High-dispersion dual-band high-scanning-rate scanning leaky-wave antenna

Abstract

The invention discloses a high-dispersion dual-band high-scanning-rate scanning leaky-wave antenna which comprises a dielectric substrate, an upper conductor layer and a lower conductor layer. The upper conductor layer is integrated with an H-shaped high-dispersion electromagnetic structure transmission line and a thin oval unit, the right end of the H-shaped high-dispersion electromagnetic structure transmission line is connected with an upper conductor layer matching network and a plane feeder line structure, and the left end of the H-shaped high-dispersion electromagnetic structure transmission line is connected with an upper conductor layer H-shaped impedance transition section. The right end of the slotted high-dispersion electromagnetic structure transmission line is connected with the lower conductor layer matching network, the trapezoidal impedance matching ground and the metal grounding layer, and the left end of the slotted high-dispersion electromagnetic structure transmission line is connected with the lower conductor layer slot-shaped impedance transition section; the H-shaped high-dispersion electromagnetic structure transmission line and the slotted high-dispersion electromagnetic structure transmission line are coupled through the dielectric substrate to form a double-layer high-dispersion electromagnetic structure transmission line; the antenna has the advantages of dual-band independent control, high radiation efficiency and high scanning rate, and meanwhile, the communication capacity, the real-time sensing performance and the anti-interference performance are improved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a high-dispersion dual-band high-scan rate scanning leaky-wave antenna. Background Art

[0002] High-dispersion electromagnetic structures can excite surface waves on periodic metal surfaces, exhibiting deep subwavelength characteristics, localized field enhancement, and nonlinear dispersion curves. New electromagnetic devices designed using this structure offer advantages such as compactness, light weight, and low cost, and have broad application prospects in highly integrated wireless communication systems.

[0003] Double-layer high-dispersion electromagnetic structures have become a core solution for miniaturized high-frequency device design due to their enhanced field confinement, lower cutoff frequency, and increased freedom in dispersion control. This structure enhances slow-wave characteristics and energy concentration through electromagnetic coupling between upper and lower metal elements, providing a new approach for multi-band antenna design.

[0004] Currently, scanning leaky-wave antennas primarily operate in a single-band mode, failing to meet the urgent demands of modern communication systems for multi-band / multi-function collaborative operation, efficient spectrum resource utilization, and multi-scenario compatibility. Dual-band leaky-wave antennas, which achieve beam scanning in two independent frequency bands through a single structure, significantly reduce hardware complexity, optimize spatial layout, and improve spectrum utilization and system flexibility. These antennas have become a key development direction in antenna design.

[0005] Currently, there are three main design methods for dual-band scanning leaky-wave antennas: multi-structure splicing design, multi-mode fusion design, and spatial harmonic control design. Multi-structure splicing design achieves dual-band operation by cascading special-shaped transmission line structures. Through parameter optimization, the working frequency bands of each structure are made non-overlapping, thereby achieving multi-band operation. However, there are problems such as low structural reuse rate and excessive physical size. Multi-mode fusion design uses multiple modes to achieve control of multiple frequency bands. There are problems such as complex feeding network and increased processing difficulty. Spatial harmonic control uses -1st and -2nd spatial harmonics to separate radiation. Although it can simplify the structure, it is limited by the limited scanning angle and low scanning rate.

[0006] The above problems should be considered and solved during the design and production of high-dispersion dual-band high-scan rate leaky-wave antennas. Summary of the Invention

[0007] The purpose of the present invention is to provide a dual-band leaky-wave antenna that realizes independent operation of the -1st harmonic and the -2nd harmonic through a double-layer high-dispersion electromagnetic structure, uses a simple and compact structure to achieve full-space scanning of the low-frequency band, large-angle scanning of the high-frequency band, and ultra-high scanning rate, thereby solving the problems of low structural reuse rate, high structural complexity, limited scanning angle and low scanning rate in the prior art.

[0008] To achieve the above object, the present invention provides the following technical solution: a high-dispersion dual-band high-scan rate scanning leaky-wave antenna, comprising a dielectric substrate, wherein the upper and lower surfaces of the dielectric substrate respectively comprise an upper conductor layer and a lower conductor layer;

[0009] The upper conductor layer includes an H-shaped high-dispersion electromagnetic structure transmission line and a plurality of thin elliptical units periodically arranged on both sides thereof. The right end of the H-shaped high-dispersion electromagnetic structure transmission line is connected to the upper conductor layer matching network and the planar feed line in sequence, and the left end is connected to the H-shaped impedance gradient section of the upper conductor layer. The end of the planar feed line is the feeding port of the antenna and is connected to the metal ground layer by using an SMA connector.

[0010] The lower conductor layer includes a slotted high-dispersion electromagnetic structure transmission line, the right end of the slotted high-dispersion electromagnetic structure transmission line is connected to the lower conductor layer matching network, the ladder impedance matching ground and the metal grounding layer in sequence, and the left end is connected to the slotted impedance gradient section of the lower conductor layer; wherein, the H-shaped high-dispersion electromagnetic structure transmission line and the slotted high-dispersion electromagnetic structure transmission line form electromagnetic coupling through the dielectric substrate, together forming a double-layer high-dispersion electromagnetic structure transmission line, and the upper conductor layer matching network and the lower conductor layer matching network correspond to each other in space to form a double-layer gradient matching network.

[0011] Preferably, the H-shaped high-dispersion electromagnetic structure transmission line is composed of periodically repeated H-shaped high-dispersion electromagnetic structure units, and the slotted high-dispersion electromagnetic structure transmission line is composed of periodically repeated slotted high-dispersion electromagnetic structure units.

[0012] Preferably, the upper conductor layer matching network is composed of a plurality of H-shaped matching units with decreasing sizes arranged in sequence, wherein the height of the largest H-shaped matching unit is smaller than the height of the H-shaped high-dispersion electromagnetic structure unit.

[0013] Preferably, the lower conductor layer matching network is composed of a plurality of slotted matching units with decreasing sizes arranged in sequence, wherein the height of the largest slotted matching unit is smaller than the height of the slotted high-dispersion electromagnetic structure unit.

[0014] Preferably, the trapezoidal impedance matching ground adopts a trapezoidal profile design to provide a gradual impedance transition between the metal ground layer and the lower conductor layer matching network.

[0015] Preferably, by changing the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit, the slope of the dispersion curve and the cutoff frequency corresponding to the double-layer high-dispersion electromagnetic structure unit are regulated, and then the working frequency band and the corresponding bandwidth of the antenna are adjusted. When the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit increase, the working frequency of the antenna decreases and the working bandwidth becomes wider; when the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit decrease, the working frequency of the antenna increases and the working bandwidth becomes narrower; the dispersion curve corresponding to the double-layer high-dispersion electromagnetic structure wave unit has a lower cutoff frequency and a steeper gradient change than the dispersion curve corresponding to the single-layer high-dispersion electromagnetic structure unit, which has significant advantages in the realization of a dual-band leaky wave antenna.

[0016] Preferably, the effective electrical length of the double-layer high-dispersion electromagnetic structure radiation structure is changed by increasing or decreasing the number of double-layer high-dispersion electromagnetic structure units and the number of fine elliptical units, thereby regulating the radiation effect of the antenna; when the number of double-layer high-dispersion electromagnetic structure units and the number of fine elliptical units increase, the effective electrical length of the double-layer high-dispersion electromagnetic structure radiation structure increases relatively, so that the electromagnetic waves transmitted on the high-dispersion electromagnetic structure strips are further radiated into the free space, thereby improving the radiation effect of the antenna; conversely, when the number of double-layer high-dispersion electromagnetic structure units and the number of fine elliptical units decreases, the effective electrical length of the double-layer high-dispersion electromagnetic structure radiation structure decreases, and the radiation effect of the antenna is relatively weakened.

[0017] Preferably, by adjusting the spacing between the fine elliptical units, the operating frequency bands of the -1st and -2nd order spatial harmonics excited by the double-layer high-dispersion electromagnetic structure in the fast wave region are directly controlled. When the spacing between adjacent fine elliptical units increases, the operating frequency of the antenna decreases and the operating bandwidth becomes wider; when the spacing between the fine elliptical units decreases, the operating frequency of the antenna increases and the operating bandwidth becomes narrower.

[0018] Preferably, the spacing distance of the thin elliptical units satisfies the following harmonic isolation condition: the frequency corresponding to the -1-order spatial harmonic in the end-fire direction is higher than the frequency corresponding to the -2-order spatial harmonic in the back-fire direction, and the frequency corresponding to the -2-order spatial harmonic in the end-fire direction is higher than the frequency corresponding to the -3-order spatial harmonic in the back-fire direction. This harmonic isolation condition ensures that the -1-order spatial harmonic and the -2-order spatial harmonic can operate stably in independent frequency bands, avoiding overlap and interference with the radiation frequency bands of other spatial harmonics, thereby realizing the dual-band independent scanning function.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. In the present invention, the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure can realize continuous scanning of the main beam from rear backfire to forward endfire in the low-frequency band of 2.3-3.5 GHz, with full-space scanning capability and an absolute scanning rate of up to 150° / %. In the high-frequency band of 4.2-4.95 GHz, it can realize continuous scanning from rear backfire to 40° forward, with an absolute scanning rate of up to 173° / %. It has the advantages of independent dual-band control, narrow occupied bandwidth, stable gain, high radiation efficiency, high scanning rate, and small size. It provides efficient beamforming and multi-band coverage capabilities for 5G communication systems, vehicle-mounted radars, and satellite terminals, while significantly improving communication capacity, real-time perception, and anti-interference performance in complex scenarios.

[0021] 2. In the present invention, the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure excites multiple spatial harmonics for radiation by asymmetrically disposing a number of periodically arranged thin elliptical units on the upper and lower sides of the H-shaped high-dispersion electromagnetic structure transmission line. The electromagnetic coupling of the double-layer metal units significantly enhances the slow-wave characteristics, thereby allowing the -1st harmonic and -2nd harmonic to operate in different frequency bands without interfering with each other. This design breaks through the limitations of traditional single-band leaky-wave antennas and provides a new approach to multi-band antenna design. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0023] In the attached figure:

[0024] Figure 1 3D schematic diagram of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0025] Figure 2 Schematic diagram of the upper conductor layer and the lower conductor layer of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0026] Figure 3 This is a dispersion curve diagram comparing single-layer H-shaped and double-layer H+ slotted high-dispersion electromagnetic structural units of the present invention;

[0027] Figure 4 is the Brillouin diagram of multiple spatial harmonic modes in different modes;

[0028] Figure 5 Schematic diagram of the simulated and measured S parameters of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0029] Figure 6Schematic diagram of the simulated directional pattern and the measured directional pattern in the low frequency band of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0030] Figure 7 Schematic diagram of the simulated directional pattern and the measured directional pattern in the high frequency band of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0031] Figure 8 Schematic diagram of the simulated and measured gain and radiation efficiency of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure according to an embodiment of the present invention;

[0032] Numbers in the figure: 1. Dielectric substrate; 2. Upper conductor layer; 21. H-shaped high-dispersion electromagnetic structure transmission line; 22. Thin elliptical unit; 23. H-shaped impedance gradient section of upper conductor layer; 24. Matching network of upper conductor layer; 25. Second planar feed line; 26. First planar feed line; 3. Lower conductor layer; 31. Slotted high-dispersion electromagnetic structure transmission line; 33. Slotted impedance gradient section of lower conductor layer; 34. Matching network of lower conductor layer; 35. Trapezoidal impedance matching ground; 36. Metal ground layer. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0034] Example: Figure 1 and Figure 2 As shown, a high-dispersion dual-band, high-scan-rate scanning leaky-wave antenna comprises a dielectric substrate 1, with an upper conductor layer 2 and a lower conductor layer 3 formed on the upper and lower surfaces of the dielectric substrate 1, respectively. Both the upper and lower conductor layers 2 and 3 are metal conductor layers etched closely to the upper and lower surfaces of the dielectric substrate 1. The upper and lower conductor layers 2 and 3 are fabricated using copper cladding technology on both sides of the dielectric substrate 1.

[0035] like Figure 2As shown, the upper conductor layer 2 includes: an H-shaped high-dispersion electromagnetic structure transmission line 21, thin elliptical units 22, an upper conductor layer H-shaped impedance gradient section 23, an upper conductor layer matching network 24, a first planar feed line 26, and a second planar feed line 25. The H-shaped high-dispersion electromagnetic structure transmission line 21 is located in the middle, and its two ends are respectively connected by the upper conductor layer matching network 24 and the upper conductor layer H-shaped impedance gradient section 23. The planar feed line structure consists of a first planar feed line 26 and a second planar feed line 25. The right end of the first planar feed line 26 is the antenna feeding port and is connected to the metal ground layer through a microwave high-frequency connector. A plurality of periodically arranged thin elliptical units 22 are respectively provided on the upper and lower sides of the H-shaped high-dispersion electromagnetic structure transmission line 21. The lower conductor layer 3 includes: a slotted high-dispersion electromagnetic structure transmission line 31, a lower conductor layer slotted impedance gradient section 33, a lower conductor layer matching network 34, a ladder-shaped impedance matching ground 35 and a metal grounding layer 36, wherein the slotted high-dispersion electromagnetic structure transmission line 31 is located in the middle, the right end of the slotted high-dispersion electromagnetic structure transmission line 31 is connected to the lower conductor layer matching network 34, the ladder-shaped impedance matching ground 35 and the metal grounding layer 36, and the left end is connected to the lower conductor layer slotted impedance gradient section 33; the H-shaped high-dispersion electromagnetic structure transmission line 21 and the slotted high-dispersion electromagnetic structure transmission line 31 form a double-layer high-dispersion electromagnetic structure transmission line.

[0036] The upper conductor layer matching network 24 is composed of eight H-shaped high-dispersion electromagnetic structural units of varying heights connected in series in a trapezoidal pattern. Starting from the second planar feed line 25, the height gradient of the H-shaped high-dispersion electromagnetic structural units increases until it forms a gradient with the height of the units in the H-shaped high-dispersion electromagnetic structure transmission line 21. The lower conductor layer matching network 34 is composed of eight slotted high-dispersion electromagnetic structural units of varying heights connected in series in a trapezoidal pattern. Starting from the trapezoidal impedance matching ground 35, the height gradient of the slotted high-dispersion electromagnetic structural units increases until it forms a gradient with the height of the units in the slotted high-dispersion electromagnetic structure transmission line 31. The upper conductor layer matching network 24 and the lower conductor layer matching network 34 correspond to each other vertically, forming a double-layer gradient matching network. The second planar feed line 25 provides gradient impedance matching between the first planar feed line 26 and the upper conductor layer matching network 24. The trapezoidal impedance matching ground 35 provides gradient impedance matching between the metal ground layer 36 and the lower conductor layer matching network 34.

[0037] The metal feeding structure includes a first planar feeding line 26 , a second planar feeding line 25 , a ladder impedance matching ground 35 and a metal grounding layer 36 , and the double-layer tapered matching network includes an upper conductor layer matching network 24 and a lower conductor layer matching network 34 .

[0038] This dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure can regulate the slope of the dispersion curve and the cutoff frequency corresponding to the double-layer high-dispersion electromagnetic structure unit by changing the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit, thereby adjusting the antenna's operating frequency band and corresponding bandwidth: when the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit increase, the antenna's operating frequency decreases and the operating bandwidth becomes wider; when the height of the H-shaped high-dispersion electromagnetic structure unit and the groove depth of the slot-shaped high-dispersion electromagnetic structure unit decrease, the antenna's operating frequency increases and the operating bandwidth becomes narrower.

[0039] This dual-band high-scanning-rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure achieves regulation of the length of the dual-band high-scanning-rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure by adjusting the number of units of the H-shaped high-dispersion electromagnetic structure transmission line 21 and the slotted high-dispersion electromagnetic structure transmission line 31, as well as the number of fine elliptical units 22, thereby achieving regulation of the antenna gain: when the number of units and the fine elliptical units 22 increase, the length of the dual-band high-scanning-rate leaky-wave antenna based on the double-layer high-dispersion electromagnetic structure increases, thereby allowing the electromagnetic waves transmitted on the H-shaped high-dispersion electromagnetic structure transmission line 21 and the slotted high-dispersion electromagnetic structure transmission line 31 to be further radiated into the free space, thereby achieving improved radiation effect; conversely, when the number of units and the fine elliptical units 22 decrease, the length of the dual-band high-scanning-rate leaky-wave antenna based on the double-layer high-dispersion electromagnetic structure decreases, and the radiation effect is weakened.

[0040] This dual-band, high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure excites multiple spatial harmonics in the double-layer high-dispersion electromagnetic structure by asymmetrically loading fine elliptical units 22 on both sides of the H-shaped high-dispersion electromagnetic structure transmission line 21. This allows for the radiation effect to be achieved when the spatial harmonics enter the fast-wave region. By adjusting the spacing between the fine elliptical units 22, the operating frequency bands of the -1st and -2nd order spatial harmonics excited by the double-layer high-dispersion electromagnetic structure in the fast-wave region are directly controlled. When the spacing between adjacent fine elliptical units 22 increases, the antenna's operating frequency decreases and its operating bandwidth widens; when the spacing between the fine elliptical units 22 decreases, the antenna's operating frequency increases and its operating bandwidth narrows. The spacing between the fine elliptical units 22 is designed to ensure that the frequency corresponding to the -1st order spatial harmonic in the endfire direction is higher than the frequency corresponding to the -2nd order spatial harmonic in the backfire direction, and that the frequency corresponding to the -2nd order spatial harmonic in the endfire direction is higher than the frequency corresponding to the -3rd order spatial harmonic in the backfire direction, thereby meeting the operating conditions of the dual-band leaky-wave antenna.

[0041] like Figure 3As shown, this dual-band, high-scan-rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure modulates the slope of the dispersion curve and cutoff frequency of the double-layer high-dispersion electromagnetic structure by adjusting the height h of the H-shaped high-dispersion electromagnetic structure unit and the slot depth w of the slot-shaped high-dispersion electromagnetic structure unit, thereby regulating the antenna's operating frequency and bandwidth. Specifically, when the height h of the H-shaped high-dispersion electromagnetic structure unit and the slot depth w of the slot-shaped high-dispersion electromagnetic structure unit increase, the antenna's operating frequency decreases and its operating bandwidth narrows. When the height h of the H-shaped high-dispersion electromagnetic structure unit and the slot depth w of the slot-shaped high-dispersion electromagnetic structure unit decrease, the antenna's operating frequency increases and its operating bandwidth widens.

[0042] like Figure 3 As shown, the dispersion curves of both the single-layer H-shaped high-dispersion electromagnetic structure unit and the double-layer H+ slotted high-dispersion electromagnetic structure unit deviate from the dispersion curve of light, indicating that their wave vectors are large and exhibit slow-wave characteristics. When the height h of the H-shaped high-dispersion electromagnetic structure unit is the same, the double-layer H+ slotted high-dispersion electromagnetic structure unit exhibits a lower cutoff frequency than the single-layer H-shaped high-dispersion electromagnetic structure unit. This means that the double-layer H+ slotted high-dispersion electromagnetic structure unit has a stronger ability to control dispersion. In the same frequency range as the single-layer H-shaped high-dispersion electromagnetic structure unit, it can provide a larger phase variation for the frequency scanning antenna, with the potential for a large scanning angle and high scanning rate.

[0043] Figure 4 The Brillouin diagrams of various spatial harmonics in different modes after loading the thin elliptical unit 22 are shown. In the design of leaky-wave antennas, mode I is often used as the dominant radiation mode. Specifically, its n=-1 represents the -1st-order spatial harmonic, radiating into the fast-wave region at 2.5-3.6 GHz, and n=-2 represents the -2nd-order spatial harmonic, radiating into the fast-wave region at 4.2-5.2 GHz. The two operating frequency bands are completely separated without overlap, ensuring independent dual-band scanning characteristics. Simultaneously, the spatial harmonic radiation of mode II is in a non-radiating state in these two frequency bands, effectively avoiding interference from multimode coupling and harmonic interference, thereby ensuring that the main radiation modes (the -1st and -2nd-order harmonics of mode I) achieve optimal radiation effects within their respective operating frequency bands.

[0044] The simulation and actual measurement results of the embodiment are as follows:

[0045] Figure 5 This is the S-parameter diagram of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure. Figure 5The antenna's measured operating frequency band in the low-band is 2.3-3.5 GHz, with an absolute occupied bandwidth of 1.2 GHz. Its measured operating frequency band in the high-band is 4.2-4.95 GHz, with an absolute occupied bandwidth of 0.75 GHz, demonstrating its low bandwidth. Within these two operating frequency bands, the reflection coefficient S11 remains essentially below -10 dB, demonstrating excellent antenna performance. While the measured and simulated results exhibit a frequency offset of approximately 0.1 GHz, the overall trend remains consistent.

[0046] Figure 6 Schematic diagram of the simulated radiation patterns at low frequencies of 2.5 GHz, 2.7 GHz, 2.9 GHz, 3.1 GHz, 3.3 GHz, 3.5 GHz, and 3.6 GHz and the measured radiation patterns at 2.3 GHz, 2.6 GHz, 2.8 GHz, 3.0 GHz, 3.2 GHz, 3.4 GHz, and 3.5 GHz of the dual-band high-scan rate leaky-wave antenna having a double-layer high-dispersion electromagnetic structure in an embodiment; Figure 6 It can be seen that in the low-frequency band, the main beam can be continuously scanned from rear backfire to forward endfire, has the ability of full-space beam scanning, and has an ultra-high scanning rate of 150° / GHz.

[0047] Figure 7 The figure shows the simulated radiation patterns of the dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure in the high-frequency bands of 4.2GHz, 4.4GHz, 4.6GHz, 4.8GHz, 5.0GHz and 5.1GHz and the measured radiation patterns at 4.2GHz, 4.3GHz, 4.5GHz, 4.7GHz, 4.9GHz and 4.95GHz. Figure 7 It can be seen that in the high frequency band, the main beam can continuously scan from rearward backscatter to 40 degrees forward, has a large-angle beam scanning capability, and has an ultra-high scanning rate of 173° / GHz.

[0048] Figure 8 This is a schematic diagram of the simulated and measured gain and radiation efficiency of a dual-band high-scan rate leaky-wave antenna with a double-layer high-dispersion electromagnetic structure in two frequency bands. The antenna has a maximum gain of 10.5 dBi and an average radiation efficiency of more than 80%, achieving a dual-band leaky-wave antenna with relatively high gain and radiation efficiency.

[0049] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A high-dispersion dual-band high-scan rate scanning leaky-wave antenna, characterized by: The dielectric substrate comprises a dielectric substrate, wherein the upper and lower surfaces of the dielectric substrate respectively comprise an upper conductor layer and a lower conductor layer; The upper conductor layer includes an H-shaped high-dispersion electromagnetic structure transmission line and a plurality of thin elliptical units periodically arranged on both sides thereof. The right end of the H-shaped high-dispersion electromagnetic structure transmission line is connected to the upper conductor layer matching network and the planar feed line in sequence, and the left end is connected to the H-shaped impedance gradient section of the upper conductor layer. The end of the planar feed line is the feeding port of the antenna and is connected to the metal ground layer by using an SMA connector. The lower conductor layer includes a slotted high-dispersion electromagnetic structure transmission line, the right end of the slotted high-dispersion electromagnetic structure transmission line is connected to the lower conductor layer matching network, the ladder impedance matching ground and the metal grounding layer in sequence, and the left end is connected to the slotted impedance gradient section of the lower conductor layer; wherein, the H-shaped high-dispersion electromagnetic structure transmission line and the slotted high-dispersion electromagnetic structure transmission line form electromagnetic coupling through the dielectric substrate, together forming a double-layer high-dispersion electromagnetic structure transmission line, and the upper conductor layer matching network and the lower conductor layer matching network correspond to each other in space to form a double-layer gradient matching network.

2. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: The H-shaped high-dispersion electromagnetic structure transmission line is composed of periodically repeated H-shaped high-dispersion electromagnetic structure units, and the slotted high-dispersion electromagnetic structure transmission line is composed of periodically repeated slotted high-dispersion electromagnetic structure units.

3. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 2, characterized in that: The upper conductor layer matching network is composed of a plurality of H-shaped matching units with decreasing sizes arranged in sequence, wherein the height of the largest H-shaped matching unit is smaller than the height of the H-shaped high-dispersion electromagnetic structure unit.

4. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 2, characterized in that: The lower conductor layer matching network is composed of a plurality of slotted matching units with decreasing sizes arranged in sequence, wherein the height of the largest slotted matching unit is smaller than the height of the slotted high-dispersion electromagnetic structure unit.

5. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: The trapezoidal impedance matching ground is designed with a trapezoidal profile to provide a gradual impedance transition between the metal ground layer and the lower conductor layer matching network.

6. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: By changing the height of the H-shaped high-dispersion electromagnetic structure unit and the slot depth of the slot-shaped high-dispersion electromagnetic structure unit, the slope of the dispersion curve and the cutoff frequency corresponding to the double-layer high-dispersion electromagnetic structure unit are controlled, thereby adjusting the operating frequency band and corresponding bandwidth of the antenna.

7. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: By increasing or decreasing the number of double-layer high-dispersion electromagnetic structure units and the number of thin elliptical units, the effective electrical length of the double-layer high-dispersion electromagnetic structure radiation structure is changed, thereby adjusting the radiation effect of the antenna.

8. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: By adjusting the spacing between the thin elliptical units, the operating frequency bands of the -1st and -2nd order spatial harmonics excited by the double-layer high-dispersion electromagnetic structure in the fast wave region can be directly controlled. When the spacing increases, the operating frequency decreases and the bandwidth widens, and when the spacing decreases, the operating frequency increases and the bandwidth narrows.

9. The high-dispersion dual-band high-scan rate scanning leaky-wave antenna according to claim 1, characterized in that: The spacing distance of the thin elliptical units is set to meet the following harmonic isolation conditions: the frequency corresponding to the -1 order spatial harmonic in the end-fire direction is higher than the frequency corresponding to the -2 order spatial harmonic in the back-fire direction, and the frequency corresponding to the -2 order spatial harmonic in the end-fire direction is higher than the frequency corresponding to the -3 order spatial harmonic in the back-fire direction.

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