Miniaturized ultra-wideband flexible antenna with equidifferent rectangular double-clip slot CPW feed

Abstract

The application discloses an equal-difference rectangular double-Clip slot CPW feed miniaturized ultra-wideband flexible antenna; the application solves the problems of the prior art, such as that the ultra-wideband antenna is difficult to consider miniaturization and wideband, the electric performance stability of the flexible antenna is insufficient in the bending state, the multi-resonance structure design mechanism is unclear, and the parameter controllability is poor, and the like. The radiation patch of the application is in the form of a trapezoidal structure with an equal-difference increment of side length, a double-resonance slot structure is arranged in the radiation patch, a multi-resonance coupling structure is formed by the combination of the trapezoidal radiation patch and the double-resonance slot structure, the coplanar waveguide feed structure is arranged in cooperation with the radiation patch and the ground structure to improve the impedance matching performance and expand the working bandwidth. The antenna has the advantages of simple structure, small size, good flexibility and wide working bandwidth, and can maintain stable electric performance under the conditions of straight state and small bending radius, and is suitable for wearable devices, flexible electronic systems and ultra-wideband wireless communication fields.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology and mainly relates to a miniaturized ultrawideband flexible antenna fed by equal-arithmetic rectangular double-Clip slot CPW. Background Technology

[0002] With the rapid development of wireless communication and flexible electronics technologies, ultra-wideband antennas have gained widespread attention in wearable communication devices, human body area networks (BNAs), short-range high-speed communication, and flexible electronic systems due to their advantages such as large bandwidth, high data transmission rate, and low system complexity. At the same time, these applications typically place multiple demands on antennas, including miniaturization, flexibility, and broadband capabilities.

[0003] Existing ultra-wideband antennas mostly employ planar monopole antennas, rectangular patch antennas, or extend their operating bandwidth by loading various slotted structures. However, while achieving ultra-wideband characteristics, these antennas often suffer from the following problems: On the one hand, in order to obtain a wider operating bandwidth, the antenna structure size is usually large, which makes it difficult to meet the engineering application requirements of miniaturized or electrically small antennas; On the other hand, as antenna size decreases, the impedance matching performance and radiation efficiency of the antenna tend to decrease significantly, resulting in limited operating bandwidth.

[0004] In addition, to meet the needs of flexible applications, some flexible antenna structures based on flexible dielectric materials have emerged in recent years. However, existing flexible antennas are prone to problems such as significant resonant frequency shift, increased impedance mismatch, or radiation pattern distortion when bent or deformed, resulting in insufficient electrical performance stability and making them difficult to adapt to practical flexible application environments.

[0005] In terms of bandwidth expansion, some existing technologies introduce multiple irregular gaps or parasitic structures on the radiating patch to excite multiple resonant modes. However, such structures usually rely on empirical design, the resonance mechanism is unclear, the parameter adjustment coupling is high, and it is difficult to achieve stable and controllable ultra-wideband performance while ensuring the miniaturization of the structure.

[0006] Therefore, how to achieve ultra-wideband operation through a clear and controllable multi-resonance mechanism while maintaining the miniaturization of the antenna structure, and how to maintain stable electrical performance under flexible bending conditions, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies and address issues such as the difficulty in balancing miniaturization and broadband performance in ultra-wideband antennas, insufficient electrical performance stability of flexible antennas under bending conditions, and unclear design mechanisms and poor parameter controllability of multi-resonance structures, this invention proposes a miniaturized ultra-wideband flexible antenna fed by an arithmetic rectangular dual-Clip slot CPW. The objective of this invention is to achieve ultra-wideband operation characteristics of the antenna while maintaining its miniaturized structure, through the construction of a clear and controllable multi-resonance mechanism; simultaneously, to improve the impedance matching stability and radiation performance of the antenna under flexible bending conditions, thereby meeting the application requirements of flexible electronics and broadband wireless communication systems.

[0008] A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW includes a flexible dielectric substrate, a radiating patch structure, and a coplanar waveguide feeding structure. The flexible dielectric substrate is rectangular; the radiating patch structure and the coplanar waveguide feeding structure are disposed on one side of the surface of the flexible dielectric substrate. The radial patch structure includes N rectangular patches; the N rectangular patches are sequentially spliced ​​along the extension direction of their short sides; the radial patch structure is symmetrical about the axis of symmetry of the flexible dielectric substrate parallel to the Y-axis; the lengths of the long sides of the N rectangular patches increase sequentially; the rectangular patch with the longest long side is the Nth rectangular patch; the rectangular patch with the shortest long side is the first rectangular patch. The coplanar waveguide feeding structure includes a left grounding conductor, a right grounding conductor, and a center feeder; A center feed line is provided on the outer side of the long side of the first rectangular patch; the center feed line is rectangular; the long side of the center feed line is parallel to the Y-axis; The short side of the rectangular patch is parallel to the power supply direction; the short sides of the N rectangular patches are all of equal length; the long side of the rectangular patch is perpendicular to the power supply direction. The long sides of the N rectangular patches satisfy: ; in, Let i be the length of the long side of the i-th rectangular patch; For length increments; The length of the first rectangular patch; Both the left and right grounding conductors are rectangular; they are symmetrically arranged about the axis of symmetry of the short side of the center feeder; a first gap is provided between the left grounding conductor and both the center feeder and the first rectangular patch; a second gap is provided between the right grounding conductor and both the center feeder and the first rectangular patch; the widths of the first and second gaps are both 0.05 mm to 0.5 mm; the center feeder is coplanar with both the left and right grounding conductors. The surface of the Nth rectangular patch is etched with a first resonant slot structure; the surface of the first rectangular patch is etched with a second resonant slot structure; both the first and second resonant slot structures are CLIP-type grooves; the bottom of the grooves of the first and second resonant slot structures are parallel to the x-axis; the CLIP-type groove is an improved U-shaped groove.

[0009] Furthermore, of the two side arms of the first resonant slot structure, the longer side arm is the first extended arm, and the shorter side arm is the first short arm; a first bent arm is provided at the end of the first short arm; the first bent arm is perpendicular to the first short arm; the length of the first extended arm is greater than the length of the first short arm; the distance between the outer wall of the slot bottom of the first resonant slot structure and the long side of the Nth rectangular patch is D_S1; the range of D_S1 is: 0mm. <D_S1<1mm。

[0010] Furthermore, of the two side arms of the second resonant slot structure, the longer side arm is the second extension arm, and the shorter side arm is the second short arm; a second bent arm is provided at the end of the second short arm; the second bent arm is perpendicular to the second short arm; the length of the second extension arm is greater than the length of the second short arm; the distance between the outer wall of the slot bottom of the second resonant slot structure and the long side of the first rectangular patch is D_S2; the range of D_S2 is 0 mm. <D_S2<1mm。

[0011] Furthermore, the range of N is [3, 8].

[0012] Furthermore, when N≥3, a resonant structure is provided on the Mth rectangular patch between the Nth rectangular patch and the first rectangular patch; the resonant structure is the same as the first resonant slot structure; the size of the resonant structure is a proportional reduction of the first resonant slot structure.

[0013] Furthermore, the range of M is [2, N-1].

[0014] Furthermore, the flexible dielectric substrate is made of a flexible dielectric material.

[0015] The beneficial effects of this invention are: by using a rectangular radiating patch structure with equal gradient changes to construct multiple equivalent current paths, multiple resonant modes are excited while keeping the overall size of the antenna small, thus achieving wideband coverage and effectively alleviating the technical contradiction between antenna miniaturization and broadband. This invention, through the rational design of the width of the arithmetic rectangular patch and the position and size of the resonant slots, allows for the adjustment of resonance at different frequency bands within the specified structural parameter range. This enables individual adjustment of the resonant characteristics at different frequency bands, resulting in a clear antenna resonance mechanism and controllable parameters, avoiding the uncertainties associated with empirical design. The various resonant slot structures located in the feed region and at the ends of the radiating patches effectively extend the antenna's operating bandwidth and improve its impedance matching performance across a wide frequency range by introducing equivalent inductance, capacitance effects, and disturbance current distribution. Based on a flexible thin-film dielectric substrate design, the antenna's resonant characteristics and radiation performance show minimal changes under bending or deformation, exhibiting excellent bending resistance and electrical performance stability, making it suitable for applications such as flexible electronics and wearable devices. The antenna employs a planar structure design, eliminating the need for complex multi-layer stacking or three-dimensional structures, facilitating manufacturing using printing, electroplating, or flexible circuitry processes, and possessing significant engineering practicality and promotional value. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the equal-gradient rectangular radiating patch structure of the antenna of the present invention; Figure 2 This is a schematic diagram of the overall structure of the antenna of the present invention after the resonant slot structure is loaded on the radiating patch; Figure 3 For corresponding Figure 1 The diagram shows the reflection coefficient S-parameter curve of the equal-gradient rectangular radiating patch antenna element. Figure 4 For corresponding Figure 2 The diagram shows the reflection coefficient S-parameter curve of the complete antenna element. Figure 5 This is a schematic diagram of the radiation pattern of the antenna of the present invention in the XOY and XOZ planes; Figure 6 This is a schematic diagram of the three-dimensional radiation pattern of the antenna of the present invention; Figure 7 This is a schematic diagram of the antenna's bent state structure according to the present invention; Figure 8 This is a schematic diagram of the antenna bending parameters of the present invention; Figure 9 This is a schematic diagram of the reflection coefficient S-parameter curves of the antenna of the present invention under different static bending states; Figure 10 This is a schematic diagram of the three-dimensional radiation pattern of the antenna of the present invention in a bent state; Wherein, L1 - length of the first rectangular patch; W1 - width of the first rectangular patch; L2 - length of the second rectangular patch; W2 - width of the second rectangular patch; L3 - length of the third rectangular patch; W3 - width of the third rectangular patch; L4 - length of the fourth rectangular patch; W4 - width of the fourth rectangular patch; Port_L - length of the center feeder; Port_W - width of the center feeder; GND_L - length of the right grounding conductor; GND_W - width of the right grounding conductor; D_L1 - length of the first short arm; D_L2 - length of the first extension arm; D_L3 - Length of the second short arm; D_L4 - Length of the second extension arm; D_W1 - Length of the outer edge of the CLIP-type slot bottom of the first resonant slot structure; D_W2 - Length of the first bent arm; D_W3 - Length of the outer edge of the CLIP-type slot bottom of the second resonant slot structure; D_W4 - Length of the second extension arm; D_S1 - Distance from the outer edge of the CLIP-type slot bottom of the first resonant slot structure to the long side of the nearest first rectangular patch; D_S2 - Distance from the outer edge of the CLIP-type slot bottom of the second resonant slot structure to the long side of the nearest rectangular patch; ZR - Antenna bending radius. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW includes a flexible dielectric substrate, a radiating patch structure, and a coplanar waveguide feeding structure. The flexible dielectric substrate is rectangular; the radiating patch structure and the coplanar waveguide feeding structure are disposed on one side of the surface of the flexible dielectric substrate. The plane containing one side surface of the flexible dielectric substrate is the XOY plane; the horizontal direction of the flexible dielectric substrate is the x-axis; within the XOY plane, the direction perpendicular to the x-axis is the y-axis; and the axis perpendicular to the XOY plane is the z-axis. In this invention, the "width" direction of the rectangular patch is defined as its long side direction, that is, W represents the length of the long side of the rectangular patch and L represents the length of the short side of the rectangular patch.

[0019] The radial patch structure includes N rectangular patches; the N rectangular patches are sequentially spliced ​​along the width extension direction of the rectangular patches; the short sides of the N rectangular patches are all of equal length; the long sides of the N rectangular patches increase sequentially; the radial patch structure is symmetrical about the axis of symmetry of the flexible dielectric substrate parallel to the Y-axis; the rectangular patch with the longest long side is the Nth rectangular patch; the rectangular patch with the shortest long side is the first rectangular patch; The radiating patch structure consists of multiple rectangular patches arranged sequentially along the feeding direction. The length of the rectangular patches increases in an incremental manner, thereby forming multiple current paths with different equivalent electrical lengths to excite multiple resonant modes and achieve coordinated radiation in different frequency bands. The coplanar waveguide feeding structure includes a left grounding conductor, a right grounding conductor, and a center feeder; A center feed line is provided on the outer side of the long side of the first rectangular patch; the center feed line is rectangular; the long side of the center feed line is parallel to the Y-axis; both the left and right grounding conductors are rectangular; the left and right grounding conductors are symmetrically arranged about the axis of symmetry of the short side of the center feed line; a first gap is provided between the left grounding conductor and both the center feed line and the first rectangular patch; a second gap is provided between the right grounding conductor and both the center feed line and the first rectangular patch; the width of the first gap and the width of the second gap are both in the range of 0.05 mm to 0.5 mm; the center feed line, the left grounding conductor, and the right grounding conductor are all arranged coplanarly to form a quasi-TEM transmission mode. The surface of the Nth rectangular patch is etched with a first resonant slot structure; the surface of the first rectangular patch is etched with a second resonant slot structure; both the first and second resonant slot structures are CLIP-type grooves. The bottom of the slot in both the first resonant slot structure and the bottom of the slot in the second resonant slot structure are parallel to the x-axis; In the first resonant slot structure, the longer side arm is the first extended arm, and the shorter side arm is the first short arm; a first bent arm is provided at the end of the first short arm; the first bent arm is perpendicular to the first short arm; the length of the first extended arm is greater than the length of the first short arm; the distance between the outer wall of the slot bottom of the first resonant slot structure and the long side of the Nth rectangular patch is D_S1; the range of D_S1 is: 0 <D_S1<1mm; In the second resonant slot structure, the longer side arm is the second extension arm, and the shorter side arm is the second short arm; a second bent arm is provided at the end of the second short arm; the second bent arm is perpendicular to the second short arm; the length of the second extension arm is greater than the length of the second short arm; the distance between the outer wall of the slot bottom of the second resonant slot structure and the long side of the first rectangular patch is D_S2; the range of D_S2 is: 0 <D_S2<1mm; The first and second resonant slot structures are used to regulate the impedance characteristics and resonant modes of the antenna. Specifically, the second resonant slot structure is located at the edge region of the center feed line to improve impedance matching characteristics in the mid-to-low frequency band; the first resonant slot structure is located in the rectangular patch region with the largest side length to disturb the current distribution at the patch edge and excite higher-order resonant modes, thereby further extending the antenna's operating bandwidth. The range of N is [3, 8]; A resonant structure is provided on the Mth rectangular patch between the Nth rectangular patch and the first rectangular patch; the resonant structure is the same as the first resonant slot structure; the size of the resonant structure is a proportional reduction of the size of the first resonant slot structure; where M ranges from [2, N-1]. The flexible dielectric substrate is made of flexible dielectric material, which enables the antenna to maintain stable impedance matching performance and radiation performance even when bent.

[0020] In use, simply connect the central feed line of this invention using an SMA connector, or directly etch the structure of this invention onto the circuit board. Connecting the feed port to the functional circuit enables the reception and transmission of electromagnetic waves. This invention is applicable to related technical fields such as flexible electronic systems, wearable devices, and broadband wireless communication, including devices such as wearable watches, VR glasses, electronic rings, and locators.

[0021] The antenna unit substrate measures 10 mm × 10 mm × 0.125 mm, i.e., Sub_L = 10 mm, Sub_W = 10 mm, Sub_H = 0.125 mm. Polyimide (PI) is used as the dielectric material, with a relative permittivity of 3.5 and a loss tangent of 0.002. It exhibits high-frequency stability and mechanical flexibility. All metal planar structures above the dielectric substrate are copper-plated, with a metal planar thickness of 0.035 mm.

[0022] The antenna element uses CPW feeding, with the center conductor and the two side grounding conductors arranged in the same plane. A quasi-TEM mode is formed between the center conductor and the two side grounding plates. The electric field is mainly distributed at the air-dielectric interface, and the magnetic field is a closed ring magnetic field surrounding the center conductor.

[0023] The unit structure is shown in Figure 1. The Z-axis is perpendicular to the XOY plane and pointing upwards. The CPW feed line has a width of Port_W and a length of Port_L. The coplanar ground has a width of GND_W and a length of GND_L. The feed line and the coplanar ground are symmetrical about the central axis of the dielectric substrate. The left coplanar ground is aligned with the left and lower edges of the dielectric substrate, and the right coplanar ground is aligned with the right and lower edges of the dielectric substrate. The lower edge of the feed line is aligned with the lower edge of the dielectric substrate. The upper edge of the feed line is connected to the radiating patch. The gap between the ground and the feed line is 0.1 mm, and the gap between the ground and the radiating patch is 0.1 mm. The radiating patch passes through a width gradient. The rectangular patch combination with equal arithmetic progressions, since the width direction of the rectangular patch in this invention is defined as its long side direction, the width variation actually corresponds to the change in the length of the patch's long side; by modulating the current path through patches of different lengths, multiple resonant modes are excited. The difference in width of each patch results in different equivalent electrical lengths, thereby covering a wider frequency band. Rectangular patches of different widths correspond to different equivalent current path lengths, thereby generating multiple adjacent resonant points in different frequency bands to broaden the overall impedance bandwidth. The optimized equal trapezoidal patch antenna unit structure parameters are shown in Table 1.

[0024] The radial patches are arranged in an inverted triangle, arranged in an arithmetic progression rectangle pattern, stacked from the feed line side towards the end of the dielectric substrate. The patches closest to the feed line are L1 and W1, extending sequentially towards the Y-axis as L2 and W2, L3 and W3, and L4 and W4. The arithmetic progression rectangles exhibit a geometric constraint relationship of L1=L2=L3=L4, and W1... <W2<W3<W4。

[0025] The S-parameters of the equal-gradient rectangular patch antenna element are shown in Figure 3. It can be seen that the antenna element has S11 < 1 in the 5.838–16.978 GHz frequency band. 10 dB, the absolute bandwidth of the antenna element is 11.14 GHz, and the relative bandwidth is 97.6%.

[0026] To further expand the bandwidth, two resonant slot structures are designed on the patch, as shown in Figure 2. One clip slot is located at the feed line end, and the equivalent inductance is adjusted by the slot length to form a parallel resonance with the feed line junction capacitance. The other clip slot is located at the edge of the radiating patch end, and a higher-order resonant mode is excited by perturbing the current at the patch end. The parameters of the two clip slots are shown in Table 1. The slot linewidth is 0.2 mm to ensure the continuity of high-frequency current and avoid performance degradation in the main frequency band.

[0027] Clip slots require the extension arm to be longer than the bending arm. In this invention, D_L2 is required to be greater than D_L1, D_L4 is required to be greater than D_L3, the Clip slot near the end of the feed line is not more than 1mm from the edge of the feed line, and the Clip slot near the end edge of the radiating patch is not more than 1mm from the end of the radiating patch. That is, there are hard geometric constraints D_S1<1mm, D_S2<1mm, and D_W1 and D_W3 are symmetrical about the center of the dielectric substrate.

[0028] After slotting, the S-parameters of the antenna element are shown in Figure 4. It can be seen that the S11 of the antenna element is < 5.569–18.669 GHz in the frequency band. The absolute bandwidth is 13.1 GHz, which is 1.96 GHz higher than the bandwidth before slotting, and its relative bandwidth becomes 108%.

[0029] The antenna element radiation pattern is shown in Figures 5 and 6. As can be seen from the radiation pattern, the antenna has an approximately omnidirectional radiation characteristic within the target operating frequency band.

[0030] The electrical dimension 'a' of the designed antenna element at the lowest operating frequency of 5.569 GHz is calculated as follows: (1) (2) It can be seen that the designed antenna element satisfies ESA a < 0.2 Engineering standards.

[0031] The flexibility of the antenna element was tested, as shown in Figures 7 and 8. The antenna element was bent, and the minimum bending radius typically needs to be greater than or equal to 5 times its thickness. Considering the properties of PI material, the minimum bending radius of the antenna element was taken as ZR = 5 mm. Under static conditions, the antenna element's S11 < 5 mm within the range of 5.637–18.256 GHz. With a resonant offset of 10 dB and a resonant offset rate of 1.42%, the antenna exhibits excellent flexibility and resistance to bending. The changes in the antenna's electrical performance caused by bending radii ranging from 5 mm to 10 mm were tested, as shown in Figures 9 and 10. It was found that the designed antenna element maintained stable electrical performance under bending conditions, and the radiation pattern did not undergo distortion.

[0032] Table 1. Optimized structural parameters of the isogradable rectangular patch antenna element

[0033] Appendix Figure 1This is a schematic diagram of the equal-gradient rectangular radiating patch structure of the antenna of the present invention. The radiating patch is disposed on one side of a flexible dielectric substrate, and its entirety is composed of multiple rectangular units arranged in an equal-gradient manner, with continuous transitions between adjacent rectangular units to form a gradually changing current distribution path for achieving multi-frequency resonance characteristics.

[0034] Appendix Figure 2 In order to be in Figure 1 The diagram shows the overall antenna structure after adding a resonant slot structure to the arithmetic rectangular radiating patch. The radiating patch contains dual clip-shaped resonant slots, which work in conjunction with the arithmetic rectangular radiating patch to adjust the antenna's equivalent electrical length and impedance characteristics, thus forming a multi-resonance operating mode.

[0035] Appendix Figure 3 For corresponding Figure 1 The diagram shows the reflection coefficient S-parameter curve of the equal-gradient rectangular radiating patch antenna element, which is used to characterize the impedance matching characteristics and operating frequency range of the equal-gradient rectangular radiating patch antenna without a resonant slot.

[0036] Appendix Figure 4 For corresponding Figure 2 The schematic diagram of the reflection coefficient S-parameter curve of the complete antenna element is shown, which is used to characterize the overall impedance matching characteristics and frequency response changes of the antenna after loading the resonant slot structure.

[0037] Appendix Figure 5 This is a schematic diagram of the radiation pattern of the antenna in the XOY and XOZ planes of the present invention, reflecting the radiation distribution characteristics of the antenna in different main cross sections.

[0038] Appendix Figure 6 This is a three-dimensional radiation pattern diagram of the antenna of the present invention, used to show the overall radiation distribution of the antenna in various directions in space.

[0039] Appendix Figure 7 This is a schematic diagram of the antenna of the present invention in a bent state. The flexible dielectric substrate is bent along a predetermined direction to simulate the use state of the antenna in a flexible application scenario.

[0040] Appendix Figure 8 This is a schematic diagram of the antenna bending parameters of the present invention, wherein the bending state of the antenna is characterized by the bending radius and related geometric parameters, which are used to describe the structural morphology under different bending conditions.

[0041] Appendix Figure 9 This is a schematic diagram of the reflection coefficient S-parameter curves of the antenna of the present invention under different static bending states, used to characterize the impedance matching changes of the antenna under different bending conditions.

[0042] Appendix Figure 10 This is a schematic diagram of the three-dimensional radiation pattern of the antenna of the present invention in a bent state, used to illustrate the spatial radiation distribution characteristics of the antenna under bending conditions.

[0043] Simulation results using CST Studio Suite demonstrate that the antenna of this invention exhibits S11 < 5.569–18.669 GHz. 10 dB, absolute bandwidth 13.1 GHz, relative bandwidth 108%, and unit electrical size of only 0.185 in the low-frequency band. It outperforms the electrically small antenna (ESA) by 0.2. According to engineering standards, the bending radius is 5mm in static conditions, and S11 < 5.637–18.256 GHz. With a 10 dB resonant offset of 1.42%, the electrical performance remained stable.

[0044] This invention integrates miniaturization, ultra-wideband, and flexible stability into one, and is simple to manufacture with extremely low cost.

[0045] Compared with other existing antennas, in terms of miniaturization, the antenna of this invention has a smaller electrical size than most common wearable antennas on the market. In terms of ultra-wideband, this invention breaks through 100% in relative bandwidth. In terms of flexible performance and stability, it can still ensure that the resonance does not shift significantly when the bending curvature is only 5mm. In terms of manufacturing, it only uses a single-layer design and can be manufactured by copper plating and etching processes, which is simple and convenient to produce and has extremely low cost.

[0046] In terms of antenna performance, compared with the listed comparative literature, the present invention exhibits better overall performance in terms of antenna electrical size, relative bandwidth and impedance stability under bending conditions. By comparing with similar antennas with better performance, it can be found that the present invention has superior miniaturization, ultra-wideband, flexible stability and electromagnetic mechanical robustness.

[0047]

[0048] Among them, [1] is P. Chen, D. Wang, and Z. Gan, “Flexible and small textile antenna for UWB wireless body area network,” Micromachines, vol. 14, no. 4, Art. no. 718, Apr. 2023; [2] is P. A. Pathak, S. L. Nalbalwar, A. E. Wagh et al., “A circular-shaped two-slot foam-based flexible UWB antenna for medical applications,” EURASIP J. Wireless Commun. Netw., vol. 2024, Art. no. 89, 2024; [3] is W. Yang, X. Zhao, Z. Guo et al., “A compact tri-notched flexible UWB antenna based on an inkjet-printable and plasma-activated silver nanoink,” Sci. Rep., vol. 14, Art. no. 11407, 2024; [4] is K. V. Karad and V. S. Hendre, “A flower bud-shaped flexible UWB antenna for healthcare applications,” EURASIP J. Wireless Commun. Netw., vol. 2023, Art. no. 27, 2023; [5] is A. Maria and P. Mythili, “Compact UWB wearable textile antenna for on-body WBAN applications,” Progress In Electromagnetics Research B, vol. 105, pp. 43–57, 2024。

Claims

1. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW, characterized in that: It includes a flexible dielectric substrate, a radiating patch structure, and a coplanar waveguide feeding structure; the flexible dielectric substrate is rectangular; the radiating patch structure and the coplanar waveguide feeding structure are disposed on one surface of the flexible dielectric substrate. The radial patch structure includes N rectangular patches; the N rectangular patches are sequentially spliced ​​along the extension direction of their short sides; the radial patch structure is symmetrical about the axis of symmetry of the flexible dielectric substrate parallel to the Y-axis; the lengths of the long sides of the N rectangular patches increase sequentially; the rectangular patch with the longest long side is the Nth rectangular patch; the rectangular patch with the shortest long side is the first rectangular patch. The coplanar waveguide feeding structure includes a left grounding conductor, a right grounding conductor, and a center feeder; A center feed line is provided on the outer side of the long side of the first rectangular patch; the center feed line is rectangular; the long side of the center feed line is parallel to the Y-axis; The short side of the rectangular patch is parallel to the power supply direction; the short sides of the N rectangular patches are all of equal length; the long side of the rectangular patch is perpendicular to the power supply direction. Both the left and right grounding conductors are rectangular; they are symmetrically arranged about the axis of symmetry of the short side of the center feeder; a first gap is provided between the left grounding conductor and both the center feeder and the first rectangular patch; a second gap is provided between the right grounding conductor and both the center feeder and the first rectangular patch; the widths of the first and second gaps are both 0.05 mm to 0.5 mm; the center feeder is coplanar with both the left and right grounding conductors. The surface of the Nth rectangular patch is etched with a first resonant slot structure; the surface of the first rectangular patch is etched with a second resonant slot structure; both the first and second resonant slot structures are Clip-type grooves.

2. The miniaturized ultrawideband flexible antenna with equal-arithmetic rectangular double-Clip slot CPW feeding according to claim 1, characterized in that, The long sides of the N rectangular patches satisfy: ； in, Let i be the length of the long side of the i-th rectangular patch; For length increments; The length of the first rectangular patch.

3. The miniaturized ultrawideband flexible antenna with equal-arithmetic rectangular double-Clip slot CPW feeding according to claim 1, characterized in that, The Clip-shaped groove is an improved U-shaped groove; the bottom of the groove of the first resonant slot structure is parallel to the x-axis; of the two side arms of the first resonant slot structure, the longer side arm is the first extension arm, and the shorter side arm is the first short arm; a first bent arm is provided at the end of the first short arm; the first bent arm is perpendicular to the first short arm; the length of the first extension arm is greater than the length of the first short arm; the distance between the outer wall of the groove bottom of the first resonant slot structure and the long side of the Nth rectangular patch is D_S1.

4. The miniaturized ultrawideband flexible antenna with equal-arithmetic rectangular double-Clip slot CPW feeding according to claim 1, characterized in that, The Clip-shaped groove is an improved U-shaped groove; the bottom of the groove of the second resonant slot structure is parallel to the x-axis; of the two side arms of the second resonant slot structure, the longer side arm is the second extension arm, and the shorter side arm is the second short arm; a second bent arm is provided at the end of the second short arm; the second bent arm is perpendicular to the second short arm; the length of the second extension arm is greater than the length of the second short arm; the distance between the outer wall of the groove bottom of the second resonant slot structure and the long side of the first rectangular patch is D_S2.

5. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW according to claim 1, characterized in that, When N≥3, a resonant structure is set on the Mth rectangular patch between the Nth rectangular patch and the first rectangular patch; the resonant structure is the same as the first resonant slot structure; the size of the resonant structure is a proportional reduction of the first resonant slot structure; the range of M is [2, N-1].

6. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW according to claim 1, characterized in that, The flexible dielectric substrate is made of flexible dielectric material.

7. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW according to claim 1, characterized in that, The range of N is [3, 8].

8. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW according to claim 3, characterized in that, The range of D_S1 is: 0mm <D_S1<1mm。 9. A miniaturized ultrawideband flexible antenna fed by an arithmetic rectangular double-Clip slot CPW according to claim 4, characterized in that, The range of D_S2 is: 0mm <D_S2<1mm。

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