Miniaturized planar ultra-wideband antenna and mobile terminal

Abstract

The utility model provides a miniaturized planar ultra-wideband antenna and a mobile terminal. The antenna comprises a radiation layer, a dielectric layer and a recessed ground layer which are stacked in sequence. The radiation layer comprises a trapezoidal radiation patch and a micro-strip feeder line; one end of the microstrip feeder line is connected with the upper bottom of the trapezoidal radiation patch; a T-shaped gap is formed in the sunken ground layer; and a vertical branch of the T-shaped slot corresponds to the trapezoidal radiation patch, and a transverse branch of the T-shaped slot is parallel to the microstrip feeder. The antenna provided by the utility model has the characteristics of miniaturization, high radiation efficiency and high gain, and the communication and positioning performance of the ultra-wideband antenna can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of antennas, in particular to a miniaturized planar ultra-wideband antenna and a mobile terminal. Background Art

[0002] With the rapid development of modern wireless communication positioning services, customers have higher and higher requirements for high transmission rates and high-precision positioning. In this context, ultra-wideband wireless communication and positioning systems have been proposed. As one of the key devices of ultra-wideband wireless communication and positioning systems, planar ultra-wideband filters have attracted the attention of industry engineers and scholars due to their advantages such as low profile, low cost, and easy connection with other RF devices. However, planar ultra-wideband filters in the prior art often have the defects of large size and low gain, which greatly limit their use in modern intelligent mobile terminals. Summary of the Utility Model

[0003] The technical problem to be solved by the utility model is to provide a miniaturized planar ultra-wideband antenna and a mobile terminal, which have the characteristics of miniaturization and high gain, can improve the performance of ultra-wideband wireless communication and positioning, and can be widely used in modern wireless mobile terminals.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is as follows:

[0005] The miniaturized planar ultra-wideband antenna includes a radiation layer, a dielectric layer, and a sunken ground layer stacked in sequence; the radiation layer includes a trapezoidal radiation patch and a microstrip feeder; one end of the microstrip feeder is connected to the upper base of the trapezoidal radiation patch; a T-shaped slot is formed in the sunken ground layer; the vertical branch of the T-shaped slot corresponds to the trapezoidal radiation patch, and the horizontal branch of the T-shaped slot is parallel to the microstrip feeder.

[0006] Optionally, the horizontal branch of the T-shaped slot is arranged at the edge position of the sunken ground layer.

[0007] Optionally, the other end of the microstrip feeder is connected to the edge position of the circuit board;

[0008] One end of the horizontal branch corresponding to the other end of the microstrip feeder extends to the edge position of the sunken ground layer, and the other end is spaced from the edge position of the sunken ground layer by a preset distance.

[0009] Optionally, the width of the horizontal branch of the T-shaped slot ranges from 2 to 3 mm; the width of the vertical branch of the T-shaped slot ranges from 12.0 to 14.0 mm, and the length ranges from 7.5 to 8.5 mm.

[0010] Optionally, the distance between the vertical branch and one end of the horizontal branch of the T-shaped slot ranges from 6 to 10 mm, and the distance between the vertical branch and the other end of the horizontal branch ranges from 3 to 5 mm.

[0011] Optionally, the upper base of the trapezoidal radiating patch ranges from 7.1 to 8.9 mm, the lower base ranges from 8 to 10 mm, and the height ranges from 7.5 to 8.5 mm.

[0012] Optionally, the length of the microstrip feeder ranges from 6 to 10 mm, and the width ranges from 1.5 to 1.6 mm.

[0013] Optionally, the distance between the lower base of the trapezoidal radiating patch and the edge of the corresponding radiation layer ranges from 6 to 10 mm; the distance between one end of the upper base of the trapezoidal radiating patch corresponding to the horizontal branch and the edge of the corresponding radiation layer ranges from 8 to 12 mm.

[0014] The second technical solution adopted by the present utility model is as follows:

[0015] A planar ultra-wideband filter, comprising the above-mentioned miniaturized planar ultra-wideband antenna.

[0016] The third technical solution adopted by the present utility model is as follows:

[0017] A mobile terminal, comprising the above-mentioned miniaturized planar ultra-wideband antenna.

[0018] The beneficial effects of the present utility model are as follows: The miniaturized planar ultra-wideband antenna of the present utility model has a radiation layer including a trapezoidal radiating patch and a microstrip feeder; the trapezoidal radiating patch can play a role in increasing the bandwidth and optimizing the matching; at the same time, its sunken ground layer is provided with a T-shaped slot, and the horizontal branch of the T-shaped slot corresponds to the trapezoidal radiating patch, which can not only further increase the optimization of the bandwidth matching, but also convert the directional antenna into an omnidirectional antenna. Therefore, the antenna of the present utility model has the advantages of miniaturization, ultra-wideband, high radiation efficiency, and high gain. Description of the Drawings

[0019] Figure 1 It is a hierarchical structure diagram of the miniaturized planar ultra-wideband antenna provided by an embodiment of the present invention;

[0020] Figure 2 It is a front view schematic diagram of the miniaturized planar ultra-wideband antenna provided by an embodiment of the present invention;

[0021] Figure 3 It is a back view schematic diagram of the miniaturized planar ultra-wideband antenna provided by an embodiment of the present invention;

[0022] Figure 4It is a comparison diagram of size parameters in the front view schematic diagram of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention;

[0023] Figure 5 It is a comparison diagram of size parameters in the rear view schematic diagram of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention;

[0024] Figure 6 It is a curve graph of the reflection coefficient change of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention with the parameter W S1 changing;

[0025] Figure 7 It is a curve graph of the reflection coefficient change of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention with the parameter W S2 changing;

[0026] Figure 8 It is a curve graph of the reflection coefficient change of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention with the parameter L S1 changing;

[0027] Figure 9 It is a curve graph of the reflection coefficient change of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention with the parameter L S2 changing;

[0028] Figure 10 It is a curve graph of the reflection coefficient change of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention with the parameter W RU changing;

[0029] Figure 11 It is a simulation result diagram of the reflection coefficient of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention when using optimized parameters;

[0030] Figure 12 It is the radiation pattern of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention at 3.8 GHz when using optimized parameters;

[0031] Figure 13 It is the radiation pattern of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention at 6.8 GHz when using optimized parameters;

[0032] Figure 14 It is the radiation pattern of the miniaturized planar ultra-wideband antenna provided by the embodiment of the present invention at 9.8 GHz when using optimized parameters.

[0033] Label description:

[0034] 1. Radiation layer; 2. Dielectric layer; 3. Defective ground layer;

[0035] 11. Trapezoidal radiation patch; 12. Microstrip feeder;

[0036] 31. T-shaped slot; 32. vertical branch; 33. horizontal branch. Detailed implementation manners

[0037] To describe in detail the technical content, achieved objectives and effects of the present utility model, the following is described in conjunction with the implementation manners and with reference to the drawings.

[0038] Please refer to Figures 1 to 3 , Embodiment 1 of the present utility model is as follows:

[0039] This embodiment provides a miniaturized planar ultra-wideband antenna. As Figure 1 shown, it includes a radiation layer 1, a dielectric layer 2 and a defective ground layer 3 with a stacked structure. Among them, the radiation layer 1 is mounted on the upper surface of the dielectric layer 2, and the defective ground layer 3 is mounted on the lower surface of the dielectric layer 2. The radiation layer 1 and the defective ground layer 3 are made of metal materials.

[0040] As Figure 2 shown, the radiation layer 1 includes a trapezoidal radiation patch 11 and a microstrip feeder 12. One end of the microstrip feeder 12 is connected to the upper base of the trapezoidal radiation patch 11, and the other end (i.e., the feeding end) is connected to the edge position of the dielectric layer 2. Here, setting the radiation patch as trapezoidal can play a role in increasing the bandwidth and optimizing the matching.

[0041] In some specific implementation manners, as Figure 2 shown, the microstrip feeder 12 is located at the center point position of the edge of the radiation layer 1, and the trapezoidal radiation patch 11 connected thereto is located near the center point position of the radiation layer.

[0042] In a preferred example, combining Figure 2 and Figure 3 it can be known that the upper base of the trapezoidal radiation patch 11 takes the microstrip feeder 12 as the center line, and the length of the side corresponding to the T-shaped slot 31 on the defective ground layer 3 is less than the length of the other side. That is to say, the microstrip feeder 12 is not located at the center point position of the upper base, but is closer to the T-shaped slot 31 on the defective ground layer.

[0043] In this embodiment, the layout design of the radiation layer can effectively optimize the surface circuit distribution on the radiation patch to achieve high gain, and introduce the multi-mode concept to increase the band to achieve ultra-wideband characteristics. Therefore, based on the radiation layer layout design of this embodiment, the antenna characteristics of ultra-wideband and high gain can be shown.

[0044] As Figure 3As shown, a T-shaped slot 31 is provided on the sunken ground layer 3 of this embodiment; the T-shaped slot 31 is formed by a vertical branch 32 and a horizontal branch 33 which are perpendicularly arranged. Among them, the vertical branch 32 corresponds to the trapezoidal radiation patch 11. That is to say, the two correspond (there is a large part of overlap) in the hierarchical structure.

[0045] In some specific embodiments, in combination with Figure 2 and Figure 3 it can be known that the horizontal branch 33 in the sunken ground layer 3 is parallel to the microstrip feeder 12 in the radiation layer 1. Preferably, the horizontal branch 33 is located at the edge position of the sunken ground layer 3. Preferably, one end of the horizontal branch 33 extends to connect to the edge position of the sunken ground layer 3, and the other end is spaced a preset distance from the edge position of the sunken ground layer 3, that is, it is not connected to the edge position. Specifically, the end of the horizontal branch 33 corresponding to the microstrip feeder 12 extends to the edge position.

[0046] Preferably, the vertical branch 32 of the T-shaped slot 31 provided in the sunken ground layer 3 corresponds to the trapezoidal radiation patch 11 in the radiation layer 1 in the hierarchical structure, and the length of the vertical branch 32 is the same as the value of the height of the trapezoidal radiation patch 11. That is, from the front perspective of the hierarchical structure, the trapezoidal radiation patch 11 and the T-shaped slot 31 completely overlap.

[0047] In this embodiment, the layout design of the sunken ground layer can effectively change the magnetic field distribution of the radiation layer and the ground layer, and introduce resonance modes, so as to further increase the bandwidth and optimize the reflection coefficient in the band. At the same time, it can also convert the directional antenna into an omnidirectional antenna; in addition, it also has the advantages of simple structure and few parameters to be optimized.

[0048] Embodiment 2 of the present invention is as follows:

[0049] Please refer to Figures 4 to 14 , this embodiment is further expanded based on Embodiment 1, and specifically optimizes the parameters of the radiation layer and the defect layer of the antenna to obtain the desired antenna performance.

[0050] For the antenna structure described in Embodiment 1, its working center frequency is mainly determined by the parameters of the radiation patch constituting the radiation layer; its radiation performance is mainly determined by the parameters of the T-shaped slot in the defect ground layer.

[0051] In this embodiment, in combination with Figure 2 and Figure 4 it can be known that the overall size of the circuit board formed by laminating the radiation layer 1, the dielectric layer 2 and the defect ground layer 3 is length L G * width W G ; among them, the preferred value range of the length L G is 23 - 27 mm; the width W GThe preferred value range is 22 - 26 mm. In a preferred example, the overall size of the circuit board is length L G * width W G = 25 mm * 24 mm.

[0052] As Figure 4 shown is the front side of the circuit board layout. Combining Figure 2 it can be known that for the trapezoidal radiation patch 11 in the radiation layer 1 thereon, the upper base W RU has a preferred value range of 7.1 - 8.9 mm, the lower base W RD has a preferred value range of 8 - 10 mm, and the height L R has a preferred value range of 7.5 - 8.5 mm. In a preferred example, the size of the trapezoidal radiation patch 11 is upper base W RU = 7.1 mm, lower base W RD = 9.0 mm, and height L R = 8.0 mm. The distance D1 from one end of the upper base of the trapezoidal radiation patch 11 to the corresponding dielectric layer edge (i.e., the circuit board edge) preferably has a value range of 8 - 12 mm; the distance D2 from the lower base of the trapezoidal radiation patch 11 to the corresponding dielectric layer edge (i.e., the circuit board edge) preferably has a value range of 6 - 10 mm. In a preferred example, the distance D1 from one end of the upper base of the trapezoidal radiation patch to the upper edge of the dielectric board is 10.4 mm, and the distance D2 from the lower base to the corresponding dielectric board edge is 8.0 mm.

[0053] For the microstrip feeder 12 in the radiation layer 1, the length L F has a preferred value range of 6 - 10 mm, and the width W F has a preferred value range of 1.5 - 1.6 mm. In a preferred example, the size of the microstrip feeder 12 is L F * W F = 8.0 * 1.53 mm. Preferably, the microstrip feeder 12 is a 50 - ohm feeder.

[0054] As Figure 5 shown is the back side of the circuit board layout. Combining Figure 3 it can be known that for the vertical branch 32 of the T - shaped slot 31 opened in the sunken ground layer 3 thereon, the length L S1 has a preferred value range of 7.5 - 8.5 mm, and the width W S2 has a value range of 12.0 - 14.0 mm; the distance between the vertical branch 32 and one end of the horizontal branch 33 on the same side as the microstrip feeder, that is, the length L F of the microstrip feeder has a value range of 6 - 10 mm, and the distance L S2 between the vertical branch and the other end (i.e., the end far from the microstrip feeder) has a value range of 3.0 - 5.0 mm. The width W of the horizontal branch of the T - shaped slotS1 The preferred value range is 2 - 3 mm. In a preferred example, the size of the T-shaped slot is L S1 = 8 mm, W S2 = 13.0 mm, L F = 8.0 mm, L S2 = 5.0 mm, W S1 = 2.5 mm.

[0055] In a preferred example of this embodiment, the dielectric constant of the dielectric layer is 4.4, the dielectric loss is 0.02, and the thickness is 0.8 mm; the metal layer is copper-plated and the thickness is 0.035 mm.

[0056] Next, experimental data will be used to verify the expected antenna performance that can be achieved by the preferred values of the key parameters in the miniaturized ultra-wideband antenna with notch characteristics provided in this embodiment.

[0057] As Figure 6 shown, it is the variation of the miniaturized planar ultra-wideband antenna provided in this embodiment with the parameter W S1 changing. It can be seen that as the width W S1 of the horizontal branch of the T-shaped slot in the sunken ground increases, the reflection coefficient within the passband of the antenna becomes better and the passband becomes wider. Based on this, in this embodiment, by limiting the width W S1 of the horizontal branch of the T-shaped slot in the sunken ground to a preferred value range of 2 - 3 mm, with an optimal value of 2.5 mm, it will be possible to make the bandwidth of the antenna wider and the impedance matching better within the preferred range, especially when the optimal value is reached, the bandwidth is the widest and the impedance matching is the best.

[0058] As Figure 7 shown, it is the variation of the miniaturized planar ultra-wideband antenna provided in this embodiment with the parameter L S2 changing. It can be seen that as the width W S2 of the vertical branch of the T-shaped slot in the sunken ground increases, the reflection coefficient within the passband of the antenna becomes better in the low-frequency part, first becomes better and then worse in the middle-frequency part, and is good in the high-frequency part. Based on this, in this embodiment, by limiting the width W S2 of the vertical branch of the T-shaped slot in the sunken ground to a preferred value range of 12.0 - 14.0 mm, with an optimal value of 10.5 mm, it will be possible to make the bandwidth of the antenna wider and the impedance matching better within the preferred range, especially when the optimal value is reached, the bandwidth is the widest and the impedance matching is the best.

[0059] As Figure 8 shown, it is the variation of the miniaturized planar ultra-wideband antenna provided in this embodiment with the parameter L S1 changing. It can be seen that as the length L S1As it increases, the low-frequency part of the reflection coefficient within the passband of the antenna improves, the middle-frequency part deteriorates, the high-frequency part improves, and it has the widest bandwidth when L S1 = 8.0 mm. Based on this, in this embodiment, by limiting the length L S1 of the vertical branch of the T-shaped slot to a preferred value range of 7.5 - 8.5 mm, with an optimal value of 8 mm, it will be possible to widen the bandwidth and improve the impedance matching of the antenna within the preferred range. Especially when at the optimal value, the bandwidth is the widest and the impedance matching is the best.

[0060] As Figure 9 shown, it is the variation of the miniaturized planar ultra-wideband antenna provided in this embodiment with the parameter L S2 changing. It can be seen that as the distance L S2 between the end of the vertical branch and the horizontal branch of the T-shaped slot in the sunken ground layer that is far from the microstrip feeder increases, the reflection coefficient of the antenna improves in the low-frequency part, improves in the middle-frequency part, deteriorates in the high-frequency part, and the passband widens. Based on this, in this embodiment, by limiting the distance L S2 between the end of the vertical branch and the horizontal branch of the T-shaped slot that is far from the microstrip feeder to a value range of 3.0 - 5.0 mm, with an optimal value of 5.0 mm, it will be possible to make the antenna have the widest bandwidth and the best impedance matching when at the optimal value.

[0061] As Figure 10 shown, it is the variation of the miniaturized planar ultra-wideband antenna provided in this embodiment with the parameter W RU changing. It can be seen that as the upper base W RU of the trapezoidal radiation patch in the radiation layer increases, the reflection coefficient of the antenna remains unchanged in the low-frequency part, deteriorates first, then improves, then deteriorates again in the middle-frequency part, deteriorates in the high-frequency part, and the bandwidth narrows. Based on this, in this embodiment, by limiting the upper base W RU of the trapezoidal radiation patch to a value range of 7.1 - 8.9 mm, with an optimal value of 7.1 mm, it will be possible to widen the bandwidth and improve the impedance matching of the antenna within the preferred range. Especially when at the optimal value, the bandwidth is the widest and the impedance matching is the best.

[0062] Based on the above analysis, combined with Figure 4 and Figure 5 , the optimized parameter examples of the miniaturized planar ultra-wideband antenna provided in this embodiment are as follows:

[0063] L G = 25.0 mm, W G = 24.0 mm, L S1 = 8 mm, L S2 = 5 mm, W S1 = 2.5 mm, W S2 = 13.0 mm, W RD = 9.0 mm,

[0064] L R = 8.0 mm, D1 = 10.4 mm, D2 = 8.0 mm, L F = 8.0 mm, W F = 1.53 mm.

[0065] As Figure 11 shown, it is the simulation result of the reflection coefficient of the miniaturized planar ultra-wideband antenna corresponding to the above optimization parameter example. It can be seen that the bandwidth range of the reflection coefficient of this antenna less than -10 dB is from 3.04 to 10.78 GHz, the center frequency is 6.91 GHz, the absolute bandwidth is 7.74 GHz, and the relative bandwidth is 112%, showing the characteristics of ultra-wideband.

[0066] As Figures 12 - 14 shown, it is the radiation pattern of the miniaturized planar ultra-wideband antenna corresponding to the above optimization parameter example. It can be seen that this miniaturized planar ultra-wideband antenna is an omnidirectional antenna and has high gain.

[0067] Embodiment III

[0068] This embodiment is further expanded based on Embodiment I or Embodiment II, and provides a mobile terminal including the above miniaturized planar ultra-wideband antenna.

[0069] In some specific embodiments, the mobile terminal may be a mobile phone, a walkie-talkie, a tablet computer or other mobile terminals with the need to utilize an antenna to achieve wireless communication requirements.

[0070] The mobile terminal provided in this embodiment, by equipping the miniaturized planar ultra-wideband antenna provided in Embodiment I or Embodiment II, and utilizing its ultra-wideband, omnidirectional and high-gain antenna performance and miniaturized characteristics, will be able to significantly improve the wireless communication performance and positioning performance of the mobile terminal.

[0071] The above are only the embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. All equivalent transformations made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in related technical fields, are equally included in the patent protection scope of the present invention.

Claims

1. A miniaturized planar ultra-wideband antenna, characterized in that: It comprises a radiation layer, a dielectric layer and a recessed stratum which are stacked in sequence; the radiation layer comprises a trapezoidal radiation patch and a microstrip feeder; one end of the microstrip feeder is connected to the upper bottom of the trapezoidal radiation patch; a T-shaped gap is provided on the recessed stratum; the vertical branch of the T-shaped gap corresponds to the trapezoidal radiation patch, and the horizontal branch of the T-shaped gap is parallel to the microstrip feeder.

2. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The transverse branch of the T-shaped gap is arranged at the edge of the depressed stratum.

3. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The other end of the microstrip feed line is connected to the edge of the radiation layer; One end of the transverse branch corresponding to the other end of the microstrip feeder extends to the edge of the depressed formation, and the other end is spaced a preset distance from the edge of the depressed formation.

4. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The width of the horizontal branch of the T-shaped gap ranges from 2 to 3 mm; the width of the vertical branch of the T-shaped gap ranges from 12.0 to 14.0 mm, and the length ranges from 7.5 to 8.5 mm.

5. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The distance between the horizontal branch and one end of the vertical branch of the T-shaped gap ranges from 6 to 10 mm, and the distance between the horizontal branch and the other end of the vertical branch ranges from 3 to 5 mm.

6. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The upper base of the trapezoidal radiation patch has a value range of 7.1-8.9 mm, the lower base has a value range of 8-10 mm, and the height has a value range of 7.5-8.5 mm.

7. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The length of the microstrip feed line ranges from 6 to 10 mm, and the width ranges from 1.5 to 1.6 mm.

8. The miniaturized planar ultra-wideband antenna according to claim 1, characterized in that: The distance between the lower base of the trapezoidal radiation patch and the edge of the corresponding radiation layer ranges from 6 to 10 mm; the distance between the end of the upper base of the trapezoidal radiation patch corresponding to the horizontal branch and the edge of the corresponding radiation layer ranges from 8 to 12 mm.

9. A mobile terminal, characterized in that: The miniaturized planar ultra-wideband antenna comprises any one of claims 1 to 8.

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