A single-pulse VICTS phased array antenna

Abstract

The present invention discloses a single-pulse VICTS phased array antenna, comprising a radiation layer, a parallel plate waveguide layer and a feed network layer arranged from top to bottom. The feed network layer is used to access four identical TE mode wave signals and perform feed processing on the four identical TE mode wave signals to obtain four different TEM mode wave signals, namely a sum beam, an elevation difference beam, an azimuth difference wave velocity and a matching load, which are output to the parallel plate waveguide layer. The parallel plate waveguide layer is used to transmit the four different TEM mode wave signals input therein to the radiation layer, and the radiation layer is used to radiate the four different TEM mode wave signals input therein into free space. The antenna has the advantage of effectively combining the measurement accuracy of the single-pulse technology with the flexibility of the VICTS phased array antenna, being able to simultaneously and quickly and flexibly realize beam scanning in the upper half space of the antenna, while having a relatively fast tracking speed and a relatively high tracking accuracy.

Description

Technical Field

[0001] The present invention relates to a VICTS phased array antenna, in particular to a single-pulse VICTS phased array antenna. Background Art

[0002] The CTS (Continuous Transverse Stub) array antenna was first proposed by Raytheon in the 1990s, and subsequently developed into a large number of planar antenna structures. As a further evolution of the CTS antenna array, VICTS (Variable Inclination Continuous Transverse Stub) technology inherits the original high efficiency and achieves a low-profile, low-power, and mechanically robust two-dimensional beam-scanning array.

[0003] The VICTS phased array antenna primarily consists of an upper radiating CTS disk and a lower feed network disk. The radio waves propagate between the layers via air conduction, minimizing impedance losses and significantly improving radiation efficiency. The VICTS phased array antenna achieves two-dimensional beam scanning by mechanically rotating the upper radiating CTS disk and the lower feed network disk at unequal speeds in the horizontal plane, thereby aligning the antenna's beam pointing with that of the satellite. During real-time satellite tracking, the VICTS phased array antenna typically employs tracking methods such as step or conical scanning. While these methods offer high tracking speeds, they suffer from low tracking accuracy.

[0004] To achieve higher tracking accuracy, traditional parabolic antennas use a single pulse tracking method. This method uses multiple beams of the antenna to simultaneously transmit a pulse signal and compare the relative amplitude or phase of the received signals in each beam to achieve more accurate tracking. However, due to the large moment of inertia of the parabolic antenna dish, it is difficult to achieve faster rotation and higher tracking speeds, resulting in generally low tracking speeds.

[0005] Therefore, based on the VICTS antenna theory and combined with the basic principles of single-pulse tracking, it is of great significance to design a single-pulse VICTS phased array antenna with both fast tracking speed and high tracking accuracy. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a single-pulse VICTS phased array antenna with both faster tracking speed and higher tracking accuracy.

[0007] The technical solution adopted by the present invention to solve the above technical problems is: a single pulse VICTS phased array antenna, comprising a radiation layer, a parallel plate waveguide layer and a feed network layer arranged from top to bottom, the feed network layer is used to access four identical TE mode wave signals, and feed the four identical TE mode wave signals to obtain four different TEM mode wave signals, namely, a sum beam, an elevation difference beam, an azimuth difference beam and a matching load, and output them to the parallel plate waveguide layer; the parallel plate waveguide layer is used to transmit the four different TEM mode wave signals input therein to the radiation layer; the radiation layer is used to transmit the four different TEM mode wave signals input therein to the radiation layer. Four different TEM mode wave signals are radiated into free space; the radiation layer includes a first circular metal plate and a radiation unit arranged on the first circular metal plate, the radiation unit includes n CTS radiation branches evenly spaced from front to back, n is an integer greater than or equal to 2, and the center distance between each two adjacent CTS radiation branches is 11.2 mm; the parallel plate waveguide layer includes a second circular metal plate and a parallel plate waveguide structure arranged on the second circular metal plate, the parallel plate waveguide structure includes a first parallel plate waveguide and a second parallel plate waveguide with the same structural size, the The first parallel plate waveguide and the second parallel plate waveguide are respectively realized by grooving the second circular metal plate. The first parallel plate waveguide and the second parallel plate waveguide are arranged at intervals in front and back, and the second parallel plate waveguide is located on the rear side of the first parallel plate waveguide. The height of the first parallel plate waveguide is within the range of 1 / 4 wavelength to 1 / 2 wavelength in the operating frequency band of the single-pulse VICTS phased array antenna. The lower surface of the first parallel plate waveguide is provided with a first slow-wave structure, and the lower surface of the second parallel plate waveguide is provided with a second slow-wave structure. The first slow-wave structure and the The second slow-wave structure has the same structural dimensions and is respectively realized by grooving the second circular metal plate. The upper surfaces of the first parallel plate waveguide and the second parallel plate waveguide are flush with the upper surface of the second circular metal plate. The heights of the first parallel plate waveguide and the first slow-wave structure are less than the height of the second circular metal plate. The first slow-wave structure, the second slow-wave structure and the radiation layer cooperate to control the starting beam pointing of the single-pulse VICTS phased array antenna, so that the beam pointing of the single-pulse VICTS phased array antenna starts from the normal direction.The feed network layer includes a third circular metal plate and a feed network unit arranged on the third circular metal plate, the feed network unit includes a first line source, a second line source, a third line source, a fourth line source and a sum and difference feed network, the first line source, the second line source, the third line source and the fourth line source have the same structure, the first line source, the second line source, the third line source and the fourth line source are respectively used to convert TE mode waves into quasi-TEM mode wave outputs, wherein the first line source and the second line source are arranged in parallel and spaced apart on the left and right, the quasi-TEM mode waves output by the first line source and the second line source are used to excite the first parallel plate waveguide, the third line source and the fourth line source are arranged in parallel on the left and right The quasi-TEM mode waves output by the third line source and the fourth line source are used to excite the second parallel plate waveguide; the sum and differential feeding network is implemented by a quasi-planar waveguide structure, including 4 input ports, 4 output ports, 2 phase compensators, 4 90° couplers and 4 90° phase shifters, each of the 90° couplers is implemented by an E-plane waveguide branch line coupler structure, and each of the 90° phase shifters is implemented by an E-plane waveguide transmission line structure of equal length and unequal width. The four input ports of the sum and differential feeding network are connected to four identical TE mode wave signals in a one-to-one correspondence, and the four output ports of the sum and differential feeding network are connected to the first line source, the second line source, the third line source and the fourth line source in a one-to-one correspondence;Each of the phase compensators has an input end and an output end, each of the 90° phase shifters has an input end and an output end, each of the 90° couplers has a first input end, a second input end, a first output end and a second output end, the four input ports are respectively referred to as the first input port, the second input port, the third input port and the fourth input port, the four output ports are respectively referred to as the first output port, the second output port, the third output port and the fourth output port, the two phase compensators are respectively referred to as the first phase compensator and the second phase compensator, the four 90° couplers are respectively referred to as the first 90° coupler, the second 90° coupler, the third 90° coupler and the fourth 90° coupler, the four 90° phase shifters are respectively referred to as the first 90° phase shifter, The second 90° phase shifter, the third 90° phase shifter and the fourth 90° phase shifter, the first input port is connected to the input end of the first 90° phase shifter, the output end of the first 90° phase shifter is connected to the first input end of the first 90° coupler, the second input port is connected to the second input end of the first 90° coupler, the third input port is connected to the input end of the first phase compensator, the output end of the first phase compensator is connected to the input end of the second 90° phase shifter, the output end of the second 90° phase shifter is connected to the first input end of the second 90° coupler, the fourth input port is connected to the input end of the second phase compensator, the output end of the second phase compensator is connected to The second input end of the second 90° coupler is connected, the first output end of the first 90° coupler is connected to the input end of the third 90° phase shifter, the output end of the third 90° phase shifter is connected to the first input end of the third 90° coupler, the second output end of the first 90° coupler is connected to the input end of the fourth 90° phase shifter, the output end of the fourth 90° phase shifter is connected to the first input end of the fourth 90° coupler, the first output end of the second 90° coupler is connected to the second input end of the third 90° coupler, the second output end of the second 90° coupler is connected to the second input end of the fourth 90° coupler, and the third 90° coupler is connected to the input end of the fourth 90° coupler. The first output end of the coupler is connected to the first output port, the second output end of the third 90° coupler is connected to the second output port, the first output end of the fourth 90° coupler is connected to the third output port, and the second output end of the fourth 90° coupler is connected to the fourth output port; when the four input ports of the sum and differential feed network are connected to four identical TE mode wave signals in one-to-one correspondence, the TE mode wave signal connected to the first input port is called the first TE mode wave signal, the TE mode wave signal connected to the second input port is called the second TE mode wave signal, the TE mode wave signal connected to the third input port is called the third TE mode wave signal, and the TE mode wave signal connected to the fourth input port is called the fourth TE mode wave signal;The first TE mode wave signal is subjected to 90° phase shifting by the first 90° phase shifter to obtain a first phase-shifted signal having the same amplitude as the first TE mode wave signal and a phase difference of 90°, which is output to the first input end of the first 90° coupler. The second TE mode wave signal is directly transmitted to the second input end of the first 90° coupler. The first 90° coupler couples the second TE mode wave signal and the first phase-shifted signal to obtain a sum signal of the first phase-shifted signal and the second TE mode wave signal and a difference signal of the first phase-shifted signal and the second TE mode wave signal. The sum signal obtained at this time is referred to as the upper two-way sum signal, and the difference signal obtained at this time is referred to as the upper two-way difference signal. The upper two-way sum signal is directly transmitted to the second input end of the first 90° coupler. The first output end of the first 90° coupler is output, and the two difference signals are output at the second output end of the first 90° coupler; the third TE mode wave signal is phase-compensated by the first phase compensator to obtain a first phase correction signal, which is output to the second 90° phase shifter for 90° phase shifting to obtain a second phase-shifted signal with the same amplitude as the third TE mode wave signal and a phase difference of 90°, which is output to the first input end of the second 90° coupler; the fourth TE mode wave signal is phase-compensated by the second phase compensator to obtain a second phase correction signal, which is output to the second input end of the second 90° coupler, and the second 90° coupler performs 90° phase shifting on the second phase-shifted signal. The upper two-way sum signal is coupled with the second phase-corrected signal to obtain a sum signal of the second phase-shifted signal and the second phase-corrected signal and a difference signal of the second phase-shifted signal and the second phase-corrected signal. The sum signal obtained at this time is called the lower two-way sum signal, and the difference signal obtained at this time is called the lower two-way difference signal. The lower two-way sum signal is output at the first output end of the second 90° coupler, and the lower two-way difference signal is output at the second output end of the second 90° coupler; the upper two-way sum signal is subjected to 90° phase shifting by the third 90° phase shifter to obtain a third phase-shifted signal with the same amplitude as the upper two-way sum signal and a phase difference of 90°, which is output to the first input end of the third 90° coupler; the lower two-way sum signal is output to the first input end of the third 90° coupler; The signal is directly transmitted to the second input end of the third 90° coupler, and the third 90° coupler couples the third phase-shifted signal and the lower two sum signals to obtain a sum signal and a difference signal of the third phase-shifted signal and the lower two sum signals. The sum signal is output to the first line source through the first output port for conversion to obtain a sum beam output, and the difference signal is output to the second line source through the second output port for conversion to obtain a pitch difference beam output; the upper two difference signals are phase-shifted by 90° through the fourth 90° phase shifter to obtain a fourth phase-shifted signal with the same amplitude as the upper two difference signals and a phase difference of 90°, which is output to the first input end of the fourth 90° coupler;The lower two difference signals are directly transmitted to the second input end of the fourth 90° coupler. The fourth 90° coupler couples the fourth phase-shifted signal and the lower two difference signals to obtain a sum signal and a difference signal of the fourth phase-shifted signal and the lower two difference signals. The sum signal is output to the third line source through the third output port for conversion to obtain an azimuth difference wave velocity output. The difference signal is output to the fourth line source through the fourth output port for conversion to obtain a matched load output.

[0008] Compared with the prior art, the advantage of the present invention is that a single-pulse VICTS phased array antenna is formed by a radiation layer, a parallel plate waveguide layer and a feeding network layer arranged from top to bottom, the feeding network layer is used to access four identical TE mode wave signals, and feed the four identical TE mode wave signals to obtain four different TEM mode wave signals, namely, a sum beam, an elevation difference beam, an azimuth difference beam and a matching load, and output them to the parallel plate waveguide layer, the parallel plate waveguide layer is used to transmit the four different TEM mode wave signals input therein to the radiation layer, and the radiation layer is used to radiate the four different TEM mode wave signals input therein into free space; the radiation layer includes a first circular metal plate and a radiation unit arranged on the first circular metal plate, the radiation unit includes n CTS radiation branches evenly spaced in order from front to back, n is an integer greater than or equal to 2, and the center distance between each two adjacent CTS radiation branches is 11.2 mm; the parallel plate waveguide layer includes a second circular metal plate and a parallel plate waveguide structure arranged on the second circular metal plate, the parallel plate waveguide structure includes structures with the same size a first parallel plate waveguide and a second parallel plate waveguide, the first parallel plate waveguide and the second parallel plate waveguide are respectively realized by making grooves on the second circular metal plate, the first parallel plate waveguide and the second parallel plate waveguide are arranged at intervals in front and back, and the second parallel plate waveguide is located on the rear side of the first parallel plate waveguide, the height of the first parallel plate waveguide is within the range of 1 / 4 wavelength to 1 / 2 wavelength in the operating frequency band of the single-pulse VICTS phased array antenna, the lower surface of the first parallel plate waveguide is provided with a first slow-wave structure, the lower surface of the second parallel plate waveguide is provided with a second slow-wave structure, the structural dimensions of the first slow-wave structure and the second slow-wave structure are the same, and are respectively realized by making grooves on the second circular metal plate, the upper surfaces of the first parallel plate waveguide and the second parallel plate waveguide are flush with the upper surface of the second circular metal plate, and the heights of the first parallel plate waveguide and the first slow-wave structure are less than the height of the second circular metal plate; the first slow-wave structure, the second slow-wave structure and the radiation layer cooperate to control the starting beam pointing of the single-pulse VICTS phased array antenna, so that the beam pointing of the single-pulse VICTS phased array antenna starts from the normal direction;The feeding network layer includes a third circular metal plate and a feeding network unit arranged on the third circular metal plate, the feeding network unit includes a first line source, a second line source, a third line source, a fourth line source and a sum and difference feeding network, the first line source, the second line source, the third line source and the fourth line source have the same structure, the first line source, the second line source, the third line source and the fourth line source are respectively used to convert TE mode waves into quasi-TEM mode wave outputs, wherein the first line source and the second line source are arranged in parallel and spaced apart on the left and right, the quasi-TEM mode waves output by the first line source and the second line source are used to excite the first parallel plate waveguide, so that the quasi-TEM mode waves output by the first parallel plate waveguide can be transmitted to the radiation layer with low loss and no distortion, the third line source and the fourth line source are arranged in parallel and spaced apart on the left and right, and the third line source and the fourth line source are arranged in parallel and spaced apart on the left and right. The quasi-TEM mode wave output by the four-line source is used to excite the second parallel plate waveguide, so that the quasi-TEM mode wave output by the second parallel plate waveguide can be transmitted to the radiation layer with low loss and no distortion; the sum and differential feeding network is implemented by a quasi-planar waveguide structure, including 4 input ports, 4 output ports, 2 phase compensators, 4 90° couplers and 4 90° phase shifters, each 90° coupler is implemented by an E-plane waveguide branch line coupler structure, and each 90° phase shifter is implemented by an E-plane waveguide transmission line structure of equal length and unequal width. The four input ports of the sum and differential feeding network are connected to four identical TE mode wave signals in a one-to-one correspondence, and the four output ports of the sum and differential feeding network are connected to the first line source, the second line source, the third line source and the fourth line source in a one-to-one correspondence;Each phase compensator has an input end and an output end, each 90° phase shifter has an input end and an output end, each 90° coupler has a first input end, a second input end, a first output end, and a second output end, the four input ports are respectively referred to as the first input port, the second input port, the third input port, and the fourth input port, the two phase compensators are respectively referred to as the first phase compensator and the second phase compensator, the four 90° couplers are respectively referred to as the first 90° coupler, the second 90° coupler, the third 90° coupler, and the fourth 90° coupler, the four 90° phase shifters are respectively referred to as the first 90° phase shifter, the second 90° phase shifter, and the fourth 90° coupler. a phase shifter, a third 90° phase shifter, and a fourth 90° phase shifter; a first input port connected to the input end of the first 90° phase shifter; an output end of the first 90° phase shifter connected to the first input end of the first 90° coupler; a second input port connected to the second input end of the first 90° coupler; a third input port connected to the input end of the first phase compensator; an output end of the first phase compensator connected to the input end of the second 90° phase shifter; an output end of the second 90° phase shifter connected to the first input end of the second 90° coupler; a fourth input port connected to the input end of the second phase compensator; an output end of the second phase compensator connected to the second 90° coupler; The first input end of the first 90° coupler is connected to the second input end of the third 90° phase shifter, the output end of the third 90° phase shifter is connected to the first input end of the third 90° coupler, the second output end of the first 90° coupler is connected to the input end of the fourth 90° phase shifter, the output end of the fourth 90° phase shifter is connected to the first input end of the fourth 90° coupler, the first output end of the second 90° coupler is connected to the second input end of the third 90° coupler, the second output end of the second 90° coupler is connected to the second input end of the fourth 90° coupler, and the first output end of the third 90° coupler is connected to the first output end. The first output port of the sum and differential feed network is connected to the first output port, the second output port of the third 90° coupler is connected to the second output port, the first output port of the fourth 90° coupler is connected to the third output port, and the second output port of the fourth 90° coupler is connected to the fourth output port; when the four input ports of the sum and differential feed network are connected to four identical TE mode wave signals in one-to-one correspondence, the TE mode wave signal connected to the first input port is called the first TE mode wave signal, the TE mode wave signal connected to the second input port is called the second TE mode wave signal, the TE mode wave signal connected to the third input port is called the third TE mode wave signal, and the TE mode wave signal connected to the fourth input port is called the fourth TE mode wave signal;The first TE mode wave signal is subjected to 90° phase shifting by the first 90° phase shifter to obtain a first phase-shifted signal having the same amplitude as the first TE mode wave signal and a phase difference of 90°, which is output to the first input end of the first 90° coupler. The second TE mode wave signal is directly transmitted to the second input end of the first 90° coupler. The first 90° coupler couples the second TE mode wave signal and the first phase-shifted signal to obtain a sum signal of the first phase-shifted signal and the second TE mode wave signal and a difference signal of the first phase-shifted signal and the second TE mode wave signal. The sum signal obtained at this time is called the upper two-way sum signal, and the difference signal obtained at this time is called the upper two-way difference signal. The sum signal of the two paths is output at the first output end of the first 90° coupler, and the difference signal of the two paths is output at the second output end of the first 90° coupler; the third TE mode wave signal is phase-compensated by the first phase compensator to obtain a first phase correction signal, which is output to the second 90° phase shifter for 90° phase shifting, and then a second phase-shifted signal with the same amplitude as the third TE mode wave signal and a phase difference of 90° is obtained, which is output to the first input end of the second 90° coupler; the fourth TE mode wave signal is phase-compensated by the second phase compensator to obtain a second phase correction signal, which is output to the second input end of the second 90° coupler, and the second 90° coupler performs 90° phase shifting on the second TE mode wave signal. The upper two-way sum signal is coupled with the second phase-corrected signal to obtain a sum signal of the second phase-shifted signal and the second phase-corrected signal and a difference signal of the second phase-shifted signal and the second phase-corrected signal. The sum signal obtained at this time is called the lower two-way sum signal, and the difference signal obtained at this time is called the lower two-way difference signal. The lower two-way sum signal is output at the first output end of the second 90° coupler, and the lower two-way difference signal is output at the second output end of the second 90° coupler; the upper two-way sum signal is phase-shifted by 90° through the third 90° phase shifter to obtain a third phase-shifted signal with the same amplitude as the upper two-way sum signal and a phase difference of 90°, which is output to the first input end of the third 90° coupler. The lower two sum signals are directly transmitted to the second input end of the third 90° coupler, and the third 90° coupler couples the third phase-shifted signal and the lower two sum signals to obtain a sum signal and a difference signal of the third phase-shifted signal and the lower two sum signals. The sum signal is output to the first line source through the first output port for conversion to obtain a sum beam output, and the difference signal is output to the second line source through the second output port for conversion to obtain a pitch difference beam output; the upper two difference signals are phase-shifted by 90° through the fourth 90° phase shifter to obtain a fourth phase-shifted signal with the same amplitude as the upper two difference signals and a phase difference of 90°, which is output to the first input end of the fourth 90° coupler;The lower two difference signals are directly transmitted to the second input end of the fourth 90° coupler, and the fourth 90° coupler couples the fourth phase-shifted signal and the lower two difference signals to obtain the sum signal and the difference signal of the fourth phase-shifted signal and the lower two difference signals. The sum signal is output to the third line source through the third output port for conversion to obtain an azimuth difference beam output, and the difference signal is output to the fourth line source through the fourth output port for conversion to obtain a matched load output; in the present invention, the first parallel plate waveguide is connected to the first line source and the second line source respectively, and the second parallel plate waveguide is connected to the third line source and the fourth line source respectively. The two parallel plate waveguides of the first parallel plate waveguide and the second parallel plate waveguide correspond to the four line sources of the first line source, the second line source, the third line source and the fourth line source, and the sum and difference feeding networks respectively control the phase changes of the signals of each line source. The VICTS antenna of the present invention is essentially Divided into four subarrays, the radiating layer radiates signals into space through CTS radiating branches. This is achieved using a series feed method, with the first and second parallel plate waveguides stimulating the CTS radiating branches. This causes the required phases of the four subarrays to change with frequency. Each subarray is phase-compensated via phase shifters cascaded between the sum and difference feed networks. The four subarrays deliver the required sum beam, elevation difference beam, azimuth difference beam, and matching load signals for four different TEM mode wave signals. The radiating layer and the parallel plate waveguide layer mechanically rotate relative to each other at unequal speeds in the horizontal plane to achieve beam scanning across the upper hemisphere of the antenna. This effectively combines the measurement accuracy of single-pulse technology with the flexibility of VICTS phased array antennas, enabling rapid and flexible beam scanning across the antenna's upper half-space while maintaining high tracking speed and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 A burst diagram of a single-pulse VICTS phased array antenna of the present invention;

[0010] Figure 2 A top view of a parallel plate waveguide layer of a single-pulse VICTS phased array antenna of the present invention;

[0011] Figure 3 A top view of a feed network layer of a single-pulse VICTS phased array antenna of the present invention;

[0012] Figure 4 A schematic diagram of a sum and difference feed network for a single-pulse VICTS phased array antenna according to the present invention;

[0013] Figure 5 A beam pointing curve diagram of a single-pulse VICTS phased array antenna of the present invention;

[0014] Figure 6 It is the normalized sum and difference pattern of a single-pulse VICTS phased array antenna rotated 0° according to the present invention;

[0015] Figure 7 It is the normalized sum and difference pattern of a single-pulse VICTS phased array antenna rotated 20° according to the present invention;

[0016] Figure 8 This is the normalized sum and difference pattern of a single-pulse VICTS phased array antenna rotated 40° according to the present invention. DETAILED DESCRIPTION

[0017] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0018] Example: Figures 1 to 4A single-pulse VICTS phased array antenna is shown, comprising a radiating layer 1, a parallel plate waveguide layer 2, and a feed network layer 3 arranged from top to bottom. The feed network layer 3 receives four identical TE mode wave signals and feeds them to generate four different TEM mode wave signals: sum beam, elevation difference beam, azimuth difference velocity, and matched load. These signals are then output to the parallel plate waveguide layer 2. The parallel plate waveguide layer 2 transmits the four different TEM mode wave signals input therein to the radiating layer 1, which radiates the four different TEM mode wave signals into free space. The radiating layer 1 comprises a first circular metal plate 4 and a radiating element disposed thereon. The radiating element comprises n CTS radiating branches 5 evenly spaced from front to back, where n is an integer greater than or equal to 2, and the center-to-center distance between two adjacent CTS radiating branches 5 is 11.2mm; the parallel plate waveguide layer 2 includes a second circular metal plate 6 and a parallel plate waveguide structure arranged on the second circular metal plate 6, the parallel plate waveguide structure includes a first parallel plate waveguide 7 and a second parallel plate waveguide 8 with the same structural dimensions, the first parallel plate waveguide 7 and the second parallel plate waveguide 8 are respectively realized by grooving on the second circular metal plate 6, the first parallel plate waveguide 7 and the second parallel plate waveguide 8 are arranged at intervals in front and behind, and the second parallel plate waveguide 8 is located on the rear side of the first parallel plate waveguide 7, the height of the first parallel plate waveguide 7 is within the range of 1 / 4 wavelength to 1 / 2 wavelength under the working frequency band of the single-pulse VICTS phased array antenna, the lower surface of the first parallel plate waveguide 7 is provided with a first slow-wave structure, and the lower surface of the second parallel plate waveguide 8 is provided with a second slow-wave structure, the structural dimensions of the first slow-wave structure and the second slow-wave structure are the same, and are respectively realized by grooving on the second circular metal plate 6, the upper surfaces of the first parallel plate waveguide 7 and the second parallel plate waveguide 8 are flush with the upper surface of the second circular metal plate 6, and the height of the first parallel plate waveguide 7 and the first slow-wave structure is less than that of the second circular metal plate 6 The first slow-wave structure, the second slow-wave structure and the radiation layer 1 cooperate to control the starting beam pointing of the single-pulse VICTS phased array antenna, so that the beam pointing of the single-pulse VICTS phased array antenna starts from the normal direction; the feed network layer 3 includes a third circular metal plate 9 and a feed network unit arranged on the third circular metal plate 9, the feed network unit includes a first line source 10, a second line source 11, a third line source 12, a fourth line source 13 and a sum and difference feeding network, the first line source 10, the second line source 11, the third line source 1 2 and fourth line sources 13 have the same structure. The first line source 10, second line source 11, third line source 12, and fourth line source 13 are respectively used to convert TE mode waves into quasi-TEM mode waves for output. The first line source 10 and second line source 11 are arranged in parallel and spaced apart. The quasi-TEM mode waves output by the first line source 10 and second line source 11 are used to excite the first parallel plate waveguide 7. The third line source 12 and fourth line source 13 are arranged in parallel and spaced apart. The quasi-TEM mode waves output by the third line source 12 and fourth line source 13 are used to excite the second parallel plate waveguide 8.

[0019] The sum and difference feeding network is implemented using a quasi-planar waveguide structure, including four input ports, four output ports, two phase compensators, four 90° couplers and four 90° phase shifters. Each 90° coupler is implemented using an E-plane waveguide branch line coupler structure, and each 90° phase shifter is implemented through an E-plane waveguide transmission line structure of equal length and unequal width. The four input ports of the sum and difference feeding network are connected to four identical TE mode wave signals in a one-to-one correspondence, and the four output ports of the sum and difference feeding network are connected to the first line source 10, the second line source 11, the third line source 12 and the fourth line source 13 in a one-to-one correspondence.Each phase compensator has an input end and an output end, each 90° phase shifter has an input end and an output end, each 90° coupler has a first input end, a second input end, a first output end and a second output end, the four input ports are respectively referred to as the first input port in1, the second input port in2, the third input port in3 and the fourth input port in4, the four output ports are respectively referred to as the first output port out1, the second output port out2, the third output port out3 and the fourth output port out4, the two phase compensators are respectively referred to as the first phase compensator 15 and the second phase compensator 16, the four 90° couplers are respectively referred to as the first 90 90° coupler 17, second 90° coupler 18, third 90° coupler 19 and fourth 90° coupler 20, the four 90° phase shifters are respectively called first 90° phase shifter 21, second 90° phase shifter 22, third 90° phase shifter 23 and fourth 90° phase shifter 24, the first input port in1 is connected to the input end of the first 90° phase shifter 21, the output end of the first 90° phase shifter 21 is connected to the first input end of the first 90° coupler 17, the second input port in2 is connected to the second input end of the first 90° coupler 17, the third input port in3 is connected to the input end of the first phase compensator 15, and the output end of the first phase compensator 15 is connected to the first input end of the first 90° coupler 17. The output end of the first 90° phase shifter 23 is connected to the input end of the third 90° phase shifter 23, the output end of the third 90° phase shifter 23 is connected to the first input end of the third 90° coupler 19, the second output end of the first 90° coupler 17 is connected to the input end of the fourth 90° phase shifter 24, and the fourth 90° phase shifter 25 is connected to the output end of the second 90° phase shifter 22. An output end of the 0° phase shifter 24 is connected to a first input end of the fourth 90° coupler 20, a first output end of the second 90° coupler 18 is connected to a second input end of the third 90° coupler 19, a second output end of the second 90° coupler 18 is connected to a second input end of the fourth 90° coupler 20, a first output end of the third 90° coupler 19 is connected to a first output port out1, a second output end of the third 90° coupler 19 is connected to a second output port out2, a first output end of the fourth 90° coupler 20 is connected to a third output port out3, and a second output end of the fourth 90° coupler 20 is connected to a fourth output port out4;When the four input ports of the sum and differential feeding network are connected to four identical TE mode wave signals in one-to-one correspondence, the TE mode wave signal connected to the first input port in1 is called the first TE mode wave signal, the TE mode wave signal connected to the second input port in2 is called the second TE mode wave signal, the TE mode wave signal connected to the third input port in3 is called the third TE mode wave signal, and the TE mode wave signal connected to the fourth input port in4 is called the fourth TE mode wave signal; the first TE mode wave signal is subjected to a 90° phase shift by the first 90° phase shifter 21 to obtain a first phase shift signal having the same amplitude as the first TE mode wave signal and a phase difference of 90°. The signal is output to the first input end of the first 90° coupler 17, and the second TE mode wave signal is directly transmitted to the second input end of the first 90° coupler 17. The first 90° coupler 17 couples the second TE mode wave signal and the first phase-shifted signal to obtain a sum signal of the first phase-shifted signal and the second TE mode wave signal and a difference signal of the first phase-shifted signal and the second TE mode wave signal. The sum signal obtained at this time is called the upper two-way sum signal, and the difference signal obtained at this time is called the upper two-way difference signal. The upper two-way sum signal is output at the first output end of the first 90° coupler 17, and the upper two-way difference signal is output at the first output end of the first 90° coupler 17. The second output end is output; the third TE mode wave signal is phase-compensated by the first phase compensator 15 to obtain a first phase correction signal, which is output to the second 90° phase shifter 22 for 90° phase shifting to obtain a second phase-shifted signal with the same amplitude as the third TE mode wave signal and a phase difference of 90°, which is output to the first input end of the second 90° coupler 18; the fourth TE mode wave signal is phase-compensated by the second phase compensator 16 to obtain a second phase correction signal, which is output to the second input end of the second 90° coupler 18. The second 90° coupler 18 couples the second phase-shifted signal and the second phase correction signal. A sum signal of the second phase-shifted signal and the second phase-corrected signal and a difference signal of the second phase-shifted signal and the second phase-corrected signal are obtained. The sum signal obtained at this time is referred to as the lower two-way sum signal, and the difference signal obtained at this time is referred to as the lower two-way difference signal. The lower two-way sum signal is output at the first output end of the second 90° coupler 18, and the lower two-way difference signal is output at the second output end of the second 90° coupler 18. The upper two-way sum signal is subjected to 90° phase shifting by the third 90° phase shifter 23 to obtain a third phase-shifted signal having the same amplitude as the upper two-way sum signal and a phase difference of 90°, which is output to the first input end of the third 90° coupler 19.The lower two sum signals are directly transmitted to the second input end of the third 90° coupler 19. The third 90° coupler 19 couples the third phase-shifted signal and the lower two sum signals to obtain a sum signal and a difference signal of the third phase-shifted signal and the lower two sum signals. The sum signal is output to the first line source 10 through the first output port out1 for conversion to obtain a sum beam output. The difference signal is output to the second line source 11 through the second output port out2 for conversion to obtain a pitch difference beam output. The upper two difference signals are subjected to 90° phase shifting by the fourth 90° phase shifter 24 to obtain a beam that is aligned with the upper two difference signals. A fourth phase-shifted signal with the same amplitude and a 90° phase difference is output to the first input of a fourth 90° coupler 20. The lower two difference signals are directly transmitted to the second input of the fourth 90° coupler 20. The fourth 90° coupler 20 couples the fourth phase-shifted signal with the lower two difference signals to obtain a sum signal and a difference signal of the fourth phase-shifted signal and the lower two difference signals. The sum signal is output to the third line source 12 via a third output port out3 for conversion to obtain an azimuth difference beam output. The difference signal is output to the fourth line source 13 via a fourth output port out4 for conversion to obtain a matched load output.

[0020] By changing the relative rotation angle between the parallel plate waveguide layer and the radiation layer of the single pulse VICTS phased array antenna of the present invention, the sum beam, the elevation difference beam, and the azimuth difference beam are scanned in the upper half space of the antenna, and the following is obtained: Figure 5 The beam pointing curve is shown. Figure 5 It can be seen that: when the relative rotation angle between the parallel plate waveguide layer and the radiating layer is zero, the beam pointing of the single-pulse VICTS phased array antenna changes from the normal direction (the vertical coordinate is zero). As the relative selection angle changes, the beam pointing of the single-pulse VICTS phased array antenna also changes. Therefore, by changing the relative rotation angle between the parallel plate waveguide layer and the radiating layer, beam scanning of the sum beam, pitch difference beam, and azimuth difference beam in the upper half space of the antenna can be achieved.

[0021] The single-pulse VICTS phased array antenna of the present invention is simulated using HFSS, and the rotation angle of the single-pulse VICTS phased array antenna of the present invention is set to 0°, as shown in the following figure: Figure 6 The normalized sum and difference patterns are shown. Figure 6 In the figure, when the abscissa is zero (this value is chosen to ensure that the VICTS phased array antenna beam pointing starts in the normal direction), the sum beam SUM has only one peak, and the difference beam appears in a waveform curve symmetrically along the line where the abscissa is zero, with the abscissa being the trough. Therefore, the monopulse VICTS phased array antenna of the present invention can generate a sum beam, an elevation difference beam, and an azimuth difference beam when rotated 0°.

[0022] The single-pulse VICTS phased array antenna of the present invention is simulated using HFSS, and the rotation angle of the single-pulse VICTS phased array antenna of the present invention is set to 20°, as shown in the following figure: Figure 7 The normalized sum and difference patterns are shown. Figure 7 It can be seen that when the abscissa is zero (this value is chosen to ensure that the VICTS phased array antenna beam pointing starts in the normal direction), the sum beam SUM has only one peak, while the difference beam appears in a waveform curve symmetrically along the line where the abscissa is zero, with the abscissa being the trough. Therefore, the monopulse VICTS phased array antenna of the present invention can generate a sum beam, an elevation difference beam, and an azimuth difference beam by rotating it 20°.

[0023] The single-pulse VICTS phased array antenna of the present invention is simulated using HFSS, and the rotation angle of the single-pulse VICTS phased array antenna of the present invention is set to 40°, as shown below: Figure 8 The normalized sum and difference patterns are shown. Figure 8 It can be seen that when the abscissa is zero (this value is chosen to ensure that the VICTS phased array antenna beam pointing starts in the normal direction), the sum beam SUM has only one peak, while the difference beam appears in a waveform curve symmetrical to the line where the abscissa is zero, with the abscissa being the trough. Therefore, a 40° rotation of the pulsed VICTS phased array antenna can generate a sum beam, an elevation difference beam, and an azimuth difference beam.

Claims

1. A single-pulse VICTS phased array antenna, characterized in that The system comprises a radiation layer, a parallel plate waveguide layer and a feed network layer arranged from top to bottom. The feed network layer is used to receive four identical TE mode wave signals and perform feed processing on the four identical TE mode wave signals to obtain four different TEM mode wave signals, namely, sum beam, elevation difference beam, azimuth difference wave velocity and matching load, and output them to the parallel plate waveguide layer. The parallel plate waveguide layer is used to transmit the four different TEM mode wave signals input therein to the radiation layer. The radiation layer is used to radiate the four different TEM mode wave signals input therein into free space. The radiation layer includes a first circular metal plate and a radiation unit provided on the first circular metal plate, wherein the radiation unit includes n CTS radiation branches evenly spaced from front to back, where n is an integer greater than or equal to 2, and the center distance between each two adjacent CTS radiation branches is 11.2 mm; The parallel plate waveguide layer includes a second circular metal plate and a parallel plate waveguide structure arranged on the second circular metal plate, the parallel plate waveguide structure includes a first parallel plate waveguide and a second parallel plate waveguide with the same structural size, the first parallel plate waveguide and the second parallel plate waveguide are respectively realized by slotting the second circular metal plate, the first parallel plate waveguide and the second parallel plate waveguide are arranged in a front-to-back arrangement, and the second parallel plate waveguide is located on the rear side of the first parallel plate waveguide, the height of the first parallel plate waveguide is within the range of 1 / 4 wavelength to 1 / 2 wavelength in the operating frequency band of the single-pulse VICTS phased array antenna, and the lower surface of the first parallel plate waveguide is provided with a first slow wave structure, a second slow-wave structure is provided on the lower surface of the second parallel plate waveguide, the first slow-wave structure and the second slow-wave structure have the same structural dimensions and are respectively realized by grooving on the second circular metal plate, the upper surfaces of the first parallel plate waveguide and the second parallel plate waveguide are flush with the upper surface of the second circular metal plate, and the heights of the first parallel plate waveguide and the first slow-wave structure are less than the height of the second circular metal plate; the first slow-wave structure, the second slow-wave structure and the radiation layer cooperate to control the starting beam pointing of the single-pulse VICTS phased array antenna, so that the beam pointing of the single-pulse VICTS phased array antenna starts from the normal direction; The feed network layer includes a third circular metal plate and a feed network unit arranged on the third circular metal plate. The feed network unit includes a first line source, a second line source, a third line source, a fourth line source and a sum and difference feed network. The first line source, the second line source, the third line source and the fourth line source have the same structure. The first line source, the second line source, the third line source and the fourth line source are respectively used to convert TE mode waves into quasi-TEM mode wave outputs, wherein the first line source and the second line source are arranged in parallel and spaced apart on the left and right sides, and the quasi-TEM mode waves output by the first line source and the second line source are used to excite the first parallel plate waveguide. The third line source and the fourth line source are arranged in parallel and spaced apart on the left and right sides, and the quasi-TEM mode waves output by the third line source and the fourth line source are used to excite the second parallel plate waveguide. The sum and differential feeding network is implemented using a quasi-planar waveguide structure, including four input ports, four output ports, two phase compensators, four 90° couplers, and four 90° phase shifters. Each of the 90° couplers is implemented using an E-plane waveguide branch line coupler structure, and each of the 90° phase shifters is implemented through an E-plane waveguide transmission line structure of equal length and unequal width. The four input ports of the sum and differential feeding network are connected to four identical TE mode wave signals in a one-to-one correspondence, and the four output ports of the sum and differential feeding network are connected to the first line source, the second line source, the third line source, and the fourth line source in a one-to-one correspondence.Each of the phase compensators has an input end and an output end, each of the 90° phase shifters has an input end and an output end, each of the 90° couplers has a first input end, a second input end, a first output end and a second output end, the four input ports are respectively referred to as the first input port, the second input port, the third input port and the fourth input port, the four output ports are respectively referred to as the first output port, the second output port, the third output port and the fourth output port, the two phase compensators are respectively referred to as the first phase compensator and the second phase compensator, the four 90° couplers are respectively referred to as the first 90° coupler, the second 90° coupler, the third 90° coupler and the fourth 90° coupler, the four 90° phase shifters are respectively referred to as the first 90° phase shifter, The second 90° phase shifter, the third 90° phase shifter and the fourth 90° phase shifter, the first input port is connected to the input end of the first 90° phase shifter, the output end of the first 90° phase shifter is connected to the first input end of the first 90° coupler, the second input port is connected to the second input end of the first 90° coupler, the third input port is connected to the input end of the first phase compensator, the output end of the first phase compensator is connected to the input end of the second 90° phase shifter, the output end of the second 90° phase shifter is connected to the first input end of the second 90° coupler, the fourth input port is connected to the input end of the second phase compensator, the output end of the second phase compensator is connected to The second input end of the second 90° coupler is connected, the first output end of the first 90° coupler is connected to the input end of the third 90° phase shifter, the output end of the third 90° phase shifter is connected to the first input end of the third 90° coupler, the second output end of the first 90° coupler is connected to the input end of the fourth 90° phase shifter, the output end of the fourth 90° phase shifter is connected to the first input end of the fourth 90° coupler, the first output end of the second 90° coupler is connected to the second input end of the third 90° coupler, the second output end of the second 90° coupler is connected to the second input end of the fourth 90° coupler, and the third 90° coupler is connected to the input end of the fourth 90° coupler. The first output end of the coupler is connected to the first output port, the second output end of the third 90° coupler is connected to the second output port, the first output end of the fourth 90° coupler is connected to the third output port, and the second output end of the fourth 90° coupler is connected to the fourth output port; when the four input ports of the sum and differential feed network are connected to four identical TE mode wave signals in one-to-one correspondence, the TE mode wave signal connected to the first input port is called the first TE mode wave signal, the TE mode wave signal connected to the second input port is called the second TE mode wave signal, the TE mode wave signal connected to the third input port is called the third TE mode wave signal, and the TE mode wave signal connected to the fourth input port is called the fourth TE mode wave signal;The first TE mode wave signal is subjected to 90° phase shifting by the first 90° phase shifter to obtain a first phase-shifted signal having the same amplitude as the first TE mode wave signal and a phase difference of 90°, which is output to the first input end of the first 90° coupler. The second TE mode wave signal is directly transmitted to the second input end of the first 90° coupler. The first 90° coupler couples the second TE mode wave signal and the first phase-shifted signal to obtain a sum signal of the first phase-shifted signal and the second TE mode wave signal and a difference signal of the first phase-shifted signal and the second TE mode wave signal. The sum signal obtained at this time is referred to as the upper two-way sum signal, and the difference signal obtained at this time is referred to as the upper two-way difference signal. The upper two-way sum signal is directly transmitted to the second input end of the first 90° coupler. The first output end of the first 90° coupler is output, and the two difference signals are output at the second output end of the first 90° coupler; the third TE mode wave signal is phase-compensated by the first phase compensator to obtain a first phase correction signal, which is output to the second 90° phase shifter for 90° phase shifting to obtain a second phase-shifted signal with the same amplitude as the third TE mode wave signal and a phase difference of 90°, which is output to the first input end of the second 90° coupler; the fourth TE mode wave signal is phase-compensated by the second phase compensator to obtain a second phase correction signal, which is output to the second input end of the second 90° coupler, and the second 90° coupler performs 90° phase shifting on the second phase-shifted signal. The upper two-way sum signal is coupled with the second phase-corrected signal to obtain a sum signal of the second phase-shifted signal and the second phase-corrected signal and a difference signal of the second phase-shifted signal and the second phase-corrected signal. The sum signal obtained at this time is called the lower two-way sum signal, and the difference signal obtained at this time is called the lower two-way difference signal. The lower two-way sum signal is output at the first output end of the second 90° coupler, and the lower two-way difference signal is output at the second output end of the second 90° coupler; the upper two-way sum signal is subjected to 90° phase shifting by the third 90° phase shifter to obtain a third phase-shifted signal with the same amplitude as the upper two-way sum signal and a phase difference of 90°, which is output to the first input end of the third 90° coupler; the lower two-way sum signal is output to the first input end of the third 90° coupler; The signal is directly transmitted to the second input end of the third 90° coupler, and the third 90° coupler couples the third phase-shifted signal and the lower two sum signals to obtain a sum signal and a difference signal of the third phase-shifted signal and the lower two sum signals. The sum signal is output to the first line source through the first output port for conversion to obtain a sum beam output, and the difference signal is output to the second line source through the second output port for conversion to obtain a pitch difference beam output; the upper two difference signals are phase-shifted by 90° through the fourth 90° phase shifter to obtain a fourth phase-shifted signal with the same amplitude as the upper two difference signals and a phase difference of 90°, which is output to the first input end of the fourth 90° coupler;The lower two difference signals are directly transmitted to the second input end of the fourth 90° coupler. The fourth 90° coupler couples the fourth phase-shifted signal and the lower two difference signals to obtain a sum signal and a difference signal of the fourth phase-shifted signal and the lower two difference signals. The sum signal is output to the third line source through the third output port for conversion to obtain an azimuth difference beam output. The difference signal is output to the fourth line source through the fourth output port for conversion to obtain a matched load output.

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