Arbitrary dielectric constant end-on-fire leaky-wave antenna based on subarray alternation

Abstract

The invention discloses an arbitrary dielectric constant end-on-fire leaky-wave antenna based on subarray alternation. The antenna comprises an upper metal layer, a dielectric substrate and a lower metal layer which are sequentially arranged from top to bottom, the upper-layer metal comprises a first metal wire and first sub-arrays which are alternately arranged on the two sides of the first metal wire; the lower-layer metal comprises a second metal wire and second sub-arrays which are alternately arranged on the two sides of the second metal wire; the first sub-array and the second sub-array are symmetrical relative to the axis I of the first metal wire and the second metal wire; the first sub-array and the second sub-array comprise one or more radiation units with the same number. According to the antenna, a stable end-fire directional diagram is generated through spatio-1 harmonic radiation, an end-fire leaky-wave antenna can be realized on a dielectric substrate with a lower dielectric constant, the processing difficulty is reduced, and meanwhile, a higher gain length ratio and a larger gain bandwidth are realized.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic waves and antennas, and in particular to an end-fire leaky wave antenna with arbitrary dielectric constant based on alternating subarrays. Background Art

[0002] End-fire leaky-wave antennas have the advantages of high gain, low profile, and simple structure, and are widely used in fields such as radiometers and automotive radar systems. However, the current design of end-fire leaky-wave antennas has the problems of low gain-to-length ratio and difficult processing. Traditional end-fire leaky-wave antennas use a joint design of feeder and unit. The radiation performance of the array is affected by the feeder and unit. The radiation aperture of the antenna array is unevenly distributed, making it difficult to achieve a high gain-to-length ratio. In addition, traditional end-fire leaky-wave antennas are designed based on air dielectrics or high dielectric constant substrates, which are complex to assemble and difficult to process. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects in the existing technologies and provide an end-fire leaky wave antenna with arbitrary dielectric constant based on alternating subarrays. The present invention can reduce the requirements of the end-fire leaky wave antenna on the dielectric constant of the substrate, making it easier to process and improving the gain-to-length ratio of the antenna.

[0004] To achieve the above object, the present invention adopts the following technical solution:

[0005] An end-fire leaky wave antenna with arbitrary dielectric constant based on alternating subarrays, comprising an upper metal layer, a dielectric substrate and a lower metal layer arranged in sequence from top to bottom; the upper metal layer comprises a first metal wire and a first subarray arranged alternately on both sides of the first metal wire; the lower metal layer comprises a second metal wire and a second subarray arranged alternately on both sides of the second metal wire; the first subarray and the second subarray are symmetrical with respect to the axis of the first metal wire or the second metal wire; and a subarray of the first subarray and the second subarray comprises the same number of one or more radiation units.

[0006] Optionally, when each of the first subarray and the second subarray includes one radiation unit, the dielectric constant of the dielectric substrate is greater than 4 and less than 9.

[0007] Optionally, when one of the first sub-array and the second sub-array includes a plurality of radiation units, the dielectric constant of the dielectric substrate ranges from 1 to 4.

[0008] Preferably, the end-fire leaky wave antenna utilizes space-1st harmonic radiation, and the propagation constant satisfies For the -1st harmonic, the propagation constant satisfies β -1 =k0; where β is the propagation constant, d is the subarray spacing between the first subarray and the second subarray, ε ris the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0009] Preferably, the subarray spacing of the first subarray and the second subarray is the same and satisfies the subarray spacing Where d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0010] Preferably, when a subarray includes a plurality of the radiation units, the spacing between the radiation units in the subarray is the same, and the spacing between the radiation units satisfies d ele =d / N; where d is the subarray spacing, and N (N≥1) is the number of radiation units in the subarray.

[0011] Preferably, the radiation unit operates in a non-resonant state.

[0012] Preferably, the radiation unit couples energy from the upper metal wire, the lower metal wire and the space simultaneously.

[0013] Preferably, the radiation unit has no influence on the matching performance of the transmission line formed by the upper metal wire and the lower metal wire.

[0014] Preferably, the subarray radiation patterns of the first subarray and the second subarray can suppress the side lobes generated by the array factor, so that the antenna array radiates a stable end-fire radiation pattern.

[0015] It can be seen from the above technical solution that, compared with the prior art, the present invention provides an arbitrary dielectric constant leaky wave antenna based on alternating sub-arrays, which has the following beneficial effects:

[0016] The new sub-array alternating array design reduces the requirement of high dielectric constant of the substrate for the traditional end-fire leaky wave antenna. The radiating unit couples energy from the metal wire and space at the same time, and the uniformity of the radiation aperture is improved. Under the same array area, a higher end-fire gain can be achieved, and a higher gain-length ratio can be achieved. In addition, the end-fire leaky wave antenna of the present invention can achieve a larger gain bandwidth. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a first structural schematic diagram of the sub-array alternating end-fire leaky wave antenna provided in an embodiment of the present invention.

[0018] Figure 2 It is a top view of the first structure of the sub-array alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0019] Figure 3 It is a theoretical relationship diagram among the first structure subarray directional pattern, array factor directional pattern and array directional pattern of the subarray alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0020] Figure 4 It is a first structural reflection coefficient and gain diagram of the sub-array alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0021] Figure 5 This is the first structural radiation pattern of the sub-array alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0022] Figure 6 It is a second structural schematic diagram of the sub-array alternating end-fire leaky wave antenna provided in an embodiment of the present invention.

[0023] Figure 7 It is a theoretical relationship diagram among the second structure subarray radiation pattern, array factor radiation pattern and array radiation pattern of the subarray alternating end-fire leaky wave antenna provided in an embodiment of the present invention.

[0024] Figure 8 It is a top view of the second structure of the sub-array alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0025] Fig. 9 It is a second structural reflection coefficient and gain diagram of the sub-array alternating end-fire leaky wave antenna provided in an embodiment of the present invention.

[0026] Fig.10 This is the second structural radiation pattern of the sub-array alternating end-fire leaky wave antenna provided by an embodiment of the present invention.

[0027] In the figure: 1. first dielectric substrate; 2. first metal wire; 3. first sub-array; 4. second metal wire; 5. second sub-array; 6. second dielectric substrate; 7. third metal wire; 8. third sub-array; 9. fourth metal wire; 10. fourth sub-array. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] like Figure 1As shown, a first embodiment of the embodiments of the present invention is an end-fire leaky wave antenna with arbitrary dielectric constant based on alternating sub-arrays, comprising an upper metal layer, a first dielectric substrate and a lower metal layer arranged in sequence from top to bottom, wherein the upper metal layer comprises a first metal wire 2 and a first sub-array 3 arranged alternately on both sides of the first metal wire, and the lower metal layer comprises a second metal wire 4 and a second sub-array 5 arranged alternately on both sides of the second metal wire, and the first sub-array and the second sub-array are symmetrical with respect to the axis of the first metal wire and the second metal wire.

[0031] In the embodiment of the present application, the arbitrary dielectric constant end-fire leaky wave antenna based on subarray alternation utilizes space-1st harmonic radiation, and the propagation constant satisfies For the -1st harmonic, the propagation constant satisfies β -1 =k0. Where β is the propagation constant, d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0032] Furthermore, the subarray spacings of the first subarray 3 and the second subarray 5 are the same and satisfy the subarray spacing Where d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0033] The spacing between the radiation elements in the first subarray 3 and the second subarray 5 is the same, and the spacing between the radiation elements satisfies d ele =d / N. Where d is the subarray spacing, and N (N≥1) is the number of radiation units in the subarray.

[0034] Preferably, the radiation units in the sub-arrays of the first sub-array 3 and the second sub-array 5 operate in a non-resonant state, and the radiation units have no effect on the matching performance of the transmission line formed by the first metal wire and the second metal wire, while coupling energy from the upper metal wire, the lower metal wire and the space.

[0035] In the present application, the first dielectric substrate 1 adopts a Rogers 5880 substrate with a dielectric constant of 2.2, and the substrate size is 147.7 mm×11 mm×0.508 mm.

[0036] like Figure 2 , which is a top view of each layer of the first embodiment.

[0037] In the present application, the arbitrary dielectric constant end-fire leaky wave antenna based on subarray alternation comprises five alternately arranged first subarrays 3 and five alternately arranged second subarrays 5. The first subarray 3 and the second subarray 5 comprise the same number of six radiating elements. The subarray spacing is 27.6 mm, the radiating element spacing is 4.6 mm, the radiating element size along the Y direction is 4.5 mm, and the radiating element size along the Z direction is 4.3 mm.

[0038] like Figure 3 As shown, according to the pattern product theorem, the antenna subarray pattern is multiplied by the array factor, the high side lobes of the array factor are eliminated, and the array achieves a stable end-fire pattern.

[0039] like Figure 4 As shown, the -10dB impedance bandwidth of the antenna test is 8.55-9.9GHz, the highest gain tested is 14.1dBi, the gain-length ratio is 6.0, and the 3dB gain bandwidth is 13.0%.

[0040] like Figure 5 Shown are the normalized radiation patterns of the E-plane and H-plane of the antenna of the first embodiment.

[0041] like Figure 6 As shown, the second embodiment of the embodiment of the present invention is an end-fire leaky wave antenna with arbitrary dielectric constant based on alternating subarrays, comprising an upper metal layer, a second dielectric substrate and a lower metal layer arranged in sequence from top to bottom. The upper metal layer comprises a third metal wire 7 and a third subarray 8 arranged alternately on both sides of the third metal wire. The lower metal layer comprises a fourth metal wire 9 and a fourth subarray 10 arranged alternately on both sides of the fourth metal wire. The third subarray and the fourth subarray are symmetrical with respect to the axis of the third metal wire and the fourth metal wire.

[0042] The arbitrary dielectric constant end-fire leaky wave antenna based on subarray alternation utilizes space-1st harmonic radiation, and the propagation constant satisfies For the -1st harmonic, the propagation constant satisfies β -1 =k0. Where β is the propagation constant, d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0043] Furthermore, the sub-array spacings of the third sub-array 8 and the fourth sub-array 10 are the same and satisfy the sub-array spacing Where d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

[0044] The spacing between the radiation units in the third subarray 8 and the fourth subarray 10 is the same, and the spacing between the radiation units satisfies d ele =d / N. Where d is the subarray spacing, and N (N≥1) is the number of radiation units in the subarray.

[0045] Preferably, the radiation units in the subarray operate in a non-resonant state, and the radiation units have no effect on the matching performance of the transmission lines formed by the upper metal wires and the lower metal wires, while coupling energy from the upper metal wires, the lower metal wires and the space.

[0046] In the present application, the second dielectric substrate 6 adopts a TFA-1020 substrate with a dielectric constant of 2.2 and a dielectric constant of 10.5, and the substrate size is 176.6 mm×9.03 mm×0.635 mm.

[0047] like Figure 7 , which is a top view of each layer of the second embodiment. In the present application, the arbitrary dielectric constant end-fire leaky wave antenna based on subarray alternation includes twenty alternating third subarrays 8 and twenty alternating fourth subarrays 10. The third subarray 8 and the fourth subarray 10 only include one radiating unit. The subarray spacing is 8.4 mm, the size of the radiating unit along the Y direction is 3.4 mm, and the size of the radiating unit along the Z direction is 6 mm.

[0048] like Figure 8 As shown, according to the pattern product theorem, the antenna subarray pattern is multiplied by the array factor, and the array achieves a stable end-fire pattern.

[0049] like Fig. 9 As shown, the -10dB impedance bandwidth of the antenna test is 8.5-10.5GHz, the highest gain tested is 14.4dBi, the gain-length ratio is 5.4, and the 3dB gain bandwidth is 8.6%.

[0050] like Fig.10 Shown are the normalized radiation patterns of the E-plane and H-plane of the antenna of the second embodiment.

[0051] The basic principles and main features of the present invention and the advantages of the present invention are shown and described above. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0052] Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is therefore intended that all changes falling within the meaning and range of equivalent elements of the claims are included in the present invention.

[0053] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An arbitrary dielectric constant end-fire leaky wave antenna based on subarray alternation, characterized in that: The invention comprises an upper metal layer, a dielectric substrate and a lower metal layer arranged in sequence from top to bottom; the upper metal layer comprises a first metal wire and a first sub-array arranged alternately on both sides of the first metal wire; the lower metal layer comprises a second metal wire and a second sub-array arranged alternately on both sides of the second metal wire; the first sub-array and the second sub-array are symmetrical with respect to the axis of the first metal wire or the second metal wire; each sub-array of the first sub-array and the second sub-array comprises the same number of one or more radiation units.

2. The end-fire leaky wave antenna with arbitrary dielectric constant based on subarray alternation according to claim 1, characterized in that: When each of the first subarray and the second subarray includes one radiation unit, the dielectric constant of the dielectric substrate is greater than 4 and less than 9.

3. The end-fire leaky wave antenna with arbitrary dielectric constant based on subarray alternation according to claim 1, characterized in that: When each of the first sub-array and the second sub-array includes a plurality of radiation units, the dielectric constant of the dielectric substrate ranges from 1 to 4.

4. The end-fire leaky wave antenna with arbitrary dielectric constant based on subarray alternation according to claim 1, characterized in that: The end-fire leaky wave antenna utilizes space-1st harmonic radiation, and the propagation constant satisfies For the -1st harmonic, the propagation constant satisfies β -1 =k0, where β is the propagation constant, d is the subarray spacing between the first subarray and the second subarray, and ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

5. The end-fire leaky wave antenna with arbitrary dielectric constant based on sub-array alternation according to claim 1, characterized in that: The subarray spacing of the first subarray and the second subarray is the same, and the subarray spacing satisfies Where d is the subarray spacing, ε r is the dielectric constant of the dielectric substrate, and k0 is the phase constant.

6. The end-fire leaky wave antenna with arbitrary dielectric constant based on subarray alternation according to claim 1, characterized in that: When a subarray includes a plurality of the radiating elements, the spacing between the radiating elements in the subarray is the same, and the spacing between the radiating elements satisfies d ele =d / N, where d is the subarray spacing, N is the number of radiation units in the subarray, and N≥1.

7. The end-fire leaky wave antenna with arbitrary dielectric constant based on sub-array alternation according to claim 1, characterized in that: The radiation unit operates in a non-resonant state.

8. The end-fire leaky wave antenna with arbitrary dielectric constant based on sub-array alternation according to claim 1, characterized in that: The radiation unit couples energy from the upper metal line, the lower metal line and the space simultaneously.

9. The end-fire leaky wave antenna with arbitrary dielectric constant based on sub-array alternation according to claim 1, characterized in that: The radiation unit has no influence on the matching performance of the transmission line formed by the upper metal wire and the lower metal wire.

10. The end-fire leaky wave antenna with arbitrary dielectric constant based on sub-array alternation according to claim 3, characterized in that: The subarray patterns of the first subarray and the second subarray suppress side lobes generated by the array factor, so that the antenna array radiates a stable end-fire pattern.

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