High-degree-of-freedom multi-antenna structure with decoupling function

Abstract

The invention discloses a high-degree-of-freedom multi-antenna structure with a decoupling function, and the structure comprises a rectangular metal patch array which is formed by uniformly distributing m * n rectangular metal patches with the same size at intervals according to m rows and n columns, every two adjacent rectangular metal patches in each row and every two adjacent rectangular metal patches in each column are connected through a switch, in an initial state, all the switches are in an off state, the number of antennas included in the high-degree-of-freedom multi-antenna structure is recorded as N, and N is a positive integer; the N antennas are constructed by selecting N columns of rectangular metal patches from the rectangular metal patch array as N antenna construction columns, and the decoupling structure is constructed from other columns of rectangular metal patches except the N antenna construction columns in the rectangular metal patch array; the method has the advantages that the degree of freedom of design and optimization is high, and flexible expansion can be achieved.

Description

Technical Field

[0001] The invention relates to a multi-antenna structure, in particular to a high-freedom multi-antenna structure with a decoupling function. Background Art

[0002] In the context of increasingly tight spectrum resources and growing communication needs, traditional fixed-structure antennas, although they perform well in specific applications, have obvious limitations in adapting to changing communication environments and frequency diversity, which places requirements on the freedom of antennas. At the same time, with the increase in mobile communication standards and technological evolution, the importance of MIMO multi-antenna systems in the field of communications has gradually become prominent. However, the application of MIMO multi-antenna systems faces the coupling problem caused by the close arrangement of antennas. At present, MIMO multi-antenna systems need to meet the requirements of different application frequency bands such as 2G / 3G / 4G, 5G, Wi-Fi, and Bluetooth. Therefore, the MIMO multi-antenna system needs to have a high degree of freedom while also having a good decoupling structure to reduce the coupling effect between its internal antennas in multiple frequency bands.

[0003] The document “Fatima Amin, Rashid Saleem, Tayyab Shabbir, et.al. A Compact Quad-Element UWB-MIMO Antenna System with Parasitic Decoupling Mechanism [J]. Applied Sciences, 2019, 9(11): 2371.” introduces a MIMO multi-antenna system, which is composed of multiple antenna structures and multiple decoupling structures, wherein each antenna structure is a semi-elliptical four-element ultra-wideband multiple-input multiple-output structure, and each decoupling structure is implemented by a horizontal parasitic decoupling strip and a dumbbell-shaped stub structure. In this MIMO multi-antenna system, the antenna structure is fixed. When the working frequency band needs to be increased or changed, the antenna structure cannot be reconstructed and can only be redesigned. In addition, its decoupling structure is also fixed and immutable. Once the antenna structure changes, its decoupling structure also fails and needs to be redesigned. Therefore, the above-mentioned MIMO multi-antenna system has a very low degree of freedom in design and optimization and cannot be flexibly expanded. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a high degree of freedom multi-antenna structure with a decoupling function which has a high degree of freedom in design and optimization and can realize flexible expansion.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a high-degree-of-freedom multi-antenna structure with a decoupling function, including a rectangular metal patch array, wherein the rectangular metal patch array is formed by m*n rectangular metal patches of the same size uniformly distributed in m rows and n columns, wherein * represents a multiplication symbol, m and n are both integers, and m>5, n>4, and every two adjacent rectangular metal patches in each row and every two adjacent rectangular metal patches in each column are connected by a switch, and in the initial state, all switches are in an off state. The number of antennas included in the high-degree-of-freedom multi-antenna structure is recorded as N, N is an integer greater than or equal to 2, N columns of rectangular metal patches are selected from the rectangular metal patch array as N antenna building columns, a required number of rectangular metal patches are selected from each antenna building column, and a switch between any two adjacent rectangular metal patches from the selected required number of rectangular metal patches is closed to build an antenna, thereby forming N antennas. After the N antennas are formed, a decoupling structure is built from the other columns of rectangular metal patches in the rectangular metal patch array except the N antenna building columns, and the decoupling structure makes the mutual admittance of any two antennas at each operating frequency point meet the design requirements.

[0006] The high-freedom multi-antenna structure with a decoupling function also includes a dielectric substrate, a first metal ground, a second metal ground and a plurality of metallized through holes. The dielectric substrate is a rectangular parallelepiped structure, with the length direction of the dielectric substrate as the front-to-back direction, the width direction as the left-to-right direction, and the height direction as the up-down direction; the first metal ground is a rectangular structure, with the length direction of the first metal ground along the left-to-right direction, and the width direction along the front-to-back direction. The first metal ground is attached to the upper surface of the dielectric substrate, the front end of the first metal ground is flush with the front end surface of the dielectric substrate, the left end of the first metal ground is flush with the left end surface of the dielectric substrate, and the right end of the first metal ground is flush with the right end of the dielectric substrate. The first metal ground is flush with the surface of the dielectric substrate, the width of the first metal ground is smaller than the length of the dielectric substrate, the second metal ground is a rectangular structure, the length direction of the second metal ground is along the left-right direction, and the width direction is along the front-back direction, the second metal ground is attached to the lower surface of the dielectric substrate, the front end of the second metal ground is flush with the front end surface of the dielectric substrate, the left end of the second metal ground is flush with the left end surface of the dielectric substrate, the right end of the second metal ground is flush with the right end surface of the dielectric substrate, and the width of the second metal ground is greater than the width of the first metal ground; a plurality of metallized through holes penetrate the first metal ground, the dielectric substrate and the second metal ground from top to bottom, connecting the first metal ground and The second metal ground is connected so that the first metal ground and the second metal ground become equipotential bodies; the plane that makes the dielectric substrate bilaterally symmetrical is called the first symmetry plane, m*n rectangular metal patches are attached to the upper surface of the dielectric substrate, the length direction of each rectangular metal patch is along the left-right direction, the width direction is along the front-back direction, the spacing between two adjacent rectangular metal patches in each row and the spacing between two rectangular metal patches in each column are equal, and the spacing is recorded as d, the front ends of each row of rectangular metal patches are located in the same straight line, and the straight line is parallel to the front end surface of the dielectric substrate, the left ends of each column of rectangular metal patches are located in the same straight line, and the straight line is parallel to the left end surface of the dielectric substrate, and the m rows of rectangular metal patches are connected to the first symmetry plane. The rectangular metal patches are sequentially referred to as the 1st row of rectangular metal patches to the mth row of rectangular metal patches from back to front, and the nth columns of rectangular metal patches are sequentially referred to as the 1st column of rectangular metal patches to the nth column of rectangular metal patches from left to right, the straight line where the rear end of the 1st row of rectangular metal patches is located is located in front of the rear end of the dielectric substrate, the straight line where the front end of the mth row of rectangular metal patches is located is located in the rear side of the rear end of the first metal substrate, and the spacing between the two is d, the straight line where the left end of the first column of rectangular metal patches is located is located on the right side of the plane where the left end face of the dielectric substrate is located; the straight line where the right end of the nth column of rectangular metal patches is located is located on the left side of the plane where the right end face of the dielectric substrate is located, and the rectangular metal patch array is bilaterally symmetrical about the first symmetry plane.

[0007] Each antenna is constructed in the following manner: first select a column of rectangular metal patches in the rectangular metal patch array, select a corresponding number of rectangular metal patches from the mth row of rectangular metal patches in the column, and then close the switches between any two adjacent rectangular metal patches in all the selected rectangular metal patches. At this time, an antenna is constructed, wherein any two antennas select rectangular metal patches in different columns, N antennas are evenly spaced, and there are at least 3 columns of rectangular metal patches between two adjacent antennas; if an antenna is to operate at a single frequency, when the distance between the front end of the rectangular metal patch in the 1st row and the rear end of the rectangular metal patch in the mth row is greater than 1 / 2 wavelength of its operating frequency, in the antenna, the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the last row The antenna selects the entire column of rectangular metal patches when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is less than or equal to 1 / 2 wavelength of its operating frequency; if an antenna is to operate at multiple frequencies, when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is greater than the average value of 1 / 2 wavelength of its multiple operating frequencies, in the antenna, the distance between the front end of the rectangular metal patch in the front row and the back end of the rectangular metal patch in the last row is closest to the average value of 1 / 2 wavelength of its multiple operating frequencies, and when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is less than or equal to the average value of 1 / 2 wavelength of its multiple operating frequencies, the antenna selects the entire column of rectangular metal patches.

[0008] The number of working frequencies of N antennas is recorded as M, and the N antennas are called the 1st antenna to the Nth antenna in order from left to right. The jth antenna needs to be built including K j The decoupling unit of the decoupling branch, K jis an integer greater than or equal to M(N-1), j=1,2,3,…,N; the decoupling units of N antennas constitute the decoupling structure, and the number of decoupling branches included in the decoupling structure is recorded as S, and S is an integer greater than or equal to MN(N-1); for the i-th antenna, i=2,3,…,N-1, the construction area of ​​its decoupling branch is located between the leftmost decoupling branches among all decoupling branches of the antenna and the i+1-th antenna, or between the rightmost decoupling branches among all decoupling branches of the antenna and the i-1-th antenna; for the first antenna, if the antenna is built at the first column of rectangular metal patches, The construction area of ​​its decoupling branch is located between the leftmost decoupling branches among all the decoupling branches of the antenna and the second antenna. If the antenna is not built at the first column of rectangular metal patches, the construction area of ​​its decoupling branch is located between the leftmost decoupling branches among all the decoupling branches of the antenna and the second antenna, or on the left side of the antenna; for the Nth antenna, if the antenna is built at the nth column of rectangular metal patches, the construction area of ​​its decoupling branch is located between the rightmost decoupling branches among all the decoupling branches of the antenna and the N-1th antenna. If the antenna is not built at the nth column of rectangular metal patches, its decoupling branch The construction area is located between the rightmost decoupling branches of the antenna and the N-1th antenna, or on the right side of the antenna; the decoupling unit of any one of the N antennas is respectively constructed in the following manner: the number of rectangular metal patches for constructing the antenna is recorded as a, and any column of rectangular metal patches without other decoupling branches is selected in the construction area of ​​the antenna, and at least 3 rectangular metal patches are selected from the rectangular metal patch in the bth row of the column of rectangular metal patches, and then or all the selected rectangular metal patches, except the rectangular metal patch in the bth row and the rectangular metal patch in the b+1th row, are selected. Except for the switch between them, the switches between any two adjacent rectangular metal patches are closed, and a decoupling branch is built. This decoupling branch is called a parasitic decoupling branch. Alternatively, the switches between any two adjacent rectangular metal patches in all selected rectangular metal patches are closed, and a decoupling branch is built. This decoupling branch is called a self-decoupling branch. If a is an odd number, then either b=ma / 2+1 / 2, or b=ma / 2-1 / 2, or b=ma / 2+3 / 2; if a is an even number, then either b=ma / 2+1, or b=ma / 2, or b=ma / 2+2;When all the decoupling branches of the antenna are built, all the decoupling branches of the antenna are connected according to the following connection method: the column number of the antenna in the rectangular metal patch array is recorded as g, that is, the antenna is built at the g-th column of the rectangular metal patch array, the column number of the decoupling branch of the antenna located on the far left in the rectangular metal patch array is recorded as k, that is, the decoupling branch of the antenna located on the far left is built at the k-th column of the rectangular metal patch array, the column number of the decoupling branch of the antenna located on the far right in the rectangular metal patch array is recorded as h, that is, the decoupling branch of the antenna located on the far right is built at the h-th column of the rectangular metal patch array. shaped metal patch. If the decoupling branches of the antenna are distributed on its left and right sides, then the switches between each adjacent two rectangular metal patches in the h-k+1 rectangular metal patches in the b-th row of the rectangular metal patch array located in the k-th column to the h-th column are closed. If the decoupling branches of the antenna are only distributed on its left side, then the switches between each adjacent two rectangular metal patches in the g-k+1 rectangular metal patches in the b-th row of the rectangular metal patch array located in the k-th column to the g-th column are closed. If the decoupling branches of the antenna are only distributed on its right side, then the switches between each adjacent two rectangular metal patches in the g-k+1 rectangular metal patches in the b-th row of the rectangular metal patch array located in the g-th column to the h-th column are closed. h-g+1 rectangular metal patches, the switches between every two adjacent rectangular metal patches are closed, and at this time, the connection of all the decoupling branches of the antenna is completed; after the connection of all the decoupling branches of the antenna is completed, in the construction area of ​​the antenna, at least one rectangular metal patch that is not used to build its decoupling branch is selected from the rectangular metal patches in the mth row to the rectangular metal patches in the m-2th row of the rectangular metal patch array as the grounding metal patch of the antenna, and each grounding metal patch of the antenna is provided with a metallized through hole that passes through the grounding metal patch, the dielectric substrate and the second metal ground from top to bottom, and the rectangular metal patch located in the front row of each decoupling branch of the antenna is selected Select a connection path that can connect it to a grounding metal patch that is closest to it in a straight line distance, and close the switch between any two adjacent rectangular metal patches on the connection path, so as to realize the connection between each decoupling branch of the antenna and the second metal ground, wherein, when there are multiple grounding metal patches with the closest straight line distance, arbitrarily select one of the grounding metal patches, and select a connection path that uses the least rectangular metal patches for the connection path, and any rectangular metal patch on the connection path cannot appear on the connection path between other decoupling branches of the antenna and the grounding metal patch, and when there are multiple connection paths that meet the conditions and use the least rectangular metal patches, arbitrarily select one of them;Determine whether the switch between each grounding metal patch and its front, rear, left, and right adjacent rectangular metal patches is closed. If a switch is closed, a load is connected in parallel at both ends of the switch. At this time, the decoupling unit of the antenna is completed. When the decoupling units of the N antennas are completed, the decoupling structure is formed. Since each decoupling branch must be connected to a grounding metal patch through a connection path, and there is no duplication of rectangular metal patches in the connection path between any decoupling branch and the grounding metal patch, there are a total of S decoupling branches. The connection path between each decoupling branch and the grounding metal patch is different and includes a load, so there are a total of S loads. After the S loads and load parameters are selected, the mutual admittance of any two antennas at each operating frequency point can meet the design requirements. ;

[0009] Each of the loads is selected from one of capacitance and inductance. When the load is capacitance, the load parameter is the capacitance value. When the load is inductance, the load parameter is the inductance value. Any two loads and load parameters can be the same or different.

[0010] Compared with the prior art, the advantage of the present invention is that a rectangular metal patch array is formed by setting m*n rectangular metal patches of the same size and evenly spaced in m rows and n columns, where * represents a multiplication symbol, m and n are both integers, and m>5, n>4, and every two adjacent rectangular metal patches in each row and every two adjacent rectangular metal patches in each column are connected by a switch. In the initial state, all switches are in the off state, and the number of antennas included in the high-degree-of-freedom multi-antenna structure is recorded as N, where N is an integer greater than or equal to 2, that is, the high-degree-of-freedom multi-antenna structure needs to include N antennas, and at this time, N columns of rectangular metal patches are selected from the rectangular metal patch array as N Antenna building columns, selecting a required number of rectangular metal patches from each antenna building column and closing a switch between any two adjacent rectangular metal patches from the selected required number of rectangular metal patches to build an antenna, thereby forming N antennas. After the N antennas are formed, a decoupling structure is built from the rectangular metal patches in other columns of the rectangular metal patch array except the N antenna building columns. The decoupling structure enables the mutual admittance of any two antennas at each operating frequency point to meet the design requirements, thereby achieving decoupling of the N antennas. Therefore, the design and optimization of the present invention can be achieved through the rectangular metal patch array, and the degree of freedom of design and optimization is high, which can achieve flexible expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is an original antenna structure diagram of a verification example of a high-degree-of-freedom multi-antenna structure with a decoupling function of the present invention;

[0012] FIG. 2( a ) shows a high degree of freedom multi-antenna structure with a decoupling function according to the present invention. Figure 1A complete set of schematic diagrams for a set of examples of decoupling at a single frequency point of 3.5GHz when verifying the original antenna structure of the example;

[0013] FIG. 2( b ) shows a high degree of freedom multi-antenna structure with a decoupling function according to the present invention. Figure 1 A set of simplified schematic diagrams of the example at a single frequency of 3.5GHz for decoupling when verifying the original antenna structure of the example;

[0014] Figure 3 for Figure 1 The S parameter schematic diagram of the original antenna structure of a verification example of a high-freedom multi-antenna structure with a decoupling function of the present invention is shown;

[0015] Figure 4 This is a schematic diagram of S parameters of a decoupling structure built at a single frequency point of 3.5 GHz for a high degree of freedom multi-antenna structure with a decoupling function of the present invention. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below with reference to the accompanying drawings.

[0017] Embodiment 1: Figure 1 As shown, a high-degree-of-freedom multi-antenna structure with a decoupling function includes a rectangular metal patch array 1, wherein the rectangular metal patch array 1 is formed by m*n rectangular metal patches of the same size being evenly spaced in m rows and n columns, wherein * represents a multiplication symbol, m and n are both integers, and m>5, n>4, and each two adjacent rectangular metal patches in each row and each two adjacent rectangular metal patches in each column are connected by a switch, and in an initial state, all switches are in an off state, and the number of antennas included in the high-degree-of-freedom multi-antenna structure is recorded as N, and N is greater than or equal to 2. An integer is selected, N columns of rectangular metal patches are selected from the rectangular metal patch array 1 as N antenna building columns, a required number of rectangular metal patches are selected from each antenna building column and a switch between any two adjacent rectangular metal patches from the selected required number of rectangular metal patches is closed to build an antenna, thereby forming N antennas. After the N antennas are formed, a decoupling structure is built from the other columns of rectangular metal patches in the rectangular metal patch array 1 except the N antenna building columns, and the decoupling structure makes the mutual admittance of any two antennas at each operating frequency meet the design requirements.

[0018] In this embodiment, by controlling the on and off of each switch through an external bias circuit, the connection and disconnection between the two rectangular metal patches connected to the switch can be achieved. The high-freedom multi-antenna structure design and optimization with a decoupling function of the present invention can be achieved through the rectangular metal patch array 1. The design and optimization have a high degree of freedom and can be flexibly expanded.

[0019] Embodiment 2: This embodiment is basically the same as Embodiment 1, except that: in this embodiment, a high degree of freedom multi-antenna structure with a decoupling function further includes a dielectric substrate 2, a first metal ground 3, a second metal ground 4 and a plurality of metallized through holes 5, the dielectric substrate 2 is a rectangular parallelepiped structure, the length direction of the dielectric substrate 2 is used as the front-to-back direction, the width direction is used as the left-to-right direction, and the height direction is used as the up-down direction; the first metal ground 3 is a rectangular structure, the length direction of the first metal ground 3 is along the left-to-right direction, and the width direction is along the front-to-back direction, the first metal ground 3 is attached to the upper surface of the dielectric substrate 2, the front end of the first metal ground 3 is flush with the front end surface of the dielectric substrate 2, and the left end of the first metal ground 3 is flush with the left end surface of the dielectric substrate 2 The first metal ground 3 is flush with the right end surface of the dielectric substrate 2, the width of the first metal ground 3 is smaller than the length of the dielectric substrate 2, the second metal ground 4 is a rectangular structure, the length direction of the second metal ground 4 is along the left-right direction, and the width direction is along the front-back direction. The second metal ground 4 is attached to the lower surface of the dielectric substrate 2, the front end of the second metal ground 4 is flush with the front end surface of the dielectric substrate 2, the left end of the second metal ground 4 is flush with the left end surface of the dielectric substrate 2, the right end of the second metal ground 4 is flush with the right end surface of the dielectric substrate 2, and the width of the second metal ground 4 is greater than the width of the first metal ground 3; a plurality of metallized through holes 5 penetrate the first metal ground 3, the dielectric substrate 2 and the second metal ground 4 from top to bottom, connecting the first metal ground 3 and the second metal ground 4. The two metal grounds 4 are connected, so that the first metal ground 3 and the second metal ground 4 form an equipotential body; the plane that makes the dielectric substrate 2 bilaterally symmetrical is called the first symmetry plane, m*n rectangular metal patches are attached to the upper surface of the dielectric substrate 2, the length direction of each rectangular metal patch is along the left-right direction, the width direction is along the front-back direction, the spacing between two adjacent rectangular metal patches in each row and the spacing between two rectangular metal patches in each column are equal, and the spacing is recorded as d, the front ends of each row of rectangular metal patches are located in the same straight line, and the straight line is parallel to the front end surface of the dielectric substrate 2, the left ends of each column of rectangular metal patches are located in the same straight line, and the straight line is parallel to the left end surface of the dielectric substrate 2, and the m rows of rectangular metal patches are connected. The metal patches are sequentially referred to as the 1st row of rectangular metal patches to the mth row of rectangular metal patches from back to front, and the nth column of rectangular metal patches are sequentially referred to as the 1st column of rectangular metal patches to the nth column of rectangular metal patches from left to right. The straight line where the rear end of the 1st row of rectangular metal patches is located is located in front of the rear end of the dielectric substrate 2, the straight line where the front end of the mth row of rectangular metal patches is located is located in the rear of the rear end of the first metal ground 3, and the spacing between the two is d. The straight line where the left end of the first column of rectangular metal patches is located is located on the right side of the plane where the left end surface of the dielectric substrate 2 is located; the straight line where the right end of the nth column of rectangular metal patches is located is located on the left side of the plane where the right end surface of the dielectric substrate 2 is located, and the rectangular metal patch array 1 is bilaterally symmetrical about the first symmetry plane.

[0020] In this embodiment, each antenna is constructed in the following manner: first select a column of rectangular metal patches in the rectangular metal patch array 1, select a corresponding number of rectangular metal patches from the mth row of rectangular metal patches in the column, and then close the switches between any two adjacent rectangular metal patches in all the selected rectangular metal patches. At this time, an antenna is constructed, wherein any two antennas select rectangular metal patches in different columns, N antennas are evenly spaced, and there are at least 3 columns of rectangular metal patches between two adjacent antennas; if an antenna is to operate at a single frequency, when the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the mth row is greater than half the wavelength of its operating frequency, in the antenna, the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the last row The distance is closest to 1 / 2 wavelength of the required operating frequency, and when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is less than or equal to 1 / 2 wavelength of its operating frequency, the antenna selects the entire column of rectangular metal patches; if an antenna is to operate at multiple frequencies, when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is greater than the average value of 1 / 2 wavelength of its multiple operating frequencies, in the antenna, the distance between the front end of the rectangular metal patch in the front row and the back end of the rectangular metal patch in the last row is closest to the average value of 1 / 2 wavelength of its multiple operating frequencies, and when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is less than or equal to the average value of 1 / 2 wavelength of its multiple operating frequencies, the antenna selects the entire column of rectangular metal patches.

[0021] In this embodiment, the number of working frequencies of N antennas is recorded as M, and the N antennas are referred to as the first antenna to the Nth antenna in order from left to right. The jth antenna needs to be built including K j The decoupling unit of the decoupling branch, K jis an integer greater than or equal to M(N-1), j = 1, 2, 3, ..., N; the decoupling units of the N antennas constitute a decoupling structure, and the number of decoupling branches included in the decoupling structure is recorded as S, and S is an integer greater than or equal to MN(N-1); for the i-th antenna, i = 2, 3, ..., N-1, the construction area of ​​its decoupling branch is located between the leftmost decoupling branch among all the decoupling branches of the antenna and the i+1-th antenna, or between the rightmost decoupling branch among all the decoupling branches of the antenna and the i-1-th antenna; for the first antenna, if the antenna is built at the first column of rectangular metal patches, its decoupling branch The construction area of ​​the decoupling branch is located between the leftmost decoupling branches among all the decoupling branches of the antenna and the second antenna. If the antenna is not built at the first column of rectangular metal patches, the construction area of ​​the decoupling branch is located between the leftmost decoupling branches among all the decoupling branches of the antenna and the second antenna, or on the left side of the antenna; for the Nth antenna, if the antenna is built at the nth column of rectangular metal patches, the construction area of ​​the decoupling branch is located between the rightmost decoupling branches among all the decoupling branches of the antenna and the N-1th antenna. If the antenna is not built at the nth column of rectangular metal patches, the construction area of ​​the decoupling branch is located between the rightmost decoupling branches among all the decoupling branches of the antenna and the N-1th antenna. The area is located between the rightmost decoupling branches of all decoupling branches of the antenna and the N-1th antenna, or on the right side of the antenna; the decoupling unit of any one of the N antennas is constructed in the following manner: the number of rectangular metal patches for constructing the antenna is recorded as a, and any column of rectangular metal patches without other decoupling branches is selected in the construction area of ​​the antenna, and at least 3 rectangular metal patches are selected from the rectangular metal patch in the bth row of the column of rectangular metal patches, and then or among all the selected rectangular metal patches, except for the rectangular metal patch in the bth row and the rectangular metal patch in the b+1th row, the rectangular metal patch is selected. Except for the switch between the two adjacent rectangular metal patches, the switches between any two adjacent rectangular metal patches are closed, and a decoupling branch is built. This decoupling branch is called a parasitic decoupling branch. Alternatively, among all the selected rectangular metal patches, the switches between any two adjacent rectangular metal patches are closed, and a decoupling branch is built. This decoupling branch is called a self-decoupling branch. If a is an odd number, then either b=ma / 2+1 / 2, or b=ma / 2-1 / 2, or b=ma / 2+3 / 2; if a is an even number, then either b=ma / 2+1, or b=ma / 2, or b=ma / 2+2;When all the decoupling branches of the antenna are built, all the decoupling branches of the antenna are connected according to the following connection method: the column number of the antenna in the rectangular metal patch array 1 is recorded as g, that is, the antenna is built at the g-th column of the rectangular metal patch array 1, the column number of the leftmost decoupling branch of the antenna in the rectangular metal patch array 1 is recorded as k, that is, the leftmost decoupling branch of the antenna is built at the k-th column of the rectangular metal patch array 1, the column number of the rightmost decoupling branch of the antenna in the rectangular metal patch array 1 is recorded as h, that is, the rightmost decoupling branch of the antenna is at the h-th column of the rectangular metal patch array 1 Construction, if the decoupling branches of the antenna are distributed on its left and right sides, then the switches between each two adjacent rectangular metal patches in the h-k+1 rectangular metal patches in the b-th row of the rectangular metal patch array 1 located in the k-th column to the h-th column are closed; if the decoupling branches of the antenna are only distributed on its left side, then the switches between each two adjacent rectangular metal patches in the g-k+1 rectangular metal patches in the b-th row of the rectangular metal patch array 1 located in the k-th column to the g-th column are closed; if the decoupling branches of the antenna are only distributed on its right side, then the switches between each two adjacent rectangular metal patches in the h-g+1 rectangular metal patches in the b-th row of the rectangular metal patch array 1 located in the g-th column to the h-th column are closed. In the rectangular metal patch, the switch between each two adjacent rectangular metal patches is closed, and at this time, the connection of all the decoupling branches of the antenna is completed; after the connection of all the decoupling branches of the antenna is completed, in the construction area of ​​the antenna, at least one rectangular metal patch that is not used to build its decoupling branch is selected from the rectangular metal patch in the mth row to the rectangular metal patch in the m-2th row located in the rectangular metal patch array 1 as the grounding metal patch of the antenna, and each grounding metal patch of the antenna is provided with a metallized through hole 5 that passes through the grounding metal patch, the dielectric substrate 2 and the second metal ground 4 from top to bottom, and the rectangular metal patch located in the front row of each decoupling branch of the antenna is selected to be able to be connected to the grounding metal patch. A connection path connected to a grounding metal patch that is closest to it in a straight line distance, and the switch between any two adjacent rectangular metal patches on the connection path is closed, so as to realize the connection between each decoupling branch of the antenna and the second metal ground 4, wherein, when there are multiple grounding metal patches with the closest straight line distance, one of the grounding metal patches is arbitrarily selected, and the connection path selects a connection path that uses the least rectangular metal patches, and any rectangular metal patch on the connection path cannot appear on the connection path between other decoupling branches of the antenna and the grounding metal patch, and when there are multiple connection paths that meet the conditions and use the least rectangular metal patches, one of them is arbitrarily selected;Determine whether the switch between each grounded metal patch and the rectangular metal patches adjacent to it in front, behind, left, and right is closed. If a switch is closed, a load is connected in parallel at both ends of the switch. At this time, the decoupling unit of the antenna is completed. When the decoupling units of N antennas are completed, a decoupling structure is formed. Since each decoupling branch must be connected to a grounded metal patch through a connection path, and there is no duplication of rectangular metal patches in the connection path between any decoupling branch and the grounded metal patch, there are a total of S decoupling branches. The connection path between each decoupling branch and the grounded metal patch is different and includes a load, so there are a total of S loads. After the S loads and load parameters are selected, the mutual admittance of any two antennas at each operating frequency can meet the design requirements. ;

[0022] In this embodiment, each load selects one from capacitance and inductance. When the load is capacitance, the load parameter is the capacitance value. When the load is inductance, the load parameter is the inductance value. Any two loads and load parameters can be the same or different.

[0023] The load parameters of each load can be obtained based on the load parameter determination method disclosed in the Chinese patent with publication number CN114759345A, entitled A decoupling structure with tunable multiple frequencies between two antennas based on a parasitic body. Among them, since the load parameter determination disclosed in the decoupling structure with tunable multiple frequencies between two antennas based on a parasitic body is aimed at two antennas, and the load parameters in the high-freedom multi-antenna structure with decoupling function of the present invention are aimed at N antennas, and decoupling is required between any two antennas, therefore, when using the load parameter determination method disclosed in the decoupling structure with tunable multiple frequencies between two antennas based on a parasitic body to determine the load parameters in the high-freedom multi-antenna structure with decoupling function of the present invention, firstly perform steps (1)-(11) once for each two antennas to obtain the mutual admittance Y1'2(f e ), where e = 1, 2…M; then the following operations are performed for any two of the N antennas:

[0024] Select two antennas and set the intermediate parameter D(f e ), let D(f e )={Re{Y1'2(f e )}} 2 +{Im{Y1'2(f e )}} 2 , where Re{Y1'2(f e )} is Y1'2(f e ), Im{Y1'2(f e )} is Y1'2(f e); for the first frequency point, the reactance XL of the u-th load u (f1) Randomly assign values ​​in the range (c1, c2), where u = 1, 2…S, and the range of c1 is (-1×10 6 ,-1×10 4 ), the value range of c2 is (1×10 -4 ,1×10 8 ), if the reactance value of the u-th load is positive, then the load is determined to be inductor, and then the reactance value of the u-th load at the e-th frequency point is If the reactance value of the u-th load is negative, then the load is determined to be a capacitor, and the reactance value of the u-th load at the e-th frequency is At this time, the mutual admittance formula of the two antennas obtained in steps (1)-(11) is used to obtain Y1'2(f e ), take Y1'2(f e ) to obtain the intermediate parameter D(f e ), then we get the distance between the two antennas D(f1) to D(f M ).

[0025] After performing the above operation on every two antennas in the N antennas, the above operation is repeated N(N-1) times, and a set of D(f1) to D(f2) is obtained each time. M ), so we get N(N-1) groups D(f1) to D(f M ), that is, N(N-1)M intermediate parameters. Construct a set D for storing data, and store the current N(N-1) groups D(f1) to D(f M ) The largest intermediate parameter among the N(N-1)M intermediate parameters is stored in the set D as a data of the set D, and then the reactance XL of the u-th load at the first frequency point is given again. u (f1) Randomly assign a value within the assignment range (c1, c2), and store a data into the set D again according to the same method as above, until Q data are stored in the set D, where Q is the number of optimizations and is an integer greater than or equal to 500; at this time, take the data with the smallest value in the set D and record it as minD, and the reactance assignment of the S loads at the frequency point corresponding to minD is used as the reactance value corresponding to each load finally selected.

[0026] After executing the above steps, finally execute step (13) to complete the determination of each load parameter.

[0027] In order to verify the performance of the high-freedom multi-antenna structure with decoupling function of the present invention, let m=15, n=11, the rectangular metal patch adopts a square patch with a length and width of l, l=1.5mm, the spacing between two adjacent rectangular metal patches is d=0.3mm, N=2, that is, the high-freedom multi-antenna structure with decoupling function of the present invention includes two antennas, which are called antenna 1 and antenna 2 from left to right, respectively, wherein antenna 1 is formed by selecting the rectangular metal patches located in the 1st to 15th rows in the 4th column of rectangular metal patches, and then closing the switches between any two adjacent rectangular metal patches, and antenna 2 is formed by selecting the rectangular metal patches located in the 4th to 15th rows in the 8th column of rectangular metal patches, and then closing the switches between any two adjacent rectangular metal patches. Antenna 1 and antenna 2 are a pair of monopole antennas, which are used as a verification example of a high-degree-of-freedom multi-antenna structure with a decoupling function of the present invention. Six frequency points of 3.0 GHz, 3.5 GHz, 4.0 GHz, 4.5 GHz, 5.0 GHz and 5.5 GHz are selected to verify the decoupling of the antenna structure under a single frequency condition. The S parameters of the antenna structure are shown in FIG. Figure 3 Analysis Figure 3 It can be seen that the transmission coefficients at 3.0 GHz, 3.5 GHz, 4.0 GHz, 4.5 GHz, 5.0 GHz and 5.5 GHz are Both are greater than -10dB, indicating that the coupling between the two antennas is quite significant. Therefore, this verification example is used to verify the decoupling of dual antennas in a single frequency situation.

[0028] In order to achieve decoupling of antenna 1 and antenna 2, a decoupling structure is built for antenna 1 and antenna 2, as shown in Figure 2(a) and Figure 2(b), k1, k2, k3, and k4 are switches respectively. For antenna 1, the rectangular metal patches located in the 9th to 14th rows in the 1st column of rectangular metal patches are selected, and the switches between any two adjacent rectangular metal patches are closed, and the decoupling branch 6 is built. The decoupling branch 6 is a self-decoupling branch; the rectangular metal patches located in the 9th to 13th rows in the 3rd column of rectangular metal patches are selected. Except for the switch k2 between the rectangular metal patch in the 9th row and the rectangular metal patch in the 10th row, the switches between any other two adjacent rectangular metal patches are closed, and the decoupling branch 7 is built. The decoupling branch 7 is a parasitic decoupling branch. For antenna 2, select the rectangular metal patches located in the 11th row to the 14th row in the 11th column, close the switches between any two adjacent rectangular metal patches, and complete the construction of decoupling branch 8, which is a self-decoupling branch; select the rectangular metal patches located in the 11th row to the 13th row in the 9th column, except for the switch k3 between the rectangular metal patch in the 11th row and the rectangular metal patch in the 12th row, close the switches between any two other adjacent rectangular metal patches, and complete the construction of decoupling branch 9, which is a parasitic decoupling branch. Therefore, after the decoupling branches are built for antenna 1 and antenna 2, k1 and k4 are closed, and k2 and k3 are disconnected.

[0029] The required decoupling frequency is 3.5 GHz, and the load parameters of each decoupling branch are calculated as Y L(1) =7.2nH, Y L(2) =3.7nH, Y L(3) =1.6nH, Y L(4) =7.2nH.

[0030] The S parameter diagram of antenna 1 and antenna 2 after building a decoupling structure at a single frequency point of 3.5GHz is shown in the figure below. Figure 4 Analysis Figure 4 It can be seen that the decoupling frequency point obtained by actual simulation is f1 = 3.49 GHz. This decoupling frequency point offset is within the normal frequency deviation range. At this time, the transmission coefficient of antenna 1 and antenna 2 after decoupling is Less than -10dB, and compared to Figure 3 The S parameters and reflection coefficient of the original antenna structure of the verification example composed of antenna 1 and antenna 2 shown in the figure have been improved by more than 25dB, and the decoupling effect is significant.

[0031] In summary, the design and optimization of the high-freedom multi-antenna structure with decoupling function of the present invention can be achieved through a rectangular metal patch array, and the degree of freedom of design and optimization is high, which can achieve flexible expansion.

Claims

1. A high degree of freedom multi-antenna structure with decoupling function, characterized in that The invention comprises a rectangular metal patch array, wherein the rectangular metal patch array is formed by m*n rectangular metal patches of the same size being evenly spaced in m rows and n columns, wherein * represents a multiplication symbol, m and n are both integers, and m>5, n>4, and each two adjacent rectangular metal patches in each row and each two adjacent rectangular metal patches in each column are connected by a switch, and in an initial state, all switches are in an off state, and the number of antennas included in the high-freedom multi-antenna structure is recorded as N, and N is an integer greater than or equal to 2, and N columns of rectangular metal patches are selected from the rectangular metal patch array as N antenna building columns, and a required number of rectangular metal patches are selected from each antenna building column, and a switch between any two adjacent rectangular metal patches in the selected required number of rectangular metal patches is closed to build an antenna, thereby forming N antennas, and after forming the N antennas, a decoupling structure is built in the rectangular metal patches in other columns except the N antenna building columns in the rectangular metal patch array, and the decoupling structure enables the mutual admittance of any two antennas at each working frequency point to meet the design requirements.

2. According to claim 1, a high-freedom multi-antenna structure with a decoupling function further comprises a dielectric substrate, a first metal ground, a second metal ground and a plurality of metallized through holes, wherein the dielectric substrate is a rectangular parallelepiped structure, with the length direction of the dielectric substrate as the front-to-back direction, the width direction as the left-to-right direction, and the height direction as the up-down direction; the first metal ground is a rectangular structure, with the length direction of the first metal ground along the left-to-right direction, and the width direction along the front-to-back direction, the first metal ground attached to the upper surface of the dielectric substrate, the front end of the first metal ground flush with the front end surface of the dielectric substrate, the left end of the first metal ground flush with the left end surface of the dielectric substrate, and the right end of the first metal ground flush with the The right end surface of the dielectric substrate is flush, the width of the first metal ground is smaller than the length of the dielectric substrate, the second metal ground is a rectangular structure, the length direction of the second metal ground is along the left-right direction, and the width direction is along the front-back direction, the second metal ground is attached to the lower surface of the dielectric substrate, the front end of the second metal ground is flush with the front end surface of the dielectric substrate, the left end of the second metal ground is flush with the left end surface of the dielectric substrate, the right end of the second metal ground is flush with the right end surface of the dielectric substrate, and the width of the second metal ground is greater than the width of the first metal ground; a plurality of metallized through holes penetrate the first metal ground, the dielectric substrate and the second metal ground from top to bottom, and the first The metal ground is connected to the second metal ground, so that the first metal ground and the second metal ground become equipotential bodies; the plane that makes the dielectric substrate bilaterally symmetrical is called the first symmetry plane, m*n rectangular metal patches are attached to the upper surface of the dielectric substrate, the length direction of each rectangular metal patch is along the left-right direction, the width direction is along the front-back direction, the spacing between two adjacent rectangular metal patches in each row and the spacing between two rectangular metal patches in each column are equal, and the spacing is recorded as d, the front ends of the rectangular metal patches in each row are located in the same straight line, and the straight line is parallel to the front end surface of the dielectric substrate, the left ends of the rectangular metal patches in each column are located in the same straight line, and the straight line is parallel to the left end surface of the dielectric substrate, and the m The rows of rectangular metal patches are called the 1st row of rectangular metal patches to the mth row of rectangular metal patches from back to front, and the nth columns of rectangular metal patches are called the 1st column of rectangular metal patches to the nth column of rectangular metal patches from left to right. The straight line where the rear end of the 1st row of rectangular metal patches is located is located in front of the rear end of the dielectric substrate, and the straight line where the front end of the mth row of rectangular metal patches is located is located on the rear side of the rear end of the first metal ground, and the spacing between the two is d. The straight line where the left end of the first column of rectangular metal patches is located is located on the right side of the plane where the left end face of the dielectric substrate is located; the straight line where the right end of the nth column of rectangular metal patches is located is located on the left side of the plane where the right end face of the dielectric substrate is located, and the rectangular metal patch array is bilaterally symmetrical about the first symmetry plane.

3. A high degree of freedom multi-antenna structure with decoupling function according to claim 2, characterized in that Each antenna is constructed in the following manner: first, a column of rectangular metal patches in the rectangular metal patch array is selected, and a corresponding number of rectangular metal patches are selected from the mth row of rectangular metal patches in the column of rectangular metal patches, and then switches between any two adjacent rectangular metal patches in all the selected rectangular metal patches are closed. At this time, an antenna is constructed, wherein any two antennas select rectangular metal patches in different columns, N antennas are evenly spaced, and there are at least 3 columns of rectangular metal patches between two adjacent antennas; If a certain antenna is to operate at a single frequency, when the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the mth row is greater than half the wavelength of the operating frequency, in the antenna, the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the last row is closest to half the wavelength of the required operating frequency, and when the distance between the front end of the rectangular metal patch in the first row and the rear end of the rectangular metal patch in the mth row is less than or equal to half the wavelength of the operating frequency, the antenna selects the entire column of rectangular metal patches; If an antenna is to operate at multiple frequency points, when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is greater than the average value of 1 / 2 wavelength of its multiple operating frequencies, in the antenna, the distance between the front end of the rectangular metal patch in the first row and the back end of the rectangular metal patch in the last row is closest to the average value of 1 / 2 wavelength of its multiple operating frequencies, and when the distance between the front end of the rectangular metal patch in the 1st row and the back end of the rectangular metal patch in the mth row is less than or equal to the average value of 1 / 2 wavelength of its multiple operating frequencies, the antenna selects the entire column of rectangular metal patches.

4. A high degree of freedom multi-antenna structure with decoupling function according to claim 3, characterized in that The number of working frequencies of N antennas is recorded as M, and the N antennas are called the 1st antenna to the Nth antenna in order from left to right. The jth antenna needs to be built including K j The decoupling unit of the decoupling branch, K j is an integer greater than or equal to M(N-1), j=1,2,3,…,N; the decoupling units of N antennas constitute the decoupling structure, and the number of decoupling branches included in the decoupling structure is recorded as S, and S is an integer greater than or equal to MN(N-1); for the i-th antenna, i=2,3,…,N-1, the construction area of ​​its decoupling branch is located between the leftmost decoupling branch among all decoupling branches of the antenna and the i+1-th antenna, or between the rightmost decoupling branch among all decoupling branches of the antenna and the i-1-th antenna; for the first antenna, if the antenna is built at the first column of rectangular metal patches, the construction area of ​​its decoupling branch is between the antenna and the second antenna. If the antenna is not built at the first column of rectangular metal patches, the construction area of ​​the decoupling branch is between the leftmost decoupling branches of the antenna and the second antenna, or on the left side of the antenna; for the Nth antenna, if the antenna is built at the nth column of rectangular metal patches, the construction area of ​​the decoupling branch is between the rightmost decoupling branches of the antenna and the N-1th antenna, and if the antenna is not built at the nth column of rectangular metal patches, the construction area of ​​the decoupling branch is between the rightmost decoupling branches of the antenna and the N-1th antenna, or on the right side of the antenna; The decoupling unit of any one of the N antennas is constructed in the following manner: the number of rectangular metal patches used to construct the antenna is recorded as a, and any column of rectangular metal patches without other decoupling branches is selected in the construction area of ​​the antenna, and at least 3 rectangular metal patches are selected from the rectangular metal patch in the b-th row of the column of rectangular metal patches, and then, among all the selected rectangular metal patches, except for the switch between the rectangular metal patch in the b-th row and the rectangular metal patch in the b+1th row, the switches between any other two adjacent rectangular metal patches are closed, and a decoupling branch is constructed. The decoupling branch is called a parasitic decoupling branch, or Among all the selected rectangular metal patches, the switches between any two adjacent rectangular metal patches are closed, and a decoupling branch is built. This decoupling branch is called a self-decoupling branch, wherein if a is an odd number, then either b=ma / 2+1 / 2, or b=ma / 2-1 / 2, or b=ma / 2+3 / 2; if a is an even number, then either b=ma / 2+1, or b=ma / 2, or b=ma / 2+2; when all the decoupling branches of the antenna are built, all the decoupling branches of the antenna are connected according to the following connection method: the column number of the antenna in the rectangular metal patch array is denoted as g, that is, the column number of the antenna in the rectangular metal patch array is g. The antenna is constructed at the g-th column rectangular metal patch of the patch array, and the column number of the decoupling branch of the antenna located on the far left in the rectangular metal patch array is recorded as k, that is, the decoupling branch of the antenna located on the far left is constructed at the k-th column rectangular metal patch of the rectangular metal patch array, and the column number of the decoupling branch of the antenna located on the far right in the rectangular metal patch array is recorded as h, that is, the decoupling branch of the antenna located on the far right is constructed at the h-th column rectangular metal patch of the rectangular metal patch array. If the decoupling branches of the antenna are distributed on its left and right sides, then the h-th column located in the b-th row rectangular metal patch of the rectangular metal patch array is constructed at the k-th column to the h-th column. Among the k+1 rectangular metal patches, the switches between every two adjacent rectangular metal patches are closed. If the decoupling branches of the antenna are only distributed on its left side, the switches between every two adjacent rectangular metal patches in the g-k+1 rectangular metal patches located in the k-th column to the g-th column in the b-th row of the rectangular metal patch array are closed. If the decoupling branches of the antenna are only distributed on its right side, the switches between every two adjacent rectangular metal patches in the h-g+1 rectangular metal patches located in the g-th column to the h-th column in the b-th row of the rectangular metal patch array are closed. At this time, the connection of all the decoupling branches of the antenna is completed;After all the decoupling branches of the antenna are connected, in the construction area of ​​the antenna, at least one rectangular metal patch that is not used to build its decoupling branch is selected from the rectangular metal patch in the mth row to the rectangular metal patch in the m-2th row of the rectangular metal patch array as the grounding metal patch of the antenna, and each grounding metal patch of the antenna is provided with a metallized through hole that penetrates the grounding metal patch, the dielectric substrate and the second metal ground from top to bottom. The rectangular metal patch located in the front row of each decoupling branch of the antenna selects a connection path that can connect it to a grounding metal patch closest to it in a straight line distance, and the switch between any two adjacent rectangular metal patches on the connection path is closed, thereby realizing the connection between each decoupling branch of the antenna and the second metal ground, wherein, when there are multiple grounding metal patches with the closest straight line distance, one of the grounding metal patches is randomly selected, and the connection path selects a connection path that uses the least rectangular metal patches, and the connection path Any rectangular metal patch on the antenna cannot appear on the connection path between other decoupling branches of the antenna and the grounding metal patch. When there are multiple connection paths that meet the conditions and use the least rectangular metal patches, select any one of them; determine whether the switch between each grounding metal patch and its front, rear, left, and right adjacent rectangular metal patches is closed. If a switch is closed, a load is connected to both ends of the switch in parallel. At this time, the decoupling unit of the antenna is completed; when the decoupling units of N antennas are completed, the decoupling structure is formed. Since each decoupling branch must be connected to a grounding metal patch through a connection path, and there is no duplication of rectangular metal patches in the connection path between any decoupling branch and the grounding metal patch, there are a total of S decoupling branches, and each decoupling branch has a different connection path with the grounding metal patch and includes a load, so there are a total of S loads. After the S loads and load parameters are selected, the mutual admittance of any two antennas at each operating frequency can meet the design requirements. ; 5. A high degree of freedom multi-antenna structure with decoupling function according to claim 4, characterized in that Each of the loads is selected from one of capacitance and inductance. When the load is capacitance, the load parameter is the capacitance value. When the load is inductance, the load parameter is the inductance value. Any two loads and load parameters can be the same or different.

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