A broadband power divider based on metamaterial cells

Abstract

The application discloses a kind of broadband power dividers based on super material unit, it is related to power divider technical field, including coupling microstrip line and rectangular dielectric substrate, wherein coupling microstrip line is T-shaped distribution on dielectric substrate, it is characterized in that, further include multiple cross square super material units;The dielectric substrate is equipped with power division input interface, first power division output interface and second power division output interface;The super material unit is symmetrically distributed in the left and right sides of coupling microstrip line;The dielectric substrate is equipped with power division input interface, first power division output interface and second power division output interface and is respectively connected with the three end portions of the T-shaped coupling microstrip line.This application is on the basis of guaranteeing the working bandwidth of power divider, by adding super material to the miniaturization design of broadband power divider, with the advantages and beneficial effects of reducing the volume of power divider, reducing transmission line loss.

Description

Technical Field

[0001] This invention relates to the field of power divider technology, and more specifically to a broadband power divider based on metamaterial units. Background Technology

[0002] Power dividers, as key passive components in multi-port microwave systems, are crucial parts of the radio frequency (RF) front-end and are widely used in array antenna feed networks for wireless communication and satellite navigation systems, as well as in power combining for RF power amplifiers. To meet the demands of miniaturized feed networks for current multi-frequency array antennas, designing a power divider that can operate at multiple frequencies, has a wide bandwidth, small size, and low loss is particularly important. Commonly used traditional power dividers possess good amplitude and phase characteristics and isolation, and are simple to design, making them frequently used components in microwave circuit design. However, traditional power dividers can only operate at a single frequency and its odd harmonics, resulting in narrow bandwidth at lower frequencies. This makes it difficult to meet the dual-band wideband requirements of communication systems. Achieving dual-band wideband operation typically requires increasing the number of microstrip line segments, leading to a larger overall structure size and increased transmission line loss. Therefore, there is a need in the current technology for a small-sized, wide-bandwidth, and low-loss power divider. Summary of the Invention

[0003] This invention provides a broadband power divider based on metamaterial units, which solves the problem in the prior art that it is difficult to improve the narrow operating bandwidth of traditional power dividers in the low-frequency band without increasing the antenna size.

[0004] This invention is achieved through the following technical solution:

[0005] A broadband power divider based on metamaterial units includes coupled microstrip lines and a rectangular dielectric substrate, wherein the coupled microstrip lines are distributed in a T-shape on the dielectric substrate. The invention is characterized by further including multiple cross-shaped metamaterial units. The dielectric substrate is provided with a power divider input interface, a first power divider output interface, and a second power divider output interface. The metamaterial units are symmetrically distributed on the left and right sides of the coupled microstrip lines. The dielectric substrate is provided with a power divider input interface, a first power divider output interface, and a second power divider output interface, which are respectively connected to the three ends of the T-shaped coupled microstrip lines. Traditional power dividers can only operate on a single frequency and its odd harmonics, resulting in narrow bandwidth at lower frequencies. This makes it difficult to meet the dual-band broadband requirements of communication systems. Achieving dual-band broadband operation usually requires increasing the number of units, leading to a larger overall structural size and significantly increasing transmission line loss. Therefore, this invention provides a broadband power divider based on metamaterial units, solving the problem of narrow bandwidth in low-frequency operating bands of existing power dividers without increasing antenna size.

[0006] Specifically, a metamaterial unit is added to the power divider structure to enhance its operating bandwidth. During operation, a time-varying magnetic field is pre-programmed to periodically excite the power divider surface in a vertical manner. By adjusting the metal structure within the metamaterial unit, resonance is induced within the metamaterial unit, generating more induced current on the power divider surface and causing resonance with the metamaterial unit. This effectively increases the bandwidth of the power divider without increasing its size. When the time-varying magnetic field acts on the cross-shaped structure, it affects the current distribution within the structure. These currents flow within the metal structure, leading to changes in the electromagnetic response. This includes adjustments to inductive and capacitive effects caused by variations in the current distribution within the metal structure. Excitation with a time-varying magnetic field perpendicular to the power divider surface alters the electromagnetic field distribution on the surface. This further affects the power divider's performance, such as changing its frequency response characteristics. This can be used to achieve bandwidth broadening, allowing the power divider to operate over a wider frequency range.

[0007] Furthermore, the metamaterial unit includes a first metal unit and a second metal unit of different sizes; the coupled microstrip line includes a first strip segment, a second strip segment, a third strip segment and two fourth strip segments, and the power divider input interface, the first strip segment, the second strip segment and the third strip segment are connected end to end in sequence; one end of the two fourth strip segments is connected to the left and right sides of the third strip segment respectively, and the other end is connected to the first power divider output interface and the second power divider output interface respectively.

[0008] Furthermore, the second strip segment is U-shaped, and the third strip segment includes two parallel third strip segment sub-segments; one end of the first strip segment is connected to the power divider input interface, and the other end is connected to the sealed end of the second strip segment; one end of each of the two third strip segment sub-segments is connected to two ends of the open end of the second strip segment, and an internal gap is left between the two third strip segment sub-segments; one end of each of the two fourth strip segments is connected to the outer side of the other end of the two sub-segments, and the other end of each of the two fourth strip segments is connected to the first power divider output interface and the second power divider output interface, respectively; the first metal unit is disposed on the dielectric substrate on the left and right sides of the outer side of the second strip segment, and the second metal unit is disposed on the dielectric substrate on the left and right sides of the outer side of the two third strip segment sub-segments.

[0009] Furthermore, it also includes a first isolation resistor and a second isolation resistor; the first isolation resistor is connected to the internal gap at one end of the second strip segment opening, and the second isolation resistor is connected to the internal gap at the other end of the two third strip segments.

[0010] Furthermore, the first metal unit includes a rectangular first metal frame and a cross-shaped first cross piece. The first cross piece is centrally located within the first metal frame and is composed of two first metal strips of equal width but different lengths that are perpendicular to each other. The two ends of the longer first metal strip are connected to the first metal frame. A first metal notch is provided on one end of the first metal frame facing away from the power distribution input interface, which allows the interior of the first metal frame to communicate with the external space.

[0011] Furthermore, the second metal unit includes a rectangular second metal frame and a cross-shaped second cross piece. The second cross piece is centrally located within the second metal frame and is composed of two second metal strips of equal width but different lengths that are perpendicular to each other. The two ends of the longer second metal strip are connected to the second metal frame. The two ends of the second metal frame facing away from the power distribution input interface are provided with second metal notches, which allow the interior of the second metal frame to communicate with the external space.

[0012] Furthermore, the opening width of the first metal notch is equal to the opening width of the second metal notch; both the first metal frame and the second metal frame are squares, the side length of the first metal frame is greater than the side length of the second metal frame, and the thickness of the frame of the first metal frame is less than the thickness of the frame of the second metal frame; the width of the first metal strip and the width of the second metal strip are equal.

[0013] Compared with existing technologies, this invention miniaturizes the broadband power divider by adding metamaterials. By utilizing the resonant capability of the metamaterial unit when it is excited by a time-varying magnetic field, more induced current can be generated on the surface of the power divider and resonate with the metamaterial unit. This significantly improves the bandwidth of the power divider without increasing its size. While ensuring the working bandwidth of the power divider, it has the advantages and benefits of reducing the size of the power divider and reducing transmission line loss. Attached Figure Description

[0014] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0015] Figure 1 This is a schematic diagram of the power divider structure of the present invention;

[0016] Figure 2 This is a schematic diagram of the first metal unit structure of the present invention;

[0017] Figure 3 This is a schematic diagram of the second metal unit structure of the present invention;

[0018] Figure 4 This is a structural dimension diagram of the microstrip line and dielectric substrate in the power divider of the present invention;

[0019] Figure 5 This is a dimensional diagram of the first metal unit structure of the present invention;

[0020] Figure 6 This is a dimensional diagram of the second metal unit structure of the present invention;

[0021] Figure 7 This is a simulated value curve of the bandwidth of the power divider of the present invention;

[0022] Figure 8 This is a graph showing the measured bandwidth of the power divider of the present invention.

[0023] Figure 9 This is a graph showing the simulated isolation values ​​of the present invention.

[0024] Figure 10 This is a graph showing the isolation measurement values ​​of the present invention.

[0025] Figure 11 This is a comparison table of the size and bandwidth of power dividers in similar operating frequency bands in the embodiments of the present invention;

[0026] Figure 12 This is a comparison table of the working bandwidth of the power divider before and after loading the metamaterial unit in an embodiment of the present invention;

[0027] The attached diagram shows the markings and corresponding component names:

[0028] 1-First strip segment, 2-Second strip segment, 3-Third strip segment sub-segment, 4-Fourth strip segment, 5-First metal unit, 51-First metal frame, 52-First connecting piece, 53-First metal notch, 6-Second metal unit, 61-Second metal frame, 62-Second cross piece, 63-Second metal notch, 7-First isolation resistor, 71-Second isolation resistor, 8-Dielectric substrate. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0030] Example 1

[0031] like Figures 1-6As shown, this embodiment is a broadband power divider based on metamaterial units, including coupled microstrip lines and a rectangular dielectric substrate 8, wherein the coupled microstrip lines are distributed in a T-shape on the dielectric substrate 8. The device is characterized by further including a cross-shaped metamaterial unit, a first isolation resistor 7, and a second isolation resistor 71. The dielectric substrate 8 is provided with a power divider input interface, a first power divider output interface, and a second power divider output interface. The metamaterial unit includes a first metal unit 5 and a second metal unit 6 of different sizes. The coupled microstrip line includes a first segment 1, a second segment 2, a third segment, and a fourth segment 4, wherein the first segment 1 and the second segment 2 are one in number and the second segment 2 is U-shaped, the fourth segment 4 consists of two segments, and the third segment includes two parallel third segment sub-segments 3. One end of the first segment 1 is connected to the power divider... The input interface is connected, and the other end is connected to the sealed end of the second strip segment 2; one end of each of the two third strip segments 3 is connected to the two ends of the open end of the second strip segment 2, and there is an internal gap between the two third strip segments 3; one end of each of the two fourth strip segments 4 is connected to the outer side of the other end of the two third strip segments 3, and the other end of the two fourth strip segments 4 is connected to the first power divider output interface and the second power divider output interface respectively; the first metal unit 5 is disposed on the dielectric substrate 8 on the left and right sides of the second strip segment 2, and the second metal unit 6 is disposed on the dielectric substrate 8 on the left and right sides of the two third strip segments 3; the first isolation resistor 7 is connected to the internal gap at the open end of the second strip segment 2, and the second isolation resistor 71 is connected to the internal gap at the other end of the two third strip segments 3.

[0032] During the operation of the power divider, a time-varying magnetic field is first added to the working environment to act on the surface of the metamaterial unit. The cross-shaped structure typically includes intersecting sections made of metal or conductive material. When the time-varying magnetic field is perpendicular to these metal structures, it can cause current to flow inside the intersecting sections, generating an inductive effect. At the same time, the gaps between the first cross plate and the first metal frame 51, and between the second cross plate 62 and the second metal frame 61, can also generate a capacitive effect. The combination of these effects can cause the metamaterial unit to resonate at a specific frequency. This resonant frequency usually depends on the geometry, shape, and material properties of the metal structures of the first metal unit 5 and the second metal unit 6 in the metamaterial unit, as well as the frequency of the time-varying magnetic field. Near the resonant frequency, the inductive and capacitive effects induced by the time-varying magnetic field can significantly enhance the current in the metal structure. This enhanced current causes the electromagnetic response of the metal structure to become stronger at this frequency. At the same time, the effect of the time-varying magnetic field can modulate the electromagnetic response of the metamaterial unit, which means that the inductive and capacitive effects of the metamaterial unit may change under the influence of the time-varying magnetic field, thereby changing the overall electromagnetic properties of the metamaterial unit.

[0033] It should be noted that by segmenting the T-shaped coupled microstrip lines in the power divider, each segment can be configured with different electromagnetic characteristics. This allows for matching with the resonant frequency of the metamaterial unit, resulting in enhanced electromagnetic wave transmission or reflection within a specific frequency range. This enables the power divider to selectively distribute or reflect signals at certain frequencies, further improving its frequency and phase adjustment and selectivity. Simultaneously, the resonant interaction between the metamaterial unit and the segmented T-shaped microstrip lines can work together, enhancing induced current and electromagnetic response, thereby contributing to the bandwidth extension effect of the power divider. This allows the power divider to operate over a wider frequency range and improves its anti-interference performance. Dividing the metamaterial unit into first metal units 5 and second metal units 6 of different sizes can be used to adjust the frequency response characteristics of the microstrip lines. Larger metamaterial units may result in lower resonant frequencies, while smaller metamaterial units may result in higher resonant frequencies. This allows for control over the frequency response of the power divider.

[0034] More specifically, the second strip segment 2 is arranged in a U-shape, with the third strip segment 3 and the fourth strip segment 4 respectively positioned at both ends of the second strip segment 2. This is primarily used to provide a gap at the tail of the microstrip line when it is distributed in a T-shape. The gap is mainly used to adjust the resonant frequency of the T-shaped structure of the microstrip line. By adjusting the width of the gap and the parameters of the isolation resistor, the resonant frequency can be better controlled, matching or approaching the resonant frequency of the metamaterial unit to achieve better electromagnetic response. This helps ensure that different parts of the power divider can operate independently, thereby improving the performance of the power divider. The first isolation resistor 7 and the second isolation resistor 71 are mainly used to introduce electromagnetic isolation at the tail of the T-shaped microstrip line. This helps prevent mutual interference between different parts of the electromagnetic signal, especially between segments of the microstrip line. It also prevents electromagnetic signals from reflecting back to other parts at the tail of the T-shaped microstrip line, reducing reflection loss. Furthermore, the presence of the gap and the isolation resistor provides electromagnetic isolation between different parts, reducing electromagnetic coupling and crosstalk between microstrip lines. To better reduce the size of the power divider, in this embodiment, the tail gap of the microstrip line is centered and has a slender rectangular shape. In this embodiment, the specific positions of the first and second power divider output interfaces are not limited; since they are symmetrically arranged, their positions can be interchanged in specific implementations.

[0035] Furthermore, as a specific and limited implementation method, such as Figures 1-3As shown, the first metal unit 5 includes a rectangular first metal frame 51 and a cross-shaped first cross piece. The first cross piece is centrally located within the first metal frame 51 and is composed of two first metal strips of equal width but different lengths perpendicular to each other. The two ends of the longer first metal strip are connected to the first metal frame 51. A first metal notch 53 is provided at one end of the first metal frame 51 facing away from the power distribution input interface, allowing the interior of the first metal frame 51 to communicate with the external space. The second metal unit 6 includes a rectangular second metal frame 61 and a cross-shaped second cross piece 62. The second cross piece 62 is centrally located within the second metal frame 61 and is composed of two second metal strips of equal width but different lengths perpendicular to each other. The two ends of the longer second metal strip are connected to the second metal frame 61. Second metal notches 63 are provided at both ends of the second metal frame 61 facing away from the power distribution input interface, allowing the interior of the second metal frame 61 to communicate with the external space.

[0036] In this design, the central portion of both the first metal unit 5 and the second metal unit 6 is shaped like a cross, with the cross-shaped metal consisting of a longer metal strip and a shorter metal strip perpendicular to each other. The electromagnetic response of the cross-shaped structure can be influenced by adjusting its length and position. This adjustment can be used to tune the resonant frequency of the cross-shaped structure to match the desired frequency range. This helps achieve resonance effects at different frequencies, thereby improving the bandwidth extension performance of the power divider. The interaction between the resonant gap and the metal strips in the cross-shaped structure may lead to frequency-selective transmission or reflection, meaning that near the resonant frequency, electromagnetic waves may be enhanced or suppressed within the metamaterial unit, thus affecting the electromagnetic performance of the power divider. On the other hand, the configuration of the longer and shorter metal strips can be used to match the impedance between the metamaterial unit and its surrounding environment, which helps reduce reflection losses and ensures good signal transmission matching between the input and output interfaces of the power divider.

[0037] It should be noted that when using metamaterial units for bandwidth extension in power dividers, the working principle of these units involves their unique electromagnetic response characteristics. These characteristics do not directly depend on the properties of the constituent materials themselves, but rather on the constituent units, their geometry, and dimensions. Metamaterials are artificial electromagnetic materials that, through artificially designed structures, produce electromagnetic properties not found in natural materials. Their electromagnetic properties primarily depend on the structural dimensions of the periodic units, the periodic arrangement, and the inherent properties of the material. By adjusting these parameters, unique performance parameters not found in nature can be created, thereby enabling many novel electromagnetic functional devices. They have been widely applied in electronics, communications, and military fields. The emergence of metamaterials allows for the arbitrary design of the dielectric constant and permeability of materials according to requirements, enriching the diversity of material choices and realizing novel electromagnetic properties not found in traditional materials. Therefore, metamaterials have been used in the design and fabrication of various passive microwave devices. They can effectively reduce interference between different units of an array antenna, concentrate the antenna radiation beam and enhance radiation energy, and simplify the antenna structure. In the subwavelength band, they can adjust the amplitude, phase and polarization of electromagnetic waves, and achieve important radiation performance such as antenna element decoupling and gain enhancement, thus well meeting the needs of antenna miniaturization and decoupling of antenna devices.

[0038] In this embodiment, to improve the bandwidth of a traditional power divider, a metamaterial unit is added next to the microstrip line. When the power divider is operating, an induced current will appear on the cross-shaped structure, causing a change in the electromagnetic response within the structure. This response typically involves changes in current distribution and redistribution of the electromagnetic field, thereby altering the radiation performance of the entire power divider. This change in response can be controlled according to the design of the metamaterial to achieve the desired power dividing performance.

[0039] It should be noted that when using metamaterial units for bandwidth extension in power dividers, the working principle of the metamaterial units involves their response to electromagnetic waves, and this response is closely related to their structure and material properties. Metamaterials are artificially manufactured materials with electromagnetic properties different from natural materials. They are typically composed of tiny structural units that can be designed to produce special responses to electromagnetic waves of specific frequencies.

[0040] When a time-varying magnetic field is applied to the cross-shaped structure, it causes a change in the electromagnetic response within the structure. This response typically involves changes in current distribution and a redistribution of the electromagnetic field, leading to alterations in the reflection, transmission, and absorption of electromagnetic waves. This change in response can be controlled according to the design of the metamaterial to achieve the desired power-sharing performance, for example, through bandwidth broadening or phase control. When the added time-varying magnetic field acts on the cross-shaped structure of the first metal unit 5 and the second metal unit 6, it affects the current distribution within the structure. These currents flow within the metal structure, causing changes in the electromagnetic response; these effects are caused by changes in the current distribution within the metal structure. Simultaneously, the metal portion of the cross-shaped structure in the metamaterial unit can be considered as an inductive element; changes in the time-varying magnetic field will cause current to flow in the loops within the structure, generating an inductive effect.

[0041] Furthermore, in order to better satisfy the resonance and response between the power divider and the metamaterial unit to generate induced current, as a further defined implementation, the opening width of the first metal notch 53 is equal to the opening width of the second metal notch 63; both the first metal frame 51 and the second metal frame 61 are squares, the side length of the first metal frame 51 is greater than the side length of the second metal frame 61, and the thickness of the frame of the first metal frame 51 is less than the thickness of the frame of the second metal frame 61; the width of the first metal strip and the width of the second metal strip are equal.

[0042] In this design, both the first metal notch 53 and the second metal notch 63 are functionally resonant notches. Although the first metal unit 5 and the second metal unit 6 are different in size, providing them with resonant notches of the same opening size allows the first metal unit 5 and the second metal unit 6 to resonate at the same frequency, achieving frequency selective control. On the one hand, near this resonant frequency, the two block metal units can generate a resonant effect, enhancing or suppressing the propagation of electromagnetic waves at a specific frequency. On the other hand, even if the two block metal units resonate at the same resonant frequency, their size difference will still cause them to differ in the intensity and bandwidth of their resonant peaks. This means that the power divider can exhibit a resonant effect at multiple frequencies, thereby widening the bandwidth and enabling it to operate over a wider frequency range.

[0043] More specifically, both the first metal frame 51 and the second metal frame 61 are designed as squares because squares possess high symmetry, exhibiting high similarity and uniformity in electromagnetic response and current distribution across different directions, resulting in more stable performance compared to other rectangles under different directions and polarizations. The first metal frame 51 and the second metal frame 61 are respectively designed to be large and thin, and small and thick. These two metamaterial units typically have different resonant frequencies. The large and thin metal structure may have a higher resonant frequency, while the small and thick metal structure may have a lower resonant frequency. This allows the power divider to resonate within different frequency ranges, collectively covering a wider frequency range and thus widening the power divider's bandwidth. Simultaneously, the different electromagnetic response characteristics of the first metal unit 5 and the second metal unit 6 allow for more precise adjustment of the power divider's electromagnetic response.

[0044] Example 2

[0045] In this embodiment, to accurately represent the collaborative operation between the power divider and the metamaterial unit, and to reduce the size of a conventional power divider while maintaining sufficient operating bandwidth, such as Figures 4-6 As shown, the dielectric substrate 8 has a length of 48.6 mm, a width of 25.23 mm, a thickness of 1 mm, a relative dielectric parameter εr = 2.65, and is made of F4B material. The width of the first strip segment 1 and the fourth strip segment 4 is 2.72 mm, and the length is 10 mm. The length of the second strip segment 2 is 14.42 mm, the width of both ends of its opening is 1.58 mm, and the internal spacing is 1.02 mm. The length of the third strip segment 3 is 14.18 mm, the width is 2.04 mm, and when two third strip segments 3 are arranged parallel to each other at the two ends of the opening of the second strip segment 2, the internal spacing between the two third strip segments 3 is 1.05 mm. The first metal frame 51 is square, with a side length of 5.99 mm and a frame thickness of 0.29 mm, wherein the opening width of the first metal notch 53 is 0.46 mm. The first cross-shaped metal piece has a width of 0.6 mm, with the shorter piece having a length of 4.67 mm, and one end of the shorter piece facing the first metal notch 53. The second metal frame 61 is square, with a side length of 3.02 mm and a frame thickness of 0.36 mm, and the opening width of the second metal notch 63 is 0.46 mm. The second cross-shaped metal piece 62 has a width of 0.6 mm, with the shorter piece having a length of 1.82 mm, and two ends of the shorter piece facing the second metal notch 63. The first isolation resistor 7 has a resistance of 82 Ω, and the second isolation resistor 71 has a resistance of 270 Ω.

[0046] like Figures 7-10As shown, the operating frequency bands are 1.8~2.14 GHz and 4.73~5.58 GHz, respectively. Metamaterial units are then added to these bands. The dual operating frequency bands after adding the metamaterial units are adjusted to 1.82~2.47 GHz and 4.59~5.26 GHz. The power divider with the added metamaterial units consists of coupled microstrip lines, metamaterial metal units, and isolation resistors, and has one input port and two output ports. The planar structure is shown below. Figure 1 As shown. The selected dielectric substrate 8 is made of F4B material, with a length of 48.6 mm, a width of 25.23 mm, a thickness of 1 mm, and a relative permittivity εr = 2.65. Specific parameters of the two square-shaped open metamaterial metal units are as follows: Figure 2 As shown, the components are printed on both sides of the microstrip line of the power divider, sharing a dielectric substrate 8 with the power divider. In this embodiment, dual-frequency power dividers 1 and 2 without metamaterial units, having the same structure and similar operating frequency bands, are selected. This is compared to the dual-frequency power divider proposed in this embodiment (overall dimensions 26.31 × 52.2 mm). 2 For comparison, the overall dimensions of power divider 1 are 26.37 × 52.58 mm. 2 The overall dimensions of power divider 2 are 26.31 x 52.2 mm. 2 Bandwidth 1 is the low-frequency band bandwidth, and bandwidth 2 is the high-frequency band bandwidth. The comparison results are shown in Table 1. The results show that:

[0047] (1) Compared with the size of 1010 MHz total bandwidth, the overall size of the power divider in this embodiment is reduced to 88.4%, and the total bandwidth is increased by 180 MHz;

[0048] (2) Compared with the size of 1210 MHz total bandwidth, the overall size of the power divider in this embodiment is reduced to 89.3%, and the total bandwidth is increased by 40 MHz.

[0049] like Figures 11-12 As shown in Table 2, the working bandwidth of the power divider in this embodiment before and after loading the metamaterial unit is compared. The results show that after loading the metamaterial unit, the bandwidth of working band 1 is 650 MHz, the bandwidth of working band 2 is 670 MHz, and the average bandwidth is 660 MHz. The working bandwidth of the two bands is almost the same. The working band is shifted forward by 310 MHz to a lower frequency, and the total bandwidth increases by 130 MHz.

[0050] The comparison results show that, compared with the traditional dual-band power divider with a total bandwidth of 1010 MHz, the overall size of the power divider in this embodiment is reduced by 11.54%, and the total bandwidth is increased by 28.71%; compared with the traditional dual-band power divider with a total bandwidth of 1210 MHz, the overall size of the power divider in this embodiment is reduced by 10.71%, and the total bandwidth is increased by 13.04%. Furthermore, the performance of the metamaterial-based power divider fabricated in this embodiment is better than the simulation results by 0.12 GHz in the low-frequency band and lower than the simulation value by 0.06 GHz in the high-frequency band, thus verifying the present invention's use of metamaterials to improve the narrow low-frequency operating bandwidth of traditional dual-section dual-band power dividers. Figure 8 and Figure 9 As shown in the comparison, the measurement results of the effective frequency band of the proposed power divider isolation (S23>-20 dB) are compared with the simulation results. The measurement range of the effective frequency band of the power divider isolation can basically cover the simulation range, indicating that the power divider in this embodiment has good isolation when working normally.

[0051] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A broadband power divider based on metamaterial units, comprising coupled microstrip lines and a rectangular dielectric substrate (8), wherein the coupled microstrip lines are distributed in a T-shape on the dielectric substrate (8), characterized in that, It also includes multiple cross-shaped metamaterial units; the metamaterial units are symmetrically distributed on the left and right sides of the coupled microstrip line; the dielectric substrate (8) is provided with a power divider input interface, a first power divider output interface and a second power divider output interface and is respectively connected to the three ends of the T-shaped coupled microstrip line; The metamaterial unit includes a first metal unit (5) and a second metal unit (6) of different sizes; the coupled microstrip line includes a first strip segment (1), a second strip segment (2), a third strip segment and two fourth strip segments (4), the power divider input interface, the first strip segment (1), the second strip segment (2) and the third strip segment are connected end to end in sequence; one end of the two fourth strip segments (4) is connected to the left and right sides of the third strip segment respectively, and the other end is connected to the first power divider output interface and the second power divider output interface respectively.

2. A broadband power divider based on metamaterial units according to claim 1, characterized in that, The second strip segment (2) is U-shaped, and the third strip segment includes two parallel third strip sub-segments (3); one end of the first strip segment (1) is connected to the power divider input interface, and the other end is connected to the sealed end of the second strip segment (2); one end of the two third strip sub-segments (3) is respectively connected to the two ends of the opening end of the second strip segment (2), and there is an internal gap between the two third strip sub-segments (3); one end of the two fourth strip segments (4) is respectively connected to the outer side of the other end of the two third strip sub-segments (3), and the other end of the two fourth strip segments (4) is respectively connected to the first power divider output interface and the second power divider output interface; the first metal unit (5) is disposed on the dielectric substrate (8) on the left and right sides of the second strip segment (2), and the second metal unit (6) is disposed on the dielectric substrate (8) on the left and right sides of the two third strip sub-segments (3).

3. A broadband power divider based on metamaterial units according to claim 2, characterized in that, It also includes a first isolation resistor (7) and a second isolation resistor (71); the first isolation resistor (7) is connected to the internal gap at one end of the opening of the second strip segment (2), and the second isolation resistor (71) is connected to the internal gap at the other end of the two third strip segments (3).

4. A broadband power divider based on metamaterial units according to claim 1, characterized in that, The first metal unit (5) includes a rectangular first metal frame (51) and a cross-shaped first cross piece. The first cross piece is centrally located inside the first metal frame (51) and is composed of two first metal strips of equal width but different lengths perpendicular to each other. The two ends of the longer first metal strip are connected to the first metal frame (51). The first metal frame (51) has a first metal notch (53) at one end facing away from the power divider input interface. The first metal notch (53) allows the interior of the first metal frame (51) to communicate with the external space.

5. A broadband power divider based on metamaterial units according to claim 4, characterized in that, The second metal unit (6) includes a rectangular second metal frame (61) and a cross-shaped second cross piece (62). The second cross piece (62) is centrally located inside the second metal frame (61) and is composed of two second metal strips of equal width but different lengths perpendicular to each other. The two ends of the longer second metal strip are connected to the second metal frame (61). The two ends of the second metal frame (61) facing away from the power divider input interface are provided with second metal notches (63). The second metal notches (63) allow the interior of the second metal frame (61) to communicate with the external space.

6. A broadband power divider based on metamaterial units according to claim 4, characterized in that, The opening width of the first metal notch (53) is equal to the opening width of the second metal notch (63); both the first metal frame (51) and the second metal frame (61) are squares, the side length of the first metal frame (51) is greater than the side length of the second metal frame (61), and the thickness of the frame of the first metal frame (51) is less than the thickness of the frame of the second metal frame (61); the width of the first metal strip and the width of the second metal strip are equal.

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