CN209948058U - Electrically large microstrip array antenna with large spacing and low grating lobes based on high-order odd-mode resonance - Google Patents

Abstract

A large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance, comprising: a radiating element array stacked from top to bottom, an upper-layer dielectric substrate, a lower-layer metal floor, a lower-layer dielectric substrate, and a feeding network, The input end of the feeding network is used as the input end of the antenna, and the output end of the feeding network is connected to the _radiating element array, and the _radiating element array is connected to the feeding network through the metal probe. The radiation element array described above includes 8 square patch antenna units arranged horizontally at equal intervals, and the side length of the square patch antenna units is 1.08 times the wavelength of the center frequency of the working frequency band and the spacing between adjacent square patch antenna units is 1.8 times the wavelength of the center frequency of the working frequency band. The utility model can effectively avoid the influence of the high-order odd-order mode side lobes and the large array element spacing on the directional characteristics of the array antenna, so that the high-order odd-order mode with large side lobes can be normally used in the array antenna design.

Description

Electrically large microstrip array antenna with large spacing and low grating lobes based on high-order odd-mode resonance

technical field

The utility model belongs to the technical field of antennas, in particular to a large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance.

Background technique

As an important part of information transmission between wireless communication systems, microstrip antennas are widely used because of their small size and low profile. With the advent of the 5G era, low-frequency spectrum resources are becoming increasingly scarce, and the development of microstrip antennas to high-frequency millimeter waves and sub-millimeter waves has become an inevitable trend. Since the size of the antenna is half of the wavelength of the resonant frequency, as the operating frequency of the antenna increases, the size of the microstrip antenna will gradually decrease, which will bring certain problems to the processing and application of the antenna. On the one hand, because the size of the antenna is too small, it will place higher requirements on the processing technology. On the other hand, if the size of the antenna is too small, it will be difficult to meet the requirements of fixed installation of some devices. In order to solve these problems caused by the too small size of the antenna, it is necessary to break through the limitation that the size of the antenna is one-half the wavelength of the resonant frequency, and design a microstrip antenna with the characteristics of electric large size. That is to say, at the same resonant frequency, the size of the electrically large antenna is larger than that of the traditional antenna.

The resonance mode of the traditional square patch antenna is the TM ₁₀ /TM ₀₁ mode. However, for high-order odd modes such as TM _n0 /TM _0n (n=3, 5, 7…), it not only has a higher gain, but also has a TM ₁₀ /TM ₀₁ mode similar normal phase radiation characteristics. More importantly, under the same size, the operating frequency of the TM _n0 /TM _0n mode is about n times that of the TM ₁₀ /TM ₀₁ mode, which is very beneficial to the realization of electrically large-sized antennas. However, due to the large side lobes of the TM _n0 /TM _0n die, this makes it difficult to apply higher-order modes to antenna design. At the same time, in the face of the current complex communication environment, it is also a practical need to design an array antenna with high gain characteristics. Obviously, the application of high-order odd-order modes to the design of array antennas will have certain practical significance, which can reduce the requirements of the antenna on the processing technology to a certain extent, facilitate the fixed installation of the antenna on the equipment, and solve the problem of high-order Practical application of odd-order modes.

Utility model content

The utility model provides an electric large microstrip array antenna with large spacing and low grating lobes based on high-order odd-order mode resonance. The utility model can normally apply the high-order odd-order mode to the design of the array antenna, and effectively avoids the influence of the side-lobe of the high-order odd-order mode and the large array element spacing on the directional characteristics of the array antenna without loading any structure.

The technical scheme adopted by the utility model is:

A large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance, comprising: a radiating element array stacked from top to bottom, an upper-layer dielectric substrate, a lower-layer metal floor, a lower-layer dielectric substrate, and a feeding network, The input end of the feeding network is used as the input end of the antenna, the output end of the feeding network is connected to the radiating element array, and the radiating element array is connected to the feeding network through a metal probe, and the high-order odd-order mode is TM ₃₀ /TM ₀₃ mode, the radiation unit array includes 8 square patch antenna units arranged horizontally at equal intervals, and the side length of the square patch antenna unit is 1.08 times the wavelength of the center frequency of the working frequency band and adjacent square patches The spacing of the antenna elements is 1.8 times the wavelength of the center frequency of the working frequency band.

The beneficial effects of the present utility model are:

The utility model can realize the normal application of the high-order odd-order mode to the array antenna, and effectively avoid the influence of the side-lobe of the high-order odd-order mode and the large array element spacing on the directional characteristics of the array antenna. Since high-order odd-order molds have larger side lobes (refer to Figure 7a), which will make it difficult for high-order odd-order molds to be applied normally, the present invention uses eight side lengths that are 1.08 times the center frequency wavelength of the working frequency band. The antenna elements are arranged according to a specific spacing, so that the high-order odd-order mode with large side lobes can be normally applied to the array antenna design without loading any structure; the null area and the array factor grid of the high-order odd-order mode element pattern are used. The lobes are superimposed to reduce the grating lobes of the array antenna pattern (refer to Figure 7b). Specifically, the radiating element array of the present invention is composed of 8 square patch antenna elements with electrical large size characteristics, which are arranged at equal intervals and horizontally. , the size of the square patch antenna unit is 1.08 times the wavelength of the center frequency of the working frequency band, the array element spacing of the radiating element array is 1.8 times the wavelength of the center frequency of the working frequency band, and the high-order odd-order mode is TM ₃₀ /TM ₀₃ mode . Since the antenna unit based on the high-order odd-order mode has the characteristic of being electrically large, the utility model realizes the purpose of expanding the size of the array antenna under the same working frequency, and reduces the requirements on the processing technology of the high-frequency millimeter-wave antenna. At the same time, under the condition that the unit spacing is 1.8 times the wavelength of the center frequency of the working frequency band, the utility model utilizes the null region of the pattern of the high-order odd-order mode, which reduces the side lobes of the high-order odd-order mode and the large array very well. The effect of element spacing on the directional characteristics of an array antenna.

Description of drawings

FIG. 1 is a schematic diagram of a layered structure of a large-spacing and low-grating-lobe electric-large microstrip array antenna substrate based on high-order odd-order mode resonance in this embodiment.

FIG. 2 is a schematic diagram of the overall layered structure of the large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 3 is a schematic structural diagram of a large-spacing, low-grating-lobe electric-large microstrip array antenna radiating element array based on high-order odd-order mode resonance and an upper-layer dielectric substrate in this embodiment.

FIG. 4a is a schematic diagram of the structure of the lower metal floor of the large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 4b is a schematic diagram of a partial structure of the lower metal floor of the large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 5a is a schematic structural diagram of a feeding network of a large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

Figure 5b is a schematic structural diagram of a 1:1 one-to-two-way microstrip power divider for a large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 5c is a schematic structural diagram of the second 1:1 one-to-two-way microstrip power divider of the large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 5d is a schematic structural diagram of the third 1:1 one-to-two-way microstrip power divider of the large-spacing low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 5e is a schematic structural diagram of the output port of the large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-mode resonance in this embodiment.

FIG. 6 is a graph showing the return loss of an electrically large microstrip array antenna with large spacing and low grating lobes based on high-order odd-order mode resonance in this embodiment.

FIG. 7a is an E-plane pattern of a high-order odd-order mode of a large-spacing, low-grating-lobe electrically large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 7b is a normalized radiation pattern of large grating lobes existing in the large-spacing low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

FIG. 7c is a normalized radiation pattern at 18.5 GHz after the large grating lobes are eliminated by the large-spacing and low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance in this embodiment.

Detailed ways

A large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance, comprising: a radiating element array 1 stacked from top to bottom, an upper dielectric substrate 2, a lower metal floor 3, a lower dielectric substrate 4 and A feeding network 5, the input end of the feeding network 5 is used as an antenna input end, and the output end of the feeding network 5 is connected to the radiating element array 1, and the radiating element array 1 is connected to the feeding network 5 through the metal probe p , the high-order odd-order mode is TM ₃₀ /TM ₀₃ mode, the radiation element array 1 includes 8 square patch antenna units 11 arranged horizontally at equal intervals, and the side lengths of the square patch antenna units 11 It is 1.08 times the wavelength of the center frequency of the working frequency band, and the spacing d of the adjacent square patch antenna units is 1.8 times the wavelength of the center frequency of the working frequency band. shape groove, so that the metal probe p passes through the lower metal floor 3 without contact;

The feeding network 5 includes a first-stage one-to-two-way microstrip power divider 51 and the input end I of the first-stage one-to-two-way microstrip power divider 51 is used as the input end of the feeding network 5, The output ends of the first-stage one-to-two-way microstrip power divider 51 are respectively connected with the second-stage one-to-two-way microstrip power divider 52, and the second-stage one-to-two-way microstrip power divider 52 Each output end is respectively connected with a third-stage one-part two-way microstrip power divider 53, and the eight output ends O of the third-stage one-part two-way microstrip power divider 53 are used as the output ends of the feeding network 5. are respectively connected with 8 square patch antenna units 11;

The output end O of each third-stage one-to-two-way microstrip power divider 53 is laterally deviated from the center of the square patch by 2mm;

The output end O of the third-stage one-to-two-way microstrip power divider 53 is in the shape of a circle 54 and is connected with a metal probe, the metal probe penetrates the lower dielectric substrate 4, the lower metal floor 3 and all the The upper dielectric substrate 2 feeds the radiation element array 1 .

Below in conjunction with the accompanying drawings, the specific embodiments of the present utility model are described in more detail:

1 and 2, a large-spacing, low-grating-lobe electric-large microstrip array antenna based on high-order odd-order mode resonance includes a radiating element array 1 stacked from top to bottom, an upper dielectric substrate 2, and a lower metal floor 3 , the lower dielectric substrate 4 and the feeding network 5, the input end of the feeding network 5 is used as the antenna input end, the output end of the feeding network 5 is connected to the radiation element array 1, the radiation element array 1 and the feeding network 5 There is a metal probe p passing through the upper intermediate metal floor 2, the lower metal floor 3 and the lower dielectric substrate 4 therebetween;

Further, with reference to FIG. 3 , the radiating element array 1 includes 8 square patch antenna units arranged horizontally at equal intervals with electrical large size characteristics, and the side length of the square patch antenna unit is 1.08 times the center frequency of the working frequency band. The wavelength and the equal spacing d of adjacent square patch antenna units are 1.8 times the wavelength of the center frequency of the working frequency band, and the high-order odd-order mode is the TM ₃₀ /TM ₀₃ mode.

Further, with reference to Fig. 4a and Fig. 4b, the lower metal floor 3 is engraved with 8 circular grooves for accommodating probes.

Further, with reference to Fig. 5a, Fig. 5b, Fig. 5c, Fig. 5d and Fig. 5e, the feed network 5 includes a first-stage one-part two-way microstrip power divider 51 and the first-stage one-part two-way microstrip The input end I of the power divider 51 is used as the input end of the unequal power distribution network 5, and the output end of the first-stage one-part two-way microstrip power divider 51 is respectively connected with the second-stage one-part two-way microstrip power divider 51. The band power divider 52 is connected to each output end of the second-stage one-to-two-way microstrip power divider 52, and a third-stage one-to-two-way microstrip power divider 53 is respectively connected. The eight output ends O of the microstrip power divider 53 are respectively connected to the eight square patch antenna units 11 as the output ends of the unequal power distribution network 5 .

In this embodiment, the energy of the array antenna is input from the feeding network 5 to excite the radiation element array 1, so that the square antenna elements in the radiation array element 1 all work in the high-order odd-order mode. When the size of the square antenna unit is 1.08 times the wavelength of the center frequency of the working frequency band, the array element spacing of the radiation array unit 1 is 1.8 times the wavelength of the center frequency of the working frequency band, and the high-order odd-order mode is the TM ₃₀ /TM ₀₃ mode . Since there are two null areas in the E-plane pattern of the square antenna unit, the present invention utilizes the null area of the unit pattern to overlap with the array factor grating lobes, which prevents serious grating lobes from appearing in the pattern of the present invention. .

6, 7a and 7b, the operating frequency range of the present utility model is 18.3GHz to 18.7GHz, under the premise that the square patch units are arranged at equal intervals and the array element spacing is 1.8 times the wavelength of the center frequency of the working frequency band , the grating lobe is less than -15dB in the whole working bandwidth. It not only effectively expands the size of the high-frequency millimeter-wave array antenna, but also reduces the requirements for processing technology, and at the same time effectively avoids the influence of high-order odd-order mode side lobes and large array element spacing on the directional characteristics of the array antenna, making the antenna with large side lobes. Higher-order odd-order modes can normally be used in the design of array antennas.

Claims (5)

1. A large-space low-grating lobe electric large microstrip array antenna based on high-order odd-order mode resonance comprises: the antenna comprises a radiation unit array (1), an upper dielectric substrate (2), a lower metal floor (3), a lower dielectric substrate (4) and a feed network (5) which are stacked from top to bottom, wherein the input end of the feed network (5) is used as an antenna input end, the output end of the feed network (5) is connected to the radiation unit array (1), the radiation unit array (1) is connected with the feed network (5) through a metal probe (p), and the antenna is characterized in that the high-order odd-order mode is TM₃₀/TM₀₃The radiating element array (1) comprises 8 square patch antenna units (11) which are transversely arranged at equal intervals, the side length of each square patch antenna unit (11) is 1.08 times of the central frequency wavelength of the working frequency band, and the interval (d) between every two adjacent square patch antenna units is 1.8 times of the central frequency wavelength of the working frequency band.

2. The large-pitch low-grating-lobe electrically large microstrip array antenna based on high-order odd-order mode resonance according to claim 1, wherein a circular groove is opened on the lower metal floor (3) to allow the metal probe (p) to pass through the lower metal floor (3) without contact.

3. The large-gap low-grating-lobe electric large microstrip array antenna based on the high-order odd-order mode resonance as claimed in claim 2, wherein the feed network (5) comprises a first-stage one-to-two-way microstrip power divider (51), an input end (I) of the first-stage one-to-two-way microstrip power divider (51) is used as an input end of the feed network (5), output ends of the first-stage one-to-two-way microstrip power divider (51) are respectively connected with a second-stage one-to-two-way microstrip power divider (52), output ends of the second-stage one-to-two-way microstrip power divider (52) are respectively connected with a third-stage one-to-two-way microstrip power divider (53), and 8 output ends (O) of the third-stage one-to-two-way microstrip power divider (53) are used as output ends of the feed network (5) and are respectively connected with 8 square patch antenna units (11.

4. The large-pitch low-grating-lobe electrically large microstrip array antenna based on the higher-order odd-order mode resonance of claim 3, wherein the output end (O) of each third-stage two-way microstrip power divider (53) is laterally deviated from the center of the square patch by 2 mm.

5. The large-pitch low-grating-lobe electric large microstrip array antenna based on the higher-order odd-order mode resonance as claimed in claim 4, wherein the output end (O) of the third-level two-way microstrip power divider (53) is circular (54) and connected with the metal probe (p), and the metal probe (p) penetrates through the lower dielectric substrate (4), the lower metal floor (3) and the upper dielectric substrate (2) and feeds the radiation element array (1).

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