Novel planar monopulse sum-difference network based on gap waveguide structure

Abstract

The invention relates to the technical field of communication, in particular to a novel planar monopulse sum-difference network based on a gap waveguide structure, which is characterized in that the structure of the sum-difference network is a cross seven-port network, and the sum-difference network is specifically composed of three sub sum-difference devices, a gap waveguide one-to-two T-shaped power divider and a matching structure; each sub sum-difference device is composed of a planar 3dB coupling bridge and a slow-wave structure phase shifter; according to the slow wave structure phase shifter, a ridge structure is introduced into a channel on one side to change the phase velocity of the channel, the phase difference of the two channels is 90 degrees, a sub sum-difference device of an electromagnetic band gap structure is formed in cooperation with a planar 3dB coupling bridge, and addition or subtraction of two paths of signals is achieved. And the three sub sum-difference devices, the gap waveguide one-to-two T-shaped power divider and the matching structure are mutually matched to realize addition or subtraction of four paths of signals. The sum-difference network has the advantages of simple design, excellent performance, low profile, low cost and high manufacturing consistency, and can be widely applied to engineering projects.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of communication technology, in particular to a new type of planar single-pulse and difference network based on gap waveguide structure. BACKGROUND

[0002] Single-pulse radar can obtain all the distance information, azimuth coordinate information and elevation coordinate information of the target within one pulse period, and single-pulse antenna as a component of single-pulse radar has been widely concerned due to the sharp increase in application demand today. As a high-precision tracking antenna, single-pulse antenna is mainly composed of a sum-and-difference network and an antenna array. After receiving the electromagnetic wave signal, the sum-and-difference network calculates the sum beam signal, the azimuth difference beam signal and the elevation difference beam signal.

[0003] Commonly used sum-and-difference networks mostly use microstrip line structure, substrate integrated waveguide structure, or waveguide microstrip network composed of multiple magic T. The Chinese patent with publication number CN209746114U proposes a millimeter wave sum-and-difference network in the form of microstrip line. Although the microstrip line structure has low profile and simple design, it has large loss in the millimeter wave frequency band, low power capacity, and is sensitive to the dielectric constant of the microstrip board. The substrate integrated waveguide structure also has a planar structure, but the electromagnetic wave propagates completely in the dielectric region, and the insertion loss in the millimeter wave frequency band is still large, which is difficult to meet the requirements. The Chinese patent with publication number CN107317082A proposes a two-dimensional single-pulse sum-and-difference network using a multi-layer waveguide structure. This sum-and-difference network not only needs a multi-layer structure, which increases the profile and weight of the network, but also needs to be welded between layers, which increases the manufacturing cost, processing difficulty and price cycle, and the yield rate is difficult to guarantee in the millimeter wave and above frequency bands, making it difficult to be widely applied. The Chinese patent with publication number CN112748426A proposes an 8-port single-pulse sum-and-difference network based on a gap waveguide structure with a circular pin, a 3dB coupling bridge and a 90° phase shifter designed based on a metal ridge structure. However, the EBG uses a circular pin structure, which is complex to process. The 90° phase shifter used is a step structure, which is sensitive to size accuracy. Moreover, the single-pulse sum-and-difference network designed uses four sub-sum-and-difference networks, which is a complex structure.

[0004] Gap waveguide structure, as a kind of electromagnetic bandgap structure, can suppress electromagnetic waves in a specific frequency range, achieve consistent electrical performance characteristics as traditional waveguides, has the advantage of low loss of waveguide structure, and does not need welding, which is easy to assemble and integrate with the antenna array.

[0005] However, domestic and foreign research teams have not established a connection between gap waveguide structure and sum-and-difference network, and there is no mature sum-and-difference network based on gap waveguide structure in use. SUMMARY

[0006] In order to solve the above technical problems, the embodiment of the present application proposes a new type of planar monopulse sum and difference network based on gap waveguide structure, which has the advantages of simple design, excellent performance, low profile, low cost and high manufacturing consistency, and can be widely used in engineering projects.

[0007] In order to achieve the above purpose, the embodiment of the present application proposes a new type of planar monopulse sum and difference network based on gap waveguide structure, which has the advantages of simple design, excellent performance, low profile, low cost and high manufacturing consistency, and can be widely used in engineering projects.

[0008] In order to achieve the above purpose, the embodiment of the present application also proposes a monopulse system antenna, which comprises an antenna array surface and a new type of planar monopulse sum and difference network based on gap waveguide structure as described above.

[0009] In order to achieve the above purpose, the embodiment of the present application also proposes a monopulse system radar, which comprises a monopulse system antenna as described above.

[0010] The application provides a novel planar single-pulse and difference network based on a gap waveguide structure, which is mainly used for forming a sum-difference beam of a single-pulse antenna system. The gap waveguide structure is a seven-port cross-shaped sum-difference network, which comprises three sub-sum-difference units, a gap waveguide one-to-two T-shaped power divider and a matching structure. The gap waveguide one-to-two T-shaped power divider is composed of a step matching structure and a pin metal fence. The sub-sum-difference unit is composed of a planar 3dB coupling bridge and a slow wave structure phase shifter. The planar 3dB coupling bridge is composed of a step matching structure, a coupling cavity, upper and lower metal cover plates and a pin metal fence. The slow wave structure phase shifter is composed of a slow wave structure, a step matching structure, upper and lower metal cover plates and a pin metal fence. The slow wave structure phase shifter changes the phase velocity of a channel by introducing a ridge structure with a certain height on one side of the channel, so that the phase difference between the two channels is 90°. The planar 3dB coupling bridge and the slow wave structure phase shifter together form a sub-sum-difference unit of an electromagnetic bandgap structure, which realizes the addition or subtraction of two signals. The three sub-sum-difference units, the gap waveguide one-to-two T-shaped power divider and the matching structure are matched with each other, and the addition or subtraction of four signals is realized. Compared with a traditional sum-difference network using a magic T waveguide structure, the application realizes a welding-free and low-cost design, and only one layer of structure is needed, so that the height (thickness) of the network is effectively reduced, the formation of a sum-difference beam of a single-pulse antenna system is successfully realized, the profile of the scheme is low, the processing is easy, a new design idea is provided for the low-cost and low-profile design of a millimeter wave and above frequency band feed network, and the application can be widely applied in engineering projects.

[0011] Optionally, for the first sub-sum-difference unit 10, electromagnetic waves input through the eighth port P8 or the ninth port P9 are processed by the first planar 3dB coupling bridge 11, and then the energy is divided into two parts, and then the first slow wave structure phase shifter 12 is processed, and then the first port P1 and the second port P2 are reached. If the electromagnetic waves are input from the eighth port P8, the first sub-sum-difference unit 10 forms equal-amplitude opposite-phase signals at the first port P1 and the second port P2. If the electromagnetic waves are input from the ninth port P9, the first sub-sum-difference unit 10 forms equal-amplitude in-phase signals at the first port P1 and the second port P2.

[0012] Optionally, after the electromagnetic wave passes through the gap waveguide one-to-two T-type power divider 40, the matching structure 50, the first sub-hybrid 10 and the second sub-hybrid 20, the energy is divided into the first port P1, the second port P2, the third port P3 and the fourth port P4 output; when the signal is input from the first port P1, the second port P2, the third port P3 and the fourth port P4, the hybrid network forms an azimuth difference signal at the fifth port P5, a sum signal at the sixth port P6, and a pitch difference signal at the seventh port P7; when the third port P3, the fourth port P4, the fifth port P5 and the sixth port P6 are connected to four antenna subarrays respectively, if the signal is input at the sixth port P6, the hybrid network will form a sum beam to obtain the distance information of the target, if the signal is input at the fifth port P5, the hybrid network will form an azimuth difference beam to obtain the angle information of the target in the azimuth plane, and if the signal is input at the seventh port P7, the hybrid network will form a pitch difference beam to obtain the angle information of the target in the pitch plane.

[0013] Optionally, the port isolation of the three sub-hybrids is greater than 24 dB, and the consistency of the transmission amplitude of the four ports (the first port P1, the second port P2, the third port P3 and the fourth port P4) is less than 0.8 dB, and the consistency of the transmission phase is less than 5° in the pre-designed working frequency band.

[0014] Optionally, the slow wave structure of the slow wave structure phase shifter is composed of corrugated structures, the heights of the , , corrugated structures are respectively , , , , the distances between adjacent two corrugated structures are respectively , , .

[0015] Optionally, the slow wave structure of the slow wave structure phase shifter satisfies the phase wavelength relationship as shown below: ; wherein, represents the insertion phase of the channel with the slow wave structure at a length of , represents the insertion phase of the channel without the slow wave structure at a length of , and respectively represent the wavelength of the gap waveguide with the slow wave structure and the wavelength of the gap waveguide without the slow wave structure.

[0016] Optionally, the pin metal fence is composed of a plurality of square metal pins with a height of , a width of , and a period of . The square metal pins have a certain height from the upper metal cover plate, denoted as .

[0017] Optionally, , , satisfy: ; ; ; wherein, represents the wavelength of the gap waveguide with a slow wave structure. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description of the present application will be briefly introduced. Obviously, the following drawings are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings. The drawings described herein are only used to explain the present application, and are not used to limit the present application.

[0019] Figure 1 is a structure diagram of a novel planar single-pulse and difference network based on a gap waveguide structure provided in an embodiment of the present application; Figure 2 is a structure diagram of a sub-difference provided in an embodiment of the present application; Figure 3 is a side view of a sub-difference provided in an embodiment of the present application; Figure 4 is an electric field distribution diagram of a sub-difference provided in an embodiment of the present application; Figure 5 is a diagram of transmission amplitude and transmission phase difference of a sub-difference varying with frequency provided in an embodiment of the present application; Figure 6 is a diagram of voltage standing wave ratio and port isolation of input and output ports of a sub-difference varying with frequency provided in an embodiment of the present application; Figure 7 is a three-dimensional exploded view of a novel planar single-pulse and difference network based on a gap waveguide structure provided in an embodiment of the present application; Figure 8is a schematic diagram of the electric field distribution of the sum-difference network provided in an embodiment of the present application; Figure 9 is a schematic diagram of the transmission amplitude and transmission phase of the sum port of the sum-difference network varying with frequency provided in an embodiment of the present application; Figure 10 is a schematic diagram of the transmission amplitude and transmission phase of the azimuth difference port of the sum-difference network varying with frequency provided in an embodiment of the present application; Figure 11 is a schematic diagram of the transmission amplitude and transmission phase of the elevation difference port of the sum-difference network varying with frequency provided in an embodiment of the present application; Figure 12 is a schematic diagram of the voltage standing wave ratio and port isolation of the input and output ports of the sub-sum-difference network varying with frequency provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. Those skilled in the art can understand that, in the embodiments of the present application, many technical details are proposed in order to make the readers better understand. However, the technical solutions claimed by the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The following embodiments are classified for the convenience of description, and should not constitute any limitation on the specific implementation of the present application, and the following embodiments can be combined and referenced with each other without contradiction.

[0021] An embodiment of the present application proposes a planar novel single-pulse sum-difference network based on a gap waveguide structure. The implementation details of the planar novel single-pulse sum-difference network based on a gap waveguide structure proposed in the embodiment will be described in detail below. The following content only provides related implementation details for the convenience of understanding, and is not necessary for implementing the present solution.

[0022] The specific structure of the planar novel single-pulse sum-difference network based on a gap waveguide structure proposed in the embodiment can be as shown in Figure 1 The structure of the sum-difference network is a cross-shaped seven-port network, which specifically consists of three sub-sum-difference devices (a first sub-sum-difference device 10, a second sub-sum-difference device 20 and a third sub-sum-difference device 30), a gap waveguide one-to-two T-shaped power divider 40 and a matching structure 50. The three sub-sum-difference devices are connected to the gap waveguide one-to-two T-shaped power divider 40 through the matching structure 50.

[0023] The gap waveguide one-to-two T-shaped power divider 40 consists of a stepped matching structure and a pin metal fence.

[0024] The sub-sum and difference unit specifically consists of a planar 3dB coupled bridge and a slow-wave phase shifter. Taking the first sub-sum and difference unit 10 as an example, Figure 2 The specific structure of the first sub-sum and difference unit 10 is shown. The first sub-sum and difference unit 10 consists of a first planar 3dB coupled bridge 11 and a first slow-wave phase shifter 12. The first planar 3dB coupled bridge 11 consists of a stepped matching structure 111, a coupling cavity 112, and upper and lower metal cover plates. Figure 1 , Figure 2 (not shown) and pinned metal fence ( Figure 1 , Figure 2 The first slow-wave phase shifter 12 is composed of a slow-wave structure 121 and a step-matching structure (not shown). Figure 1 , Figure 2 (Not shown), upper and lower metal cover plates ( Figure 1 , Figure 2 (not shown) and pinned metal fence ( Figure 1 , Figure 2 (Not shown) Composition.

[0025] The slow-wave phase shifter changes the phase velocity of the channel by introducing a ridge structure of a certain height on one side, achieving a 90° phase difference between the two channels. Together with a planar 3dB coupled bridge, it forms an electromagnetic bandgap sub-sum and difference device to achieve the addition or subtraction of two signals. The three sub-sum and difference devices, the gap waveguide one-to-two T-type power divider 40, and the matching structure 50 work together to achieve the addition or subtraction of four signals.

[0026] The following is a detailed description of each component of a novel planar single-pulse sum-difference network based on a gap waveguide structure proposed in this embodiment.

[0027] A monopulse radar antenna needs to generate a main beam (sum beam) and two difference beams (azimuth difference and elevation difference) to acquire all the target's position information. The sum beam is used to acquire the target's range information, while the azimuth and elevation difference beams are used to acquire the target's azimuth information (angle information in the azimuth plane) and elevation information (angle information in the elevation plane), respectively. Therefore, a monopulse radar antenna typically consists of antenna subarrays distributed across four quadrants and a monopulse sum and difference network, resulting in a very large design.

[0028] Unlike the traditional corporate and difference network, the embodiment is composed of three sub and difference networks and a gap waveguide one-in-two T-type power divider 40. The gap waveguide one-in-two T-type power divider 40 is composed of a stepped matching structure and a pin metal fence, and also corresponds to the upper and lower metal cover plates. The sub and difference network is composed of a planar 3dB coupling bridge and a slow wave structure phase shifter. The planar 3dB coupling bridge is composed of a stepped matching structure, a coupling cavity, upper and lower metal cover plates and a pin metal fence. The slow wave structure phase shifter is composed of a slow wave structure, a stepped matching structure, upper and lower metal cover plates and a pin metal fence. The side view of the sub and difference network can be shown as Figure 3 It can be clearly seen that the gap structure and the corrugated structure in the sub and difference network. Figure 3

[0029] In the millimeter wave frequency band, the embodiment selects the stop band characteristics of the electromagnetic band gap structure in a specific frequency band to replace the traditional waveguide, and designs a planar 3dB coupling bridge based on the gap waveguide. The designed electromagnetic band gap structure is composed of a pin metal fence and upper and lower metal cover plates. The pin metal fence is specifically composed of a plurality of square metal pins with a height of , a width of , and a period of . The bottom of all square metal pins is connected to the lower metal cover plate and is integrally processed, and the top cover plate of the square metal pin needs to be kept a certain height from the upper metal cover plate, which is denoted as .

[0030] , , need to meet: ; ; ; wherein, represents the wavelength of the gap waveguide with a slow wave structure.

[0031] On the basis of the traditional gap waveguide, the embodiment introduces a corrugated structure, thereby designing a slow wave structure which can achieve a 90° phase shift in a wider frequency band. The planar 3dB coupling bridge and the slow wave structure phase shifter are used to replace the traditional magic T structure to realize a single pulse and difference network. In the case of ensuring consistent electrical performance, the advantages of electromagnetic band gap structure such as layered processing, no welding, large power capacity, high reliability, low loss, etc. can be utilized, which greatly reduces the manufacturing cost and design cycle, and is easy to integrate with the antenna array.

[0032] The slow wave structure of the slow wave structure phase shifter is composed of corrugated structures, is an integer greater than 1.​ The heights of the corrugated structures are respectively , , , The widths of the corrugated structures are respectively , , The intervals between two adjacent corrugated structures are respectively , , .

[0033] The slow wave structure of the slow wave structure phase shifter satisfies the phase wavelength relationship as shown below: ; Wherein, represents the insertion phase of the channel with the slow wave structure at the length of , represents the insertion phase of the channel without the slow wave structure at the length of , and respectively represent the wavelength of the gap waveguide with the slow wave structure and the wavelength of the gap waveguide without the slow wave structure.

[0034] The relevant content of signal transmission and beam forming is introduced below.

[0035] Taking the first hybrid 10 as an example, the electric field distribution when the first hybrid 10 inputs from one of the input ports is as shown in Figure 4 It can be seen that for the first hybrid 10, the electromagnetic wave input through the eighth port P8 or the ninth port P9 is divided into two after the first planar 3dB coupling bridge 11, and then reaches the first port P1 and the second port P2 after the first slow wave structure phase shifter 12 and is output. The transmission amplitude and the transmission phase of the first hybrid 10 can be as shown in Figure 5 .

[0036] If the electromagnetic wave is input from the eighth port P8, the first hybrid 10 forms an equal amplitude anti-phase signal at the first port P1 and the second port P2, and if the electromagnetic wave is input from the ninth port P9, the first hybrid 10 forms an equal amplitude in-phase signal at the first port P1 and the second port P2.

[0037] As shown in Figure 6 , the port isolation of the first hybrid 10 is greater than 24 dB.

[0038] Figure 7 is the three-dimensional exploded view of the entire hybrid network, which clearly shows the cross-shaped seven-port network, Figure 8 is a schematic diagram of the electric field distribution of the entire hybrid network (elevation difference port excitation), from which it can be seen that the electromagnetic wave input through the eighth port P8 or the ninth port P9 is divided into two after the first planar 3dB coupling bridge 11, and then reaches the first port P1 and the second port P2 after the first slow wave structure phase shifter 12 and is output.Figure 8 It can be seen that after the electromagnetic wave is processed by the gap waveguide one-in-two T-type power divider 40, the matching structure 50, the first sum and difference device 10 and the second sum and difference device 20, the energy is evenly divided into the first port P1, the second port P2, the third port P3 and the fourth port P4.

[0039] Figure 9 The transmission amplitude and the transmission phase of the sum port of the sum and difference network are shown, and the transmission amplitude consistency of the first port P1, the second port P2, the third port P3 and the fourth port P4 four output ports is less than 0.8 dB, and the transmission phase consistency is less than 5° in the designed frequency band.

[0040] Figure 10 and Figure 11 The transmission amplitude and the transmission phase of the azimuth difference port and the elevation difference port of the sum and difference network are shown respectively, and it can be seen that when the signal is input from the first port P1, the second port P2, the third port P3 and the fourth port P4, the sum and difference network forms an azimuth difference signal (P1+P2)-(P3+P4) at the fifth port P5, forms a sum signal at the sixth port P6, and forms an elevation difference signal (P1+P3)-(P2+P4) at the seventh port P7.

[0041] When the third port P3, the fourth port P4, the fifth port P5 and the sixth port P6 are respectively connected to four antenna subarrays, if the signal is input at the sixth port P6, the sum and difference network will form a sum beam to obtain the distance information of the target, if the signal is input at the fifth port P5, the sum and difference network will form an azimuth difference beam to obtain the angle information of the target in the azimuth plane, and if the signal is input at the seventh port P7, the sum and difference network will form an elevation difference beam to obtain the angle information of the target in the elevation plane.

[0042] Figure 12 The voltage standing wave ratio and the isolation of the input and output ports of the sum and difference network are shown, and it can be seen from Figure 12 that the voltage standing wave ratio of the input and output ports is less than 1.3, and the port isolation is greater than 23 dB.

[0043] The embodiment provides a planar novel single-pulse sum-difference network based on a gap waveguide structure, which is mainly used for forming a sum-difference beam of a single-pulse system antenna. The gap waveguide structure is a seven-port cross-shaped sum-difference network, which comprises three sub-sum-difference devices, a gap waveguide one-to-two T-shaped power divider and a matching structure. The gap waveguide one-to-two T-shaped power divider is composed of a step matching structure and a pin metal fence. The sub-sum-difference device is composed of a planar 3dB coupling bridge and a slow wave structure phase shifter. The planar 3dB coupling bridge is composed of a step matching structure, a coupling cavity, upper and lower metal cover plates and a pin metal fence. The slow wave structure phase shifter is composed of a slow wave structure, a step matching structure, upper and lower metal cover plates and a pin metal fence. The slow wave structure phase shifter changes the phase velocity of a channel by introducing a ridge structure with a certain height on one side of the channel, so that the phase difference between the two channels is 90°. The planar 3dB coupling bridge and the slow wave structure phase shifter together form a sub-sum-difference device of an electromagnetic bandgap structure, so as to realize the addition or subtraction of two signals. The three sub-sum-difference devices, the gap waveguide one-to-two T-shaped power divider and the matching structure are matched with each other, so as to realize the addition or subtraction of four signals. Compared with a traditional sum-difference network adopting a magic T waveguide structure, the embodiment successfully realizes a welding-free and low-cost design, and only needs one layer of structure, so that the height (thickness) of the network is effectively reduced, the sum-difference beam of the single-pulse system antenna is successfully formed, the profile of the embodiment is low and easy to process, a new design idea is provided for low-cost and low-profile design of a feed network in a millimeter wave and above frequency band, and the embodiment can be widely applied in engineering projects.

[0044] It is worth mentioning that each module and module involved in the embodiment is a logical module. In actual application, one logical unit can be one physical unit, a part of one physical unit or a combination of multiple physical units. In addition, in order to highlight the innovative part of the application, units not closely related to solving the technical problems proposed in the application are not introduced in the embodiment, but this does not mean that other units do not exist in the embodiment.

[0045] Another embodiment of the application provides a single-pulse system antenna, which comprises an antenna array surface and a planar novel single-pulse sum-difference network based on a gap waveguide structure as described in the sum-difference network embodiment.

[0046] Another embodiment of the application provides a single-pulse system radar, which comprises a single-pulse system antenna as described in the single-pulse system antenna embodiment.

[0047] Those skilled in the art can understand that the above-mentioned embodiments are specific embodiments for realizing the present application, and various changes can be made in form and details in practical application without departing from the spirit and scope of the present application. For those skilled in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements are also regarded as the protection scope of the present application.

Claims

1. A planar novel single-pulse and difference network based on gap waveguide structure, characterized by, The structure of the sum-difference network is a cross-shaped seven-port network, which specifically comprises three sub-sum-difference devices, a gap waveguide one-to-two T-type power divider (40) and a matching structure (50), the three sub-sum-difference devices are connected with the gap waveguide one-to-two T-type power divider (40) through the matching structure (50), and the three sub-sum-difference devices are respectively a first sub-sum-difference device (10), a second sub-sum-difference device (20) and a third sub-sum-difference device (30); The gap waveguide one-to-two T-type power divider (40) is composed of a stepped matching structure and a pin metal fence; The sub-sum-difference device is composed of a planar 3dB coupling bridge and a slow wave structure phase shifter, the planar 3dB coupling bridge is composed of a stepped matching structure, a coupling cavity, upper and lower metal cover plates and a pin metal fence, and the slow wave structure phase shifter is composed of a slow wave structure, a stepped matching structure, upper and lower metal cover plates and a pin metal fence; The slow wave structure phase shifter changes the phase velocity of the channel by introducing a certain height of ridge structure on one side channel, so as to realize that the phases of two channels are 90° different, and the planar 3dB coupling bridge and the slow wave structure phase shifter together form a sub-sum-difference device of an electromagnetic band gap structure, so as to realize the addition or subtraction of two signals, and the three sub-sum-difference devices, the gap waveguide one-to-two T-type power divider and the matching structure are matched with each other to realize the addition or subtraction of four signals.

2. The sum-and-difference network of claim 1, wherein, The three sub-sum-difference devices are completely the same in structure, for the first sub-sum-difference device (10), electromagnetic waves input through the eighth port (P8) or the ninth port (P9) are processed by the first planar 3dB coupling bridge (11), and then the energy is divided into two parts, and then the energy is processed by the first slow wave structure phase shifter (12) and reaches the first port (P1) and the second port (P2); If the electromagnetic waves are input from the eighth port (P8), the first sub-sum-difference device (10) forms equal-amplitude opposite-phase signals at the first port (P1) and the second port (P2); If the electromagnetic waves are input from the ninth port (P9), the first sub-sum-difference device (10) forms equal-amplitude in-phase signals at the first port (P1) and the second port (P2).

3. The sum-and-difference network of claim 2, wherein, After the electromagnetic waves pass through the gap waveguide one-to-two T-type power divider (40), the first sub-sum-difference device (10) and the second sub-sum-difference device (20), the energy is divided into the first port (P1), the second port (P2), the third port (P3) and the fourth port (P4); When signals are input from the first port (P1), the second port (P2), the third port (P3) and the fourth port (P4), the sum-difference network forms a bearing difference signal at the fifth port (P5), a sum signal at the sixth port (P6) and a pitch difference signal at the seventh port (P7); When the third port (P3), the fourth port (P4), the fifth port (P5) and the sixth port (P6) are connected with four antenna sub-arrays respectively, if signals are input at the sixth port (P6), the sum-difference network forms a sum beam to obtain distance information of a target, if signals are input at the fifth port (P5), the sum-difference network forms a bearing difference beam to obtain angle information of the target in a bearing plane, and if signals are input at the seventh port (P7), the sum-difference network forms a pitch difference beam to obtain angle information of the target in a pitch plane.

4. The sum-and-difference network of claim 3, wherein, The port isolation of the three sub-sum and difference devices is greater than 24 dB, and the consistency of the transmission amplitude of the first port (P1), the second port (P2), the third port (P3) and the fourth port (P4) is less than 0.8 dB, and the consistency of the transmission phase is less than 5° in the pre-designed working frequency band.

5. The sum-and-difference network of claim 1, wherein, The slow wave structure of the slow wave structure phase shifter is composed of corrugated structures, the heights of the corrugated structures are respectively , , , the widths of the corrugated structures are respectively , , , and the intervals between two adjacent corrugated structures are respectively , , .

6. The sum-and-difference network of claim 5, wherein, The slow wave structure of the slow wave structure phase shifter satisfies a phase wavelength relationship as shown below: ； wherein denotes the insertion phase of the channel with slow wave structure at a length of denotes the insertion phase of the channel without slow wave structure at a length of denotes the insertion phase of the channel without slow wave structure at a length of denotes the insertion phase of the channel without slow wave structure at a length of and denote the wavelength of the gap waveguide with slow wave structure and the wavelength of the gap waveguide without slow wave structure, respectively.

7. The sum-and-difference network of claim 1, wherein, The pin metal fence is composed of a plurality of square metal pins with a height of , a width of , and a period of . The square metal pins have a certain height from the upper metal cover plate, denoted as .

8. The sum-and-difference network of claim 7, wherein, , , satisfies: ； ； ； wherein denotes the wavelength of the gap waveguide with slow wave structure.

9. A single-pulse system antenna, characterized by Comprising: An antenna array surface and a novel planar single pulse and difference network based on a gap waveguide structure according to any one of claims 1 to 8.

10. A monopulse regime radar, characterized by Comprising: A single pulse system antenna according to claim 9.

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