S-band phased array antenna

Abstract

The invention discloses an S-band phased array antenna. Comprising an array antenna, an adjusting platform, an antenna connecting wire harness, a middle wire harness, a power amplifier connecting wire harness and a power amplifier assembly, the array antenna is arranged on the adjusting platform, the adjusting platform can adjust the inclination angle of the array antenna, and the antenna connecting wire harness and the power amplifier connecting wire harness are electrically connected between the array antenna and the power amplifier assembly; the array antenna comprises a plurality of intermediate plates, a plurality of antenna units are arranged on the intermediate plates, and the antenna units are symmetrically distributed in the longitudinal direction and the transverse direction. In the application, the array antenna is arranged on the adjusting platform, the inclination angle of the array antenna can be flexibly adjusted through the adjusting platform, so that flexible application of the array antenna is facilitated, and the array antenna is electrically connected with the power amplifier assembly through the antenna connecting wire harness, the middle wire harness and the power amplifier connecting wire harness, so that the array antenna and the power amplifier assembly can be separately used; and the possibility that the power amplifier assembly is damaged is greatly reduced, so that the use cost of the phased-array antenna is reduced.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to an S-band phased array antenna. Background Art

[0002] Phased array antennas are favored and widely used in various communication fields due to their fast beam scanning capability, fast beam shape change capability, spatial orientation and spatial high-power synthesis capability, low sidelobe and high reliability. Phased array antennas are composed of four major modules, namely antenna array module, transmitting module, array module, power division network module, beam controller and power supply unit module. Usually, the antenna array module is integrated with the transmitting module, array module and power division network module. When the antenna array module is damaged by foreign objects, it can still be used. Once the structures such as the transmitting module, array module and power division network module are damaged by foreign objects, the phased array antenna is difficult to continue to use. Therefore, when the antenna array module is integrated with the transmitting module, array module and power division network module, it is easy to affect the use of the phased array antenna due to the damage of the transmitting module, array module and power division network module, which increases the cost of using the phased array antenna. Summary of the invention

[0003] The main technical problem solved by the present application is to provide an S-band phased array antenna to solve the problem of increased use cost of the phased array antenna when the antenna array module is integrated with the transmitting module, the array module and the power division network module.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is to provide an S-band phased array antenna, including an array antenna, an adjustment platform, an antenna connection harness, an intermediate harness, a power amplifier connection harness and a power amplifier assembly; the array antenna is arranged on the adjustment platform, and the adjustment platform can adjust the inclination angle of the array antenna, the two ends of the intermediate harness are respectively connected to one end of the antenna connection harness and the power amplifier connection harness, the other end of the antenna connection harness is connected to the array antenna, and the other end of the power amplifier connection harness is connected to the power amplifier assembly; the antenna connection harness and the antenna connection harness are respectively used to connect the connection ports of the array antenna and the power amplifier assembly to the intermediate harness; the intermediate harness is used to increase the distance between the array antenna and the power amplifier assembly, and the array antenna includes multiple intermediate plates, and multiple antenna units are arranged on the intermediate plates, and the antenna units are symmetrically distributed in the longitudinal and transverse directions.

[0005] The beneficial effects of the present application are as follows: in the present application, the array antenna is arranged on an adjustment platform, and the inclination angle of the array antenna can be flexibly adjusted through the adjustment platform, thereby facilitating the flexible application of the array antenna, and the power amplifier component is electrically connected through the antenna connecting harness, the intermediate harness and the power amplifier connecting harness, so that the array antenna can be separated from the power amplifier component for use, which can set the power amplifier component separately in a safe position to prevent the power amplifier component from being damaged by foreign objects along with the array antenna, which greatly reduces the possibility of damage to the power amplifier component, thereby reducing the cost of using the phased array antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a structural schematic diagram according to an embodiment of the present application;

[0007] Figure 2 is a schematic structural diagram of an outer cover according to an embodiment of the present application;

[0008] Figure 3 is a schematic diagram of incident waves and outgoing waves of an outer cover according to an embodiment of the present application;

[0009] Figure 4 is a structural schematic diagram according to an embodiment of the present application;

[0010] Figure 5 is a schematic diagram of a rear view structure according to an embodiment of the present application;

[0011] Figure 6 is a schematic diagram of a side view structure according to an embodiment of the present application;

[0012] Figure 7 is a schematic diagram of the structure inside the outer cover according to an embodiment of the present application;

[0013] Figure 8 is a schematic diagram of a top view of the structure inside the outer cover according to an embodiment of the present application;

[0014] Fig. 9 is a schematic structural diagram of a convergent housing according to an embodiment of the present application;

[0015] Fig.10 is a structural schematic diagram of an antenna unit according to an embodiment of the present application;

[0016] Fig.11 It is a simulation result of standing wave at a typical port of an antenna in an array according to an embodiment of the present application;

[0017] Fig.12 is a simulation result of the array normal horizontal plane pattern according to an embodiment of the present application;

[0018] Fig.13 It is a simulation result of the normal pitch plane pattern of the array according to an embodiment of the present application;

[0019] Fig.14 This is a simulation result of the elevation pattern when the beam is scanned to theta=20° and phi=0° according to an embodiment of the present application;

[0020] Fig.15 This is a simulation result of the elevation pattern when the beam is scanned to theta=10° and phi=0° according to an embodiment of the present application;

[0021] Fig.16 This is a simulation result of the elevation pattern when the beam is scanned to theta = -10°, phi = 0° according to an embodiment of the present application;

[0022] Fig.17 This is a simulation result of the elevation pattern when the beam is scanned to theta=-20° and phi=0° according to an embodiment of the present application;

[0023] Fig.18 This is a simulation result of the elevation pattern when the beam is scanned to theta = -25°, phi = 35° according to an embodiment of the present application;

[0024] Fig.19 This is a simulation result of the elevation pattern when the beam is scanned to theta=25°, phi=35° according to an embodiment of the present application;

[0025] Fig. 20 is a schematic diagram of the structure of an adjustment platform according to an embodiment of the present application;

[0026] Fig.21 It is a structural schematic diagram of an overall connection block diagram of an antenna according to an embodiment of the present application;

[0027] Fig. 22 is a structural schematic diagram of cable connection according to an embodiment of the present application;

[0028] Fig.23 This is a schematic diagram of the structure of a U-shaped square tube according to an embodiment of the present application;

[0029] Fig.24 It is a cloud diagram of the external temperature distribution of the cable harness according to an embodiment of the present application;

[0030] Fig.25 It is a temperature distribution cloud diagram inside a cable harness according to an embodiment of the present application;

[0031] Fig.26 is a flow chart of transmitting a signal according to an embodiment of the present application;

[0032] Fig. 27 is a schematic diagram of a simulation model of a power amplifier component according to an embodiment of the present application;

[0033] Fig.28is a schematic diagram of a circuit amplifier heat dissipation simulation model according to an embodiment of the present application;

[0034] Fig.29 is a surface temperature cloud diagram of a circuit amplifier component according to an embodiment of the present application;

[0035] Fig.30 It is a temperature cloud diagram of the circuit amplifier component according to an embodiment of the present application;

[0036] Fig.31 This is a temperature cloud diagram of an internal circuit amplifier component according to an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of this application.

[0038] It should be noted that when an element is referred to as being "fixed on" or "set on" another component, it can be directly on the other component or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0039] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In addition, 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 the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0041] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which this application can be implemented, so they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.

[0042] Figure 1-Figure 10 An embodiment of the S-band phased array antenna of the present application is shown, including an array antenna 10, an adjustment platform 20, an antenna connection harness 30, an intermediate harness 40, a power amplifier connection harness 70 and a power amplifier assembly 50; the array antenna 10 is arranged on the adjustment platform 20, and the adjustment platform 20 can adjust the inclination angle of the array antenna 10, the two ends of the intermediate harness 40 are respectively connected to one end of the antenna connection harness and the power amplifier connection harness, the other end of the antenna connection harness is connected to the array antenna, and the other end of the power amplifier connection harness is connected to the power amplifier assembly; the antenna connection harness and the antenna connection harness are respectively used to connect the connection ports of the array antenna and the power amplifier assembly to the intermediate harness 40; the intermediate harness 40 is used to increase the distance between the array antenna and the power amplifier assembly, and the array antenna 10 includes a plurality of intermediate plates 2, and a plurality of antenna units 3 are arranged on the intermediate plates 2, and the antenna units 3 are symmetrically distributed in the longitudinal and transverse directions.

[0043] In the present application, the array antenna 10 is set on the adjustment platform 20, and the inclination angle of the array antenna 10 can be flexibly adjusted through the adjustment platform 20, so as to facilitate the flexible application of the array antenna 10, and the power amplifier component 50 is electrically connected through the antenna connection harness 30, the intermediate harness 40 and the power amplifier connection harness 70, so that the array antenna 10 can be separated from the power amplifier component 50 for use, so that the power amplifier component 50 can be set separately in a safe position, avoiding the power amplifier component 50 from being damaged by foreign objects together with the array antenna 10, which greatly reduces the possibility of damage to the power amplifier component 50, thereby reducing the cost of using the phased array antenna.

[0044] In some embodiments, Figure 2-Figure 9 As shown, the array antenna 10 includes an outer cover 1, an intermediate plate 2, antenna units 3, a converging shell 4 and a hub 5. The outer cover 1 and the converging shell 4 cover both sides of the intermediate plate 2. The antenna unit 3 is arranged on the intermediate plate 2 and extends toward the outer cover 1. The antenna units 3 are unevenly sparsely arrayed on the intermediate plate 2. The hub 5 is arranged on the converging shell 4. The connecting wires of the antenna units 3 converge on the hub 5. The hub 5 is used to connect the power amplifier assembly 50 through the antenna connecting harness 30, the intermediate harness 40 and the power amplifier connecting harness 70.

[0045] The array antenna 10 is a passive array and is placed separately. The active devices including phase shift and amplitude control network are integrated in the power amplifier component 50 and placed away from the radiating antenna. The middle is connected by the antenna connection harness 30, the intermediate harness 40 and the power amplifier connection harness 70. One power amplifier component 50 is connected to a group of antenna connection harnesses 30, the intermediate harness 40 and the power amplifier connection harness 70, so as to connect all the antenna units 3 on an intermediate board 2. The radiating antenna frame is simple and the radiating antenna has high reliability. The antenna units 3 are unevenly sparsely arrayed on the intermediate board 2, so as to reduce the number of antenna elements and reduce costs. At the same time, it prevents the occurrence of grating lobes and can well control the side lobe level in the specified airspace.

[0046] In some embodiments, the outer cover 1 is frame-shaped and has a three-layer structure, such as Figure 2 As shown, there are an outer layer 11, a middle layer 12 and an inner layer 13 in sequence, and the inner layer 13 is adjacent to the middle plate 2. The inner layer 13 and the outer layer 11 are made of epoxy resin quartz cloth, and the middle layer 12 is made of hard foam.

[0047] The inner layer 13 and the outer layer 11 include multiple layers of epoxy resin quartz cloth, which are formed by high-temperature pressing of multiple layers of quartz cloth and hydroamine. While having high strength, the epoxy resin quartz cloth has a smaller loss angle, which can reduce the loss of antenna signals. The thickness of each layer of quartz cloth in the epoxy resin quartz cloth is 0.3mm-0.8mm, and the thickness of the inner layer 13 and the outer layer 11 can be 0.6mm-3mm, such as 0.6mm, 0.8mm, 1mm, 1.5mm, 2mm and 3mm. The relative dielectric constant of quartz cloth is about 3.8, and the loss tangent value is low. The relative dielectric constant of hydroamine is about 3.3, and the loss tangent value is about 4 / 10,000.

[0048] In some embodiments, the thickness of the inner layer 13 is less than the thickness of the outer layer 11. The thicker outer layer 11 can ensure that the outer layer 11 has a better protective effect, and the thinner inner layer 13 can reduce the loss of the antenna signal.

[0049] The middle layer 12 is a hard foam, and the thickness of the middle layer 12 is 1 mm-5 mm, such as 1 mm, 2 mm, 3 mm, 4 mm and 5 mm, etc. The relative dielectric constant of the middle layer 12 is 1.02-1.06, and the loss tangent value is about 1 / 10,000.

[0050] The normal wave transmittance of the outer cover 1 at 5.5GHz is 93.2%, and the comprehensive wave transmittance is 90.4%. The insertion loss caused by its wave transmittance is 0.43dB, and a 0.5dB insertion loss margin is left for the outer cover 1 in engineering.

[0051] The design of the outer cover is as follows: The goal of the outer cover design is mainly to determine the thickness of the three layers. The constraint condition is: under the premise of leaving a certain engineering margin, the average wave transmittance in a certain incident wave space is above 95% (η≥95%). The design needs to determine the number of layers of the inner and outer layers of hydroamide quartz cloth, and the thickness of the middle layer is 2mm.

[0052] The industry generally defines the transmittance of the outer cover as the ratio of the energy of the normal incident plane wave to the energy of the plane wave after passing through the outer cover. Normal incidence refers to only considering the incident direction perpendicular to the outer cover surface. However, the outer cover of this application needs to take into account the transmission conditions of all angles within the beam coverage range during design (named as comprehensive transmittance in this application), for the following reasons: 1. The frequency band is wide and the beam width of the antenna is wide. An inadequately designed outer cover may have a notch effect at low elevation angles of certain frequencies, resulting in relatively large spatial insertion loss; 2. It is necessary to consider the broadband coupling of the transmitting and receiving antennas in order to achieve the goal of not deteriorating the transmit and receive isolation. This requires full consideration of the slow wave effect that may appear on the surface of the outer cover at low elevation angles. Although its radiation capability is not strong, after superimposing with the reflected wave of the bottom plate, some airspace may be strengthened, thereby deteriorating the isolation.

[0053] In some embodiments, Figure 3 As shown in the figure, the incident wave airspace considered by the comprehensive wave transmittance is defined as the airspace formed by the maximum scanning angle beam coverage angle of the antenna around the antenna axis, that is, Ω1:θ∈(0°,35°), The calculation formula of comprehensive wave transmittance η1 is as follows:

[0054]

[0055] Where: S 21 is the transmission coefficient of the incident wave power through the outer cover, Ω is the airspace of the array coordinate system in the phased array antenna, Ω1 is the airspace of the geodetic coordinate system, θ is the incident angle of the plane wave, θ∈(0°,35°), is the projection vector of the target direction vector on the XOY plane and the angle between the X axis, The target direction is the source or sending direction of the signal.

[0056] S 21 The value range is between 0 and 1. When it is 1, it is fully transmitted and the cover has no loss. When it is 0, the electromagnetic waves are completely absorbed or reflected by the cover. According to the oblique incidence theory of plane electromagnetic waves in multilayer media in electromagnetic field theory, S 21 is a function of the incident angle θ. The larger the angle θ, the greater the S 21 The smaller it is, the greater the insertion loss of the outer cover. 21The determination of S can be done with the help of the simulation software AnsyS HFSS. In the simulation software, the periodic boundary conditions are set to simulate the infinite cover, load the plane wave, observe the transmission performance of the plane wave, change the incident angle θ of the plane wave, and the frequency f of the incident electromagnetic wave, and calculate S in all states. 21 Parameters are extracted and the comprehensive wave transmittance η1 is calculated.

[0057] Taking into account the strength and wave transmittance calculation results of the outer cover 1, the configuration of the outer cover 1 is as follows: the thickness of the inner layer 13 of the hydroamide quartz cloth is 0.6mm, the thickness of the middle layer 12 is 3mm, and the thickness of the outer hydroamide quartz cloth is 0.6mm; at this time, the normal wave transmittance of the 5.5GHz array is 93.2%, and the comprehensive wave transmittance is 90.4%. The insertion loss caused by its wave transmittance is 0.43dB. The outer cover 1 is 10mm away from the antenna at the shortest distance, with a thickness of 4.2mm. It is fixed by screws and the middle plate 2 on all sides, and has a corresponding waterproof design.

[0058] In some embodiments, Figure 7 and Figure 8 As shown, the middle plate 2 is formed by splicing a plurality of sub-plates 21, and the number of the sub-plates 21 is 4, 6 or 8, etc. When the number of the sub-plates 21 is set to 4, the 4 sub-plates 21 are arranged vertically and horizontally, and the sub-plates 21 are symmetrically arranged with respect to the longitudinal center line and the transverse center line, and the 4 sub-plates 21 are connected together by a cross.

[0059] The convergence housing 4 is provided corresponding to the middle board 2 or the sub-board 21. When the middle board 2 is an integrated structure, one convergence housing 4 is provided. When the middle board 2 is formed by splicing a plurality of sub-boards 21, the number of convergence housings 4 corresponds to the number of sub-boards 21, and each sub-board 21 corresponds to one convergence housing 4. The connection lines of the antenna unit 3 on the sub-board 21 converge to the hub 5 of the corresponding convergence housing 4.

[0060] like Fig. 9 As shown, the convergence shell 4 is in the shape of a trumpet, the trumpet mouth adjacent to the middle plate 2 has a larger diameter, and the trumpet mouth away from the middle plate 2 has a smaller diameter. A plurality of hubs 5 are provided, arranged at the trumpet mouth away from the middle plate 2. The trumpet shape of the convergence shell 4 can facilitate the integration of the connecting wires of the antenna unit 3 into the inner wall of the convergence shell 4, and reduce the space occupied by the connecting wires enclosed by the outer cover 1 and the convergence shell 4. This can also prevent the connecting wires from interfering with each other when they are laid. The connecting wires are guided and converged by the convergence shell 4, and the hub 5 seals the feeding connector on the inner side of the convergence shell 4, thereby improving the feeding reliability of the antenna unit 3 and facilitating the plug-in connection with the antenna connection harness 30.

[0061] A plurality of connection terminals are arranged on both side surfaces of the wiring hub 5 . The connection terminals adjacent to the middle plate 2 are connected to the connection wires of the antenna unit 3 , and the connection terminals away from the middle plate 2 are connected to the antenna connection harness 30 .

[0062] In some embodiments, Fig.10 As shown, the antenna unit 3 includes a fixing seat 31 and a radiating element 32. The radiating element 32 is fixed on the fixing seat 31. A bayonet adapted to the fixing seat 31 is provided on the middle plate 2, and the fixing seat 31 is fixed at the bayonet. The fixing seat 31 is in a stepped shape. The radiating element 32 includes a fixing portion 321, a main body 322 and a branch portion 323. The fixing portion 321 is in a square structure and is fixed on the fixing seat 31. The main body 322 is vertically arranged on the fixing portion 321. A plurality of branch portions 323 are provided, extending outward from the side of the main body 322, and the branch portions 323 are evenly distributed on both sides of the main body 322. There are 10 branch portions 323, and the 10 branch portions 323 are located on both sides of the main body 322, and are symmetrically arranged with respect to the vertical center line of the main body 322. The branch portions 323 are, from top to bottom, a first branch portion 323 , a second branch portion 323 , a third branch portion 323 , a fourth branch portion 323 and a fifth branch portion 323 .

[0063] A dielectric plate 324 is provided on the lower side of the main body 322 on the side opposite to the fixing portion 321. The upper end of the dielectric plate 324 is located between the first branch portion 323 and the second branch portion 323. A microstrip line is provided on the dielectric plate 324 for feeding the antenna unit 3. A grounding hole is provided on the dielectric plate 324 for grounding.

[0064] The main body 322 on the upper side of the fixing part 321 has a protruding part 326, the upper end of which is located between the first branch part 323 and the second branch part 323. The protruding part 326 is used to enhance the structural strength of the lower side of the fixing part 321 and adjust the performance of the antenna unit 3.

[0065] A choke slot 325 is provided at the main body 322 on the upper side of the fixing portion 321, and the upper end of the choke slot 325 extends to the upper side of the second branch portion 323. The lower end of the choke slot 325 penetrates the fixing portion 321 and extends in a direction away from the dielectric plate 324. The choke slot 325 is used to ensure that only the first branch portion 323 is fed with power.

[0066] In the sparsely arranged phased array of the S band, the number of antenna units 3 is 144, and the unit spacing is 0.75 wavelengths of the center frequency of 3.3GHz. The position of each unit is optimized by genetic algorithm and sparsely distributed in an area that can accommodate 16×16 units according to a certain rule. The size of the entire array (including the ground size) is 1072mm×1072mm. The entire array is strictly symmetrical along the horizontal and elevation directions and about the center of the array.

[0067] The standing wave simulation results of the typical antenna port are as follows: Fig.11 As shown, the standing waves of the unit ports at the edge and center of the array are all below 2 in the range of 3.1 GHz to 3.5 GHz.

[0068] The center frequency is 3.3 GHz, and the simulation results of the normal beam are as follows: Fig.12 and Fig.13 As shown, at the center frequency of 3.3 GHz, the normal gain is 3.5 dBi, the elevation beamwidth is 3.8°, and the horizontal beamwidth is 4.2°.

[0069] The beam scans to theta = 20°, phi = 0°, which is equivalent to the simulation result of the main lobe sweeping 20°. Fig.14 As shown, the gain is 30.4dBi and the beamwidth is 4.1°.

[0070] The beam scans to theta = 10°, phi = 0°, which is equivalent to the simulation result of the main lobe sweeping 10°. Fig.15 As shown, the gain is 31.3dBi and the beamwidth is 3.9°.

[0071] The beam scans to theta = -10°, phi = 0°, which is equivalent to the main lobe scanning down 10°. The simulation results are as follows Fig.16 As shown, the gain is 31.3dBi and the beamwidth is 3.9°.

[0072] The beam scans to theta = -20°, phi = 0°, which is equivalent to the main lobe scanning 20° down. The simulation results are as follows Fig.17 As shown, the gain is 30.4dBi and the beamwidth is 4.1°.

[0073] The beam scans to theta = -25°, phi = 35°, which is equivalent to the main lobe sweeping 25° down and 35° right. The simulation results are as follows: Fig.18 As shown, the gain is 29.6dBi and the beamwidth is 4.4°.

[0074] The beam scans to theta = 25°, phi = 35°, which is equivalent to a main lobe sweep of 25° up and 35° right. The simulation results are as follows: Fig.19 As shown, the gain is 29dBi and the beamwidth is 4.2°.

[0075] The above scanning angle data are summarized in Table 1. From Table 1, it can be seen that the maximum gain drop in the scanning area relative to the normal beam is -1.9dB, and no grating lobe appears in the entire airspace. After weighting, the average sidelobe level in the entire scanning area can meet the requirement of greater than -20dBc, and the maximum sidelobe is less than -9dB.

[0076] Table 1 Statistics of various scanning angles of sparse planar phased array at 3.3 GHz

[0077]

[0078] The statistical results of the 3dB beam width at each scanning angle are shown in Table 2. In the normal direction, the beam widths of the elevation plane and the horizontal plane are 3.8° and 4.2° respectively. During the scanning process, the beam width of the elevation plane is between 3.6° and 4.4°, and the beam width of the horizontal plane is between 4.2° and 5°. The beam widths of the two planes meet the requirement of being between 3° and 6°.

[0079] Table 2 Statistics of 3dB beamwidth at various scanning angles at 3.3GHz

[0080]

[0081] The main lobe of the phased array antenna needs to cover the airspace of ±35° in azimuth and 0° to 50° in elevation in the geodetic coordinate system. The 3dB beam width of the antenna main lobe in the scanning state needs to be controlled within 3 to 6 degrees, and the beam pointing conversion speed should not exceed 100us so that the beam switching can be completed within one repetition cycle; the pointing angle accuracy shall not exceed 1.5 degrees, so that the approximate EIRP reduction of the beam pointing error can be within 1dB; the beam stepping needs to be controlled within the 3dB beam width so as to have coverage capabilities in every direction in the airspace; the EIRP value in the normal direction of the phased array face needs to be greater than 66dBW, and there is no clear requirement for the EIRP value in other directions, but it should meet the normal working requirements of the system, that is, meet the gain reduction caused by the reduction in the effective aperture cross-sectional area of ​​the face in the beam scanning state, and on this basis it should not be too large.

[0082] When all beams of the phased array are scanned, the average sidelobe equivalent radiated power in the airspace of ±20° in azimuth and 0° to 30° in elevation in the geodetic coordinate system should be no less than 46dBW (i.e. greater than -20dBC). The radiated power in this airspace needs to be about 5dB lower than the radiated power of the decoy body. It should not be too low, otherwise the difference from the decoy body will be too obvious, which is not conducive to the inspection of anti-radiation; it should not be too high, otherwise the radiated power of the decoy body needs to be increased, which will increase the system cost. The average sidelobe equivalent radiated power is defined as the average of the absolute values ​​of all sidelobe peak powers in the airspace; the radiated power at this point of the sidelobe is a maximum point in the surrounding airspace, and should not contain a maximum point lower than -30dBc.

[0083] The polarization mode of the S-band phased array antenna is horizontal polarization, so all units should meet this polarization requirement. When installed independently, the lower edge of the antenna array needs to be about 1.5m from the ground. The bracket and antenna frame are covered with absorbing materials and radiate upward at a certain elevation angle to reduce the impact of ground plane multipath effects on radiation. The azimuth angle (0 to 360 degrees) and pitch angle (0 to 65 degrees) of the antenna array normal can be adjusted manually. After adjustment, the accurate pointing angle needs to be tested so that the working state after coordinate transformation can meet the index design requirements.

[0084] When laying the antenna, it needs to be installed on the azimuth and pitch adjustment platform 20. When the adjustment platform 20 is laid on the ground, it is necessary to first pour a concrete foundation and pre-embed 6 M24 screws. After the concrete foundation solidifies, the mounting surface of the adjustment platform 20 is inserted into the screws and tightened with nuts.

[0085] In some embodiments, Fig. 20 As shown, the adjustment platform 20 includes a support column 201, a base 202, a first direction rotation motor 203 and a second direction rotation motor 204; the first direction rotation motor 203 is arranged on the support column 201, driving the base 202 to rotate along the first direction, so as to change the inclination angle of the array antenna 10; the second direction rotation motor is arranged on the base 202, and the second direction rotation motor is connected to the array antenna 10, driving the array antenna 10 to rotate along the second direction, so as to change the rotation angle of the array antenna 10.

[0086] When the antenna array is in use, the pitch (first direction) and azimuth (second direction) angles need to be adjusted to achieve beam coverage. Therefore, the first direction rotating motor 203 and the second direction rotating motor 204 are implemented using a commutation harmonic reducer. Commutation harmonic reducers are installed at the azimuth and pitch joints, respectively. The pointing accuracy of the reducer is ≤0.1°, and the output torque is relatively high, which meets the rotational inertia of the antenna array. The interior is filled with aerospace grease to meet the low operating temperature of -45°C. The support column 201 is the foundation of the entire adjustment system, supporting the mechanical load caused by the weight of the antenna and the environment, and must have sufficient rigidity. In order to ensure the structure of the servo adjustment platform 20 and reduce the overall weight, the main parts of the adjustment platform 20 are made of aluminum alloy series materials. At the same time, in order to meet the requirements of outdoor salt spray, corrosion, humidity and heat protection, after the adjustment platform 20 is assembled, all the outer surfaces of the adjustment platform 20 are spray-painted. Fig. 20 When the array is erected and used, the windward side of the array is impacted by the environmental wind, which may cause structural damage to the array. Reliability design is achieved by adding reinforcement ribs to the back of the antenna array.

[0087] The array antenna 10 and the power amplifier component 50 are connected by a cable to form a phased array antenna. When attacked, the relatively expensive power amplifier component 50 can be protected with a high probability. The cable length is 15m and can be extended to 30m. When selecting the connecting cable, the cable insertion loss, as well as the power consumption and heat dissipation caused by the insertion loss should be fully considered. At the same time, the transmission performance of the cable at different temperatures needs to be analyzed. In addition, when designing the system, it is necessary to focus on evaluating the composition of the phased array antenna and then clarify the cable connection form.

[0088] In some embodiments, Figure 1 and Fig.21 As shown, the antenna connection harness 30 and the amplifier connection harness 70 are both soft cable assemblies. The intermediate harness 40 is a hard cable assembly. The overall connection block diagram of the S-band phased array antenna is shown in FIG. Fig.21 As shown, the installation distance between the radiation vehicle and the array antenna 10 is 20 meters, and can be extended to 30 meters.

[0089] The power amplifier assembly 50 and the array antenna 10 are connected through the antenna connection harness 30, the intermediate harness 40 and the power amplifier connection harness 70. Each group of cables in the hard cable assembly is composed of a number of low-loss hard cables. Therefore, the hard cable assembly needs to consider heat dissipation measures. The length is 20 meters, and its cross-sectional area needs to be determined by comprehensive thermal design. Heat dissipation fin measures need to be designed between each hard cable assembly. The relative position and relative state of each hard cable in the hard cable assembly are fixed and will not change during installation and use. If it needs to be extended to 30 meters, two sections of hard cable assemblies need to be connected through a soft cable assembly. The connectors on both sides of the hard cable assembly need to be on the same plane and connected to the soft cable assembly by plugging.

[0090] The feeding port of the array antenna 10 and the output port of the power amplifier assembly 50 are designed to be symmetrical as much as possible, so that even if the array surface or the power amplifier size is large, the flexible cable assembly can be plugged in by area to meet the interchangeability. The flexible cable assembly also needs to be plugged in when docking and locked by a flange. The deformation of the flexible cable assembly should be controlled as much as possible when in use.

[0091] The electrical connection from the power amplifier assembly 50 to the array antenna 10 adopts the method of soft cable assembly + hard cable assembly and soft cable assembly. This set of cables needs to be numbered before use, the plug-in relationship needs to correspond one to one, the delay of each path needs to be accurately measured, and the results need to be integrated into the wave control software before use.

[0092] The hard cable assembly can use S-band corrugated tubes, with a single outer conductor diameter of 25mm. Its insertion loss at a length of 20 meters in the 3.1-3.5GHz frequency band is 2.1dB, and its power resistance is higher than 1000W continuous wave. Each cable in the soft cable assembly can also use the same specification corrugated tube, and 2 meters are reserved for the array antenna 10 and the power amplifier assembly 50. The intermediate connectors all use plug-in connectors, and the link insertion loss budget is shown in Table 1.1; when extended to 30 meters, 1 meter of length is required between the two hard cable assemblies, and the soft cable assembly is connected to the array antenna 10 or the power amplifier assembly 50.

[0093] When the array antenna 10 is actually used, it is necessary to transmit signals with the power amplifier component 50 25 meters away. Since the transmission power of a single antenna unit 3 is relatively large, in order to reduce the transmission insertion loss, the hard cable component adopts a low insertion loss corrugated tube cable for transmission. Considering that the layout distance between the hard cable component and the power amplifier component 50 is relatively long, a segmented plug-in interconnection is adopted to divide the cable into 3 sections, namely a 25-meter-long fixed corrugated tube hard cable harness, a 1-meter-long antenna input model 3449 soft cable harness and a transmitting power amplifier output model 3449 soft cable harness. Since there are many antenna units 3, the 144 antenna input cables are connected through a convergent external The shell 4 guides the flow into 4 paths and connects them to the 25-meter fixed cable respectively. The connector model is BMA-KF3449. The connector is small in size and can be installed by plugging in. The connector interface is designed with mounting flanges and guides for plugging in and positioning each section of the cable. The connection of the power amplifier component 50 is consistent with the antenna input terminal. The internal transmission power of the fixed corrugated tube harness is relatively large. Considering the influence of temperature on the cable phase, the heat dissipation design is such that the internal part of the fixed corrugated tube itself is in contact with the harness shell over a large area to reduce thermal resistance. The fixed corrugated tube harness shell increases the heat dissipation area by adding heat dissipation fins to improve the convection efficiency with the external environment. The layout diagram is as follows: Figure 1 shown.

[0094] The 144 antenna units 3 in the antenna array need to be connected to the BMA-KF3449 connector and the transmission cable for interconnection. Considering that the array layout of the antenna unit 3 is relatively divergent, each channel is first numbered, and then the external connector of the antenna unit 3 is divided into 4 groups and integrated on the connector mounting flange through the convergent shell 4. During actual installation, when multi-channel connectors are connected together, the plug-in torque is large and the positioning is inaccurate. Therefore, the connection method is optimized. Through reasonable estimation, when the 8-channel connectors are plugged together, the plug-in torque is reasonable, the installation surface is small, and positioning is convenient. The 4 groups of connectors after convergence are arranged into two groups of 5×8 and 4×8 respectively, forming a 144-channel arrangement. The input-end cable is divided into 18 cables with corresponding numbers for plugging and unplugging. The input-end cable adopts a flexible cable to facilitate the corresponding cable adjustment when the antenna angle is adjusted. The input-end cable connector mounting surface is designed with positioning pins and mounting holes to facilitate positioning and fixation during cable laying.

[0095] Because the corrugated tube cable is laid for a long time, obstacles may be encountered during the overall laying. The 3m square tube flange connection can be separated, the angle can be fine-tuned, and the obstacles can be avoided to continue laying. The split-end U-shaped square tube 401 design is more flexible during on-site laying, such as Fig.23 The U-shaped square tube 401 includes a cover plate 402 , and there is a receiving space between the cover plate 402 and the U-shaped square tube 401 . The corrugated tubes are stacked in sequence in the U-shaped square tube 401 .

[0096] In order to facilitate plugging and unplugging, the layout design of the bellows butt joint end and the input cable interface end is consistent through numbering. According to the diameter of the bellows cable, they are arranged into 8×18, a total of 144 channels. During actual layout, the U-shaped square tube 401 is first lowered and laid on site. The length of each section of the U-shaped square tube 401 is 3m, which is extended to 25m through the installation flange. A guide rail is designed at the bellows interface end, and the 8-channel bellows harness slides into the U-shaped square tube 401 through the guide rail. The arrangement is repeated until all 144 channels slide into the U-shaped square tube 401, and then the cover plate 402 is fixed and sealed with the U-shaped square tube 401 by screws. An insulating limit block 403 is designed at the bellows interface to prevent internal cable dislocation interference. Due to the large diameter of the bellows cable, it cannot be directly installed. The BMA plug-in connector needs to be transferred through the N / BMA-KFJ adapter end 404. After the transfer, it is plugged and connected with the antenna connection harness 30 or the power amplifier connection harness 70. Fig. 22 shown.

[0097] When cables are set at both ends of the corrugated tube to transmit signals, the cable load power consumption is large, resulting in high cable heat loss, excessive cable temperature and influence on the cable phase, so the cable is thermally designed and analyzed. The 144 transmission cables are fixed in the wiring harness structure cavity according to the guide. The wiring harness cavity is made of aluminum, which has a high thermal conductivity, good strength and economy. The surface spraying treatment increases the emissivity ε. The surface emissivity ε after spraying can reach more than 0.8. The cable is fully in contact with the wiring harness cavity, which increases the heat exchange area, reduces the thermal resistance on the transmission path, and improves the thermal conductivity efficiency.

[0098] The input power (thermal simulation based on average power) and output power of a single cable are used to calculate the heat loss on each section of the cable; the cable temperature changes in a unit time at an ambient temperature of 25°C are simulated. According to the analysis of the cable installation environment, the main heat dissipation pathways are heat conduction, wall radiation, and weak convection between the structure and the environment. The heat dissipation area is increased by designing heat dissipation fins, and the cable is installed in close contact with the radiator of the harness housing over a large area to reduce the thermal resistance on the conduction path. The radiation heat dissipation wall and radiation emissivity are set, the thermal conductivity of the material is set, the contact thermal resistance is set between the heat source and the carrier, and the solution domain is set to simulate the ambient temperature and convection coefficient. The temperature cloud map distribution after cable simulation is as follows: Fig.24 and Fig.25 shown.

[0099] Table 3 Temperature results of 1-125℃ treatment

[0100] Position No. Single heat consumption (W) Quantity(pcs) Total power consumption (W) Temperature ℃ Temperature rise ℃ 0-2 m 0.93 100 93 48.1 23.1 2-4 meters 0.88 100 88 47.5 22.5 4-6 meters 0.83 100 83 46.3 21.3 6-8 meters 0.78 100 78 45 20 8-10 meters 0.73 100 73 43.4 18.4 10-12 meters 0.68 100 68 41.9 16.9 12-14 meters 0.64 100 64 39.6 14.6 14-16 meters 0.60 100 60 36.1 11.1 16-18 meters 0.57 100 57 35.2 10.2 18-20 meters 0.53 100 53 34.5 9.5

[0101] As shown in Table 3, a large amount of heat from the cable is exchanged with the external air through the structure, and the temperature difference between the cable conductor and the casing is small, which means that the thermal resistance of the conduction path is small, the temperature rise at each end is stable, the temperature inside the structure is uniform, the structure is stable and reliable, and the cable phase is less affected.

[0102] In some embodiments, Fig.26 As shown, the power amplifier component 50 of the S-band phased array antenna includes an amplifying module 501, multiple power dividing modules 502 and multiple transmitting modules 503. The amplifying module 501 is electrically connected to the array antenna 10 through the antenna connecting harness 30, the intermediate harness 40 and the power amplifier connecting harness 70, and is used to amplify the signal of the array antenna 10; the power dividing module 502 is electrically connected to the amplifying module 501 and the transmitting module 503, and is used to evenly distribute the amplified signal of the array antenna 10 to the transmitting module 503.

[0103] The output power of each transmitting module 503 in the S band is 23.2dBW, and the gain of the transmitting module 503 is at least 55dB. The required input power after the pre-stage split is -1dBmW, and the required input power before the two-stage 1-5 split is 29dBm. Since the peak power emitted by the signal processing board is -2dBm, it is necessary to connect a driving amplifier module 501. The specific transmission signal flow is as follows Fig.26 In order to ensure the phase consistency between the channels as much as possible, the solution of using the same driving power amplifier to branch to 100 channels has high phase consistency. No other amplifier devices are introduced into the branch link, only passive power division is used, and the phase consistency is easy to control.

[0104] In some embodiments, Fig.26 and Fig.28As shown, the thermal design is carried out according to the installation space and conditions of the power amplifier component 50. The heat of the power amplifier component 50 mainly comes from the final power division module 502. The final power division module 502 adopts a modular design. The final power amplifier chip is closely fitted through its own substrate and the heat sink box 504 of the whole machine. The power amplifier component 50 is fitted with a heat dissipation cold plate and a fan 60 to dissipate heat. The main heat exchange mode of the equipment is forced convection and radiation. The whole machine including the radiator is made of aluminum, which has a high thermal conductivity, good strength and economy. At the same time, the surface is blackened to increase the emissivity ε. The surface emissivity ε after blackening can reach more than 0.9. The power amplifier adopts a stacked installation design, separated by a heat dissipation cold plate in the middle, and 100 power amplifier components 50 are divided into four groups. Each group of 25 is designed to dissipate heat to avoid the concentration of heat caused by stacking too many power amplifier components 50. The surface finish of the contact surface between the power amplifier component 50 and the heat dissipation cold plate is improved as much as possible, and the contact surface is coated with high-performance thermal conductive silicone grease to reduce thermal resistance.

[0105] Since the power amplifier generates a large amount of heat, the heat dissipation area of ​​its own structure alone cannot meet the needs of long-term tooling. Therefore, six 200×200×60 DC cooling fans 60 are added in the direction of the cold plate air duct for forced convection cooling.

[0106] The digital model of the structural design is simplified, and the power amplifier component 50 and the heat dissipation system model are created respectively, and the grid is divided for analysis. In order to facilitate the observation of the model, some structures have been wireframed. The simulation model of the main shell of the single machine is as follows Fig. 27 and Fig.28 shown.

[0107] It is known that the input heat consumption of a single transmitting power amplifier is 42W, the heat consumption of a 25-channel power amplifier is 1050W, and the heat consumption of a 100-channel power amplifier is 4200W. The temperature change of the power amplifier component 50 in the unit time is simulated at an ambient temperature of 55°C. Preliminary calculation shows that the heat dissipation area of ​​the power amplifier component 50 is not enough for natural heat dissipation. Therefore, a heat dissipation solution of designing air ducts, adding cooling fans 60, and forced convection is adopted. The solution mainly uses forced convection and heat conduction as the main heat dissipation pathways. In heat conduction, the heat dissipation area is increased and the thermal resistance on the heat source conduction path is reduced for optimization. In forced convection, the cooling fan 60 is added, the heat dissipation air duct is optimized, the wind pressure is reduced, and the heat dissipation efficiency is increased for optimization. The thermal conductivity of the material is set, and the contact thermal resistance is set between the heat source and the carrier. The solution domain is set to the ambient temperature and the convection coefficient for simulation. The temperature cloud map distribution of the power amplifier component 50 after simulation is as follows: Figure 29-Figure 31 shown.

[0108] Table 4 Temperature results of 55℃ power amplifier treatment

[0109]

[0110] The maximum temperature of the power amplifier pipeline is shown in Table 4. The fan draws away a lot of heat. The maximum operating temperature of the power amplifier chip is 90.8℃, which is lower than the maximum operating temperature of the device by 225℃. The temperature difference between the heat source and the shell is small, which means that the thermal resistance of the conduction path is small. The fan 60 wind pressure is small, which is within the normal working area, indicating that the internal air duct design is reasonable, the temperature inside the structure is uniform, and the heat dissipation structure is stable and reliable.

[0111] It can be seen that the present application discloses an S-band phased array antenna. In the present application, the array antenna is arranged on an adjustment platform, and the inclination angle of the array antenna can be flexibly adjusted through the adjustment platform, so as to facilitate the flexible application of the array antenna, and the power amplifier component is electrically connected through the antenna connecting harness, the intermediate harness and the power amplifier connecting harness, so that the array antenna can be separated from the power amplifier component for use, which can set the power amplifier component separately in a safe position to prevent the power amplifier component from being damaged by foreign objects along with the array antenna, which greatly reduces the possibility of damage to the power amplifier component, thereby reducing the cost of using the phased array antenna.

[0112] The above are merely embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structural transformations made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An S-band phased array antenna, characterized in that: It includes an array antenna, an adjustment platform, an antenna connection harness, an intermediate harness, a power amplifier connection harness and a power amplifier assembly; the array antenna is arranged on the adjustment platform, and the adjustment platform can adjust the inclination angle of the array antenna, the two ends of the intermediate harness are respectively connected to one end of the antenna connection harness and the power amplifier connection harness, the other end of the antenna connection harness is connected to the array antenna, and the other end of the power amplifier connection harness is connected to the power amplifier assembly; the antenna connection harness and the antenna connection harness are respectively used to connect the connection ports of the array antenna and the power amplifier assembly to the intermediate harness; the intermediate harness is used to increase the distance between the array antenna and the power amplifier assembly, and the array antenna includes multiple intermediate plates, and multiple antenna units are arranged on the intermediate plates, and the antenna units are symmetrically distributed in the longitudinal and transverse directions.

2. The S-band phased array antenna according to claim 1, characterized in that: The array antenna also includes an outer cover, which covers the periphery of the middle plate. The outer cover is a three-layer structure, which includes an outer layer, a middle layer and an inner layer in sequence. The inner layer is adjacent to the middle plate. The inner layer and the outer layer are made of epoxy resin quartz cloth, and the middle layer is made of hard foam.

3. The S-band phased array antenna according to claim 2, characterized in that: The thickness of the outer cover is determined based on the comprehensive wave transmittance, and the calculation formula of the comprehensive wave transmittance η1 is as follows: Where: S 21 is the transmission coefficient of the incident wave power through the outer cover, Ω is the airspace of the array coordinate system in the phased array antenna, Ω1 is the airspace of the geodetic coordinate system, θ is the incident angle of the plane wave, θ∈(0°,35°), is the projection vector of the target direction vector on the XOY plane and the angle between the X axis, 4. The S-band phased array antenna according to claim 3, characterized in that: The thickness of each layer of quartz cloth in the epoxy resin quartz cloth is 0.3mm-0.8mm, and the thickness of the inner layer and the outer layer is 0.6mm-3mm; the relative dielectric constant of the quartz cloth is 3.8, and the relative dielectric constant of the hydroamine is 3.3; the thickness of the middle layer is 1mm-5mm, and the relative dielectric constant of the middle layer is 1.02-1.

06.

5. The S-band phased array antenna according to claim 1, characterized in that: The adjustment platform comprises a support column, a base, a first direction rotating motor and a second direction rotating motor; the first direction rotating motor is arranged on the support column, driving the base to rotate along the first direction, so as to change the inclination angle of the array antenna; the second direction rotating motor is arranged on the base, and the second direction rotating motor is connected to the array antenna, driving the array antenna to rotate along the second direction, so as to change the rotation angle of the array antenna.

6. The S-band phased array antenna according to claim 5, characterized in that: The intermediate wiring harness is a hard cable assembly, and the antenna connection wiring harness and the power amplifier connection wiring harness are soft cable assemblies.

7. The S-band phased array antenna according to claim 6, characterized in that: The hard cable assembly and the soft cable assembly are both corrugated tube cables, and the hard cable assembly and the soft cable assembly are connected via a butt connector.

8. The S-band phased array antenna according to claim 7, characterized in that: The hard cable assembly is arranged in a U-shaped square tube, the U-shaped square tube includes a cover plate, and a receiving space is provided between the cover plate and the U-shaped square tube. The corrugated tube cables are stacked in sequence in the receiving space of the U-shaped square tube.

9. The S-band phased array antenna according to claim 8, characterized in that: The array antenna includes a plurality of convergent housings, the connection wires of the antenna units are connected to a connector through the convergent housings, and the connector is connected to the hard cable assembly.

10. The S-band phased array antenna according to claim 1, characterized in that: The power amplifier component includes an amplifying module, multiple power dividing modules and multiple transmitting modules. The amplifying module is electrically connected to the array antenna through the antenna connecting harness, the intermediate harness and the power amplifier connecting harness. The amplifying module is used to amplify the signal of the array antenna; the power dividing module is electrically connected to the amplifying module and the transmitting module, and is used to evenly distribute the amplified signal to the transmitting module.

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