; the first end of the first directional coupler is connected to the first feed port, the second end of the first directional coupler is connected to the first equal-amplitude and in-phase power divider, and the third end of the first directional coupler is connected to the load resistor; the fourth end of the first directional coupler of each of the coupling power dividers is connected to the first coupling common port through a first combining power divider.

[0007] Furthermore, a first via wall is provided between two adjacent coupled power distribution units.

[0008] Furthermore, the plurality of the coupling power splitting units and the first combining power splitter are located on different layers of the PCB board.

[0009] Furthermore, the first equal-amplitude in-phase power divider adopts a design with two impedance transformation sections, and the two impedance transformation sections are connected to a coaxial structure.

[0010] Furthermore, each of the aforementioned coaxial structures includes a signal hole and a ground hole disposed around the signal hole.

[0011] Furthermore, the circuit also includes a second combiner power divider and a second coupling common port disposed on the PCB board; each coupling power divider unit further includes a second directional coupler, a second equal-amplitude and in-phase power divider, and a second power supply port; the first end of the second directional coupler is connected to the second power supply port, the second end of the second directional coupler is connected to the second equal-amplitude and in-phase power divider, and the third end of the second directional coupler is connected to the load resistor; the fourth end of the second directional coupler of each coupling power divider unit is connected to the second coupling common port through the second combiner power divider.

[0012] Furthermore, a second via wall is provided between the first directional coupler and the second directional coupler of each of the coupling power distribution units.

[0013] Furthermore, the first directional coupler and the second directional coupler of each of the coupling power distribution units are arranged in a rotationally symmetrical manner.

[0014] Based on the same concept, this utility model provides an active phased array antenna, which includes the antenna feeding and internal calibration circuits as described above.

[0015] Based on the same concept, this utility model provides a radar, which includes an active phased array antenna as described above.

[0016] Beneficial effects

[0017] Compared with the prior art, the advantages of this utility model are:

[0018] This invention samples the signal at the feed port using a directional coupler, then uses a combiner / divider to gather the sampled signal (or calibration signal) to the coupling common port, and finally connects the coupling common port to the radar. The use of the directional coupler allows external interference signals received from the antenna to be absorbed by the load, avoiding the influence of external interference signals on the sampled signal and enhancing the stability of the sampled signal.

[0019] This invention uses a stripline design, with all components integrated into the same PCB board, resulting in a compact and simple structure. At the same time, the stripline design forms a closed cavity, which reduces the impact of external factors on the overall sampling signal and further enhances the stability of the sampling signal. Attached Figure Description

[0020] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the antenna feeding and internal calibration circuit in an embodiment of this utility model;

[0022] Figure 2 This is a schematic diagram of the first combiner / divider and the second combiner / divider in an embodiment of this utility model;

[0023] Figure 3 This is a partial schematic diagram of the antenna feeding and internal calibration circuit in an embodiment of this utility model;

[0024] Figure 4 This is a layout diagram of the three coupled power distribution units in an embodiment of this utility model;

[0025] Figure 5 This is a schematic diagram of a single coupled power distribution unit in an embodiment of this utility model.

[0026] Explanation of reference numerals in the attached diagram: 1-Second combiner / divider, 2-First combiner / divider, 3-PCB board, 4-Coupled power divider unit, 41-First directional coupler, 411-Load resistor, 412-Through-board via, 42-First equal-amplitude in-phase power divider, 421-Impedance transformation section, 43-Second directional coupler, 44-Second equal-amplitude in-phase power divider, 45-First feed port, 46-Second feed port, 47-Signal hole, 48-Ground hole, 49-Second via wall, 5-Second coupling common port, 6-First coupling common port, 7-First via wall. Detailed Implementation

[0027] The technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0028] The technical solutions of this application will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0029] Example 1

[0030] Taking the antenna feeding and internal calibration circuit provided by this utility model, which includes 32 coupling power dividers 4, as an example, Figures 1 to 5 As shown, for the single-polarized antenna feeding and internal calibration circuit, the circuit includes 32 coupling power dividers 4, a first combiner power divider 2, a first coupling common port 6, and a PCB board 3. The 32 coupling power dividers 4, the first combiner power divider 2, and the first coupling common port 6 are integrated on the PCB board 3. Figure 5 As shown, each coupling power divider unit 4 includes a first directional coupler 41, a first equal-amplitude in-phase power divider 42, and a first feed port 45; the first end of the first directional coupler 41 is connected to the first feed port 45, the second end of the first directional coupler 41 is connected to the first equal-amplitude in-phase power divider 42, and the third end of the first directional coupler 41 is connected to the load resistor. Figure 3 As shown, the fourth end of the first directional coupler 41 of each coupling power splitting unit 4 is connected to the first coupling common port 6 through the first combiner power splitter 2. The number of first combiners power splitters 2 matches the number of coupling power splitting units 4. For 32 coupling power splitting units 4, the first combiner power splitter 2 has 32 channels, as shown. Figure 2 As shown.

[0031] The first directional coupler 41 samples the signal from the first feed port 45, then the first combiner power divider 2 gathers the sampled signal to the first coupling common port 6, and finally the first coupling common port 6 is connected to the radar for processing. This invention employs a stripline design, integrating all components onto the same PCB board 3, resulting in a compact and simple structure. Simultaneously, the stripline design forms a self-contained cavity, minimizing external influences on the sampled signal and further enhancing its stability. The first directional coupler 41 couples and samples the signal input from the first feed port 45 or the first coupling common port 6. The first directional coupler 41 ensures that external interference signals entering from the antenna end port are absorbed by the load resistor 411, avoiding the influence of external interference signals on the sampled signal and further enhancing its stability. Considering that the weights of the linear array antenna are symmetrically distributed when designing for low sidelobes, a first equal-amplitude in-phase power divider 42 is connected in series at the rear end of the first directional coupler 41 to divide the input signal into two equal parts. The weights of a linear array antenna refer to the parameters used to control the amplitude and phase of the transmitted or received signals of each antenna element in the linear array antenna.

[0032] In a specific embodiment of this utility model, a first via wall 7 is provided between two adjacent coupling power dividers 4 to ensure isolation between the antenna channels.

[0033] In a specific embodiment of this utility model, the 32 coupling power splitting units 4 and the first combining power splitter 2 are located on different layers of the PCB board 3, and the fourth end of the first directional coupler 41 of each coupling power splitting unit 4 is connected to the first combining power splitter 2 through a through-hole 412.

[0034] Because the introduction of the through-hole 412 causes impedance mismatch in the stripline, the first equal-amplitude in-phase power divider 42 is designed with two impedance transformation sections 421 to ensure port impedance. The two impedance transformation sections 421 are connected to a coaxial structure, each of which includes a signal hole 47 and ground holes 48 disposed around the signal hole 47.

[0035] In a specific embodiment of this utility model, the first coupling common port 6 and the first power supply port 45 can be selected as through-board connectors, so that the signal of the circuit can achieve internal circulation and eliminate the influence of structural components and other common ground components on the circuit performance.

[0036] This invention integrates the internal calibration circuit into the antenna, allowing for simple signal sampling at each feed port of the antenna using only a single circuit board. Analyzing the sampled signals enables calibration of the active phased array antenna. Furthermore, the use of striplines in the circuit design and directional couplers facilitates the formation of a relatively enclosed metal cavity, significantly isolating the influence of external interference signals and making the sampled or calibration signals more stable and reliable.

[0037] Example 2

[0038] Taking the antenna feeding and internal calibration circuit provided by this utility model, which includes 32 coupling power dividers 4, as an example, Figures 1 to 5 As shown, for the dual-polarized antenna feeding and internal calibration circuit, the circuit includes 32 coupling power dividers 4, a first combiner power divider 2 and a second combiner power divider 1, a first coupling common port 6 and a second coupling common port 5, and a PCB board 3. All 32 coupling power dividers 4, the first combiner power divider 2 and the second combiner power divider 1, the first coupling common port 6 and the second coupling common port 5 are integrated on the PCB board 3. Figure 5 As shown, each coupling power divider unit 4 includes a first directional coupler 41 and a second directional coupler 43, a first equal-amplitude in-phase power divider 42 and a second equal-amplitude in-phase power divider 44, a first feed port 45, and a second feed port 46. The first end of the first directional coupler 41 is connected to the first feed port 45, the second end of the first directional coupler 41 is connected to the first equal-amplitude in-phase power divider 42, and the third end of the first directional coupler 41 is connected to the load resistor. The first end of the second directional coupler 43 is connected to the second feed port 46, the second end of the second directional coupler 43 is connected to the second equal-amplitude in-phase power divider 44, and the third end of the second directional coupler 43 is connected to the load resistor. Figure 3 As shown, the fourth end of the first directional coupler 41 of each coupling power splitting unit 4 is connected to the first coupling common port 6 through the first combining power splitter 2; the fourth end of the second directional coupler 43 of each coupling power splitting unit 4 is connected to the second coupling common port 5 through the second combining power splitter 1. The first combining power splitter 2 and the second combining power splitter 1 are both matched to the number of coupling power splitting units 4. For 32 coupling power splitting units 4, both the first combining power splitter 2 and the second combining power splitter 1 have 32 channels. Figure 2 As shown.

[0039] In a specific embodiment of this utility model, the 32 coupling power splitting units 4 are located on different layers of the PCB board 3 with the first combining power splitter 2 and the second combining power splitter 1. The fourth end of the first directional coupler 41 of each coupling power splitting unit 4 is connected to the first combining power splitter 2 through a through-hole 412, and the fourth end of the second directional coupler 43 of each coupling power splitting unit 4 is connected to the second combining power splitter 1 through a through-hole 412.

[0040] Because the introduction of the through-hole 412 causes impedance mismatch in the stripline, both the first equal-amplitude in-phase power divider 42 and the second equal-amplitude in-phase power divider 44 employ two impedance transformation sections 421 to ensure port impedance. The two impedance transformation sections 421 are connected to a coaxial-like structure, each including a signal via 47 and ground vias 48 surrounding the signal via 47. The first feed port 45 and the second feed port 46 also employ a coaxial-like structure.

[0041] In a specific embodiment of this utility model, the first coupling common port 6 and the second coupling common port 5, the first power supply port 45 and the second power supply port 46 can be selected as through-board connectors, so that the signal of the circuit can achieve internal circulation and eliminate the influence of structural components and other common ground components on the circuit performance.

[0042] In a specific embodiment of this utility model, a second via wall 49 is provided between the first directional coupler 41 and the second directional coupler 43 of each coupling power distribution unit 4, and the isolation between the first directional coupler 41 and the second directional coupler 43 is achieved through the second via wall 49.

[0043] In a specific embodiment of this utility model, the first directional coupler 41 and the second directional coupler 43 of each coupling power division unit 4 are arranged in a rotationally symmetrical manner. By designing the two polarized power supply links in a rotationally symmetrical manner, the amplitude and phase consistency of the sampled signals are guaranteed in the design of the coupling signals of each port.

[0044] The above description only discloses specific embodiments of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or modifications that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. An antenna feeding and internal calibration circuit, characterized in that, The circuit adopts a stripline design and includes multiple coupling power splitting units, a first combining power splitter, a first coupling common port and a PCB board. The multiple coupling power splitting units, the first combining power splitter and the first coupling common port are integrated on the PCB board. Each of the coupling power dividers includes a first directional coupler, a first equal-amplitude and in-phase power divider, and a first feed port; the first end of the first directional coupler is connected to the first feed port, the second end of the first directional coupler is connected to the first equal-amplitude and in-phase power divider, and the third end of the first directional coupler is connected to the load resistor; the fourth end of the first directional coupler of each of the coupling power dividers is connected to the first coupling common port through a first combining power divider.

2. The antenna feeding and internal calibration circuit according to claim 1, characterized in that, A first through-hole wall is provided between two adjacent coupling power distribution units.

3. The antenna feeding and internal calibration circuit according to claim 1, characterized in that, The multiple coupling power splitting units and the first combining power splitter are located on different layers of the PCB board.

4. The antenna feeding and internal calibration circuit according to claim 1, characterized in that, The first equal-amplitude, in-phase power divider adopts a design with two impedance transformation sections, and the two impedance transformation sections are connected to a coaxial structure.

5. The antenna feeding and internal calibration circuit according to claim 4, characterized in that, Each of the aforementioned coaxial structures includes a signal aperture and a ground aperture disposed around the signal aperture.

6. The antenna feeding and internal calibration circuit according to any one of claims 1 to 5, characterized in that, The circuit further includes a second combiner power divider and a second coupling common port disposed on the PCB board; each coupling power divider unit further includes a second directional coupler, a second equal-amplitude and in-phase power divider and a second power supply port; the first end of the second directional coupler is connected to the second power supply port, the second end of the second directional coupler is connected to the second equal-amplitude and in-phase power divider, and the third end of the second directional coupler is connected to the load resistor; the fourth end of the second directional coupler of each coupling power divider unit is connected to the second coupling common port through the second combiner power divider.

7. The antenna feeding and internal calibration circuit according to claim 6, characterized in that, A second via wall is provided between the first directional coupler and the second directional coupler of each of the coupling power distribution units.

8. The antenna feeding and internal calibration circuit according to claim 7, characterized in that, The first directional coupler and the second directional coupler of each of the coupling power distribution units are arranged in a rotationally symmetrical manner.

9. An active phased array antenna, characterized in that, The active phased array antenna includes the antenna feeding and internal calibration circuit as described in any one of claims 1 to 8.

10. A radar, characterized in that, The radar includes the active phased array antenna as described in claim 9.

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