A small dual-frequency dual-polarized antenna

Abstract

The application relates to a small-sized dual-frequency dual-polarized antenna which comprises a dielectric plate and a radiation unit arranged on the dielectric plate, the radiation unit comprises two pairs of arm groups arranged orthogonally, each pair of the arm groups comprises two dual-frequency oscillator arms arranged at intervals and diagonally, two adjacent dual-frequency oscillator arms are arranged at intervals in a clockwise direction and are formed with a coupling gap, and a frequency-reducing gap for reducing a resonant frequency is arranged on the dual-frequency oscillator arm. The coupling gap improves impedance matching of a low-frequency band and a high-frequency band, reduces cross-polarization radiation, improves antenna isolation, increases a current path through the frequency-reducing gap, reduces the resonant frequency, reduces the size of the antenna, improves radiation efficiency, and improves horizontal plane coverage.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and in particular to a small dual-frequency dual-polarized antenna. Background Technology

[0002] With the development of Wi-Fi technology, the requirements for antennas are becoming increasingly stringent, and miniaturization is a common trend. Miniaturization of Wi-Fi antennas for terminals allows for smaller product sizes. One dual-band dual-polarization antenna can replace four single-band single-polarization antennas, which is of great value in the current scenario where Wi-Fi 7 products typically use 4 to 8 antennas. Antennas that simultaneously meet the requirements of miniaturization and high isolation are irreplaceable in product miniaturization design.

[0003] A conventional dual-band antenna has only one polarization, making it difficult to simultaneously meet the requirements of multi-antenna layout and isolation in MIMO applications, thus limiting the structural layout. New miniaturized terminal products require miniaturized dual-band dual-polarization antenna designs, but conventional dual-band antennas are too large and cannot meet the required isolation. Summary of the Invention

[0004] This application provides a small dual-band dual-polarization antenna. By using coupling slots, it improves impedance matching between low-frequency and high-frequency bands, reduces cross-polarization radiation, and increases antenna isolation. By using frequency reduction slots, it increases the current path, lowers the resonant frequency, reduces antenna size, improves radiation efficiency, and increases horizontal coverage.

[0005] This application provides a miniature dual-band dual-polarization antenna, which includes: Medium plate; A radiation unit is disposed on the dielectric substrate. The radiation unit includes two pairs of arm groups arranged orthogonally. Each pair of arm groups includes two dual-frequency oscillator arms that are spaced apart and arranged diagonally. Along the clockwise direction, two adjacent dual-frequency oscillator arms are spaced apart and have coupling gaps. The dual-frequency oscillator arm is provided with a frequency reduction gap for lowering the resonant frequency.

[0006] In some embodiments, the frequency reduction gap is parallel to the side of the dielectric plate, and the frequency reduction gap is a single-opening gap that starts from one side of the dual-frequency vibrator arm and extends into the interior of the dual-frequency vibrator arm.

[0007] In some embodiments, the frequency reduction gap includes a straight gap and / or an L-shaped gap.

[0008] In some embodiments, the frequency reduction gap includes multiple L-shaped gaps, and the initial openings of at least two of the L-shaped gaps are located on two different sides of the dual-frequency oscillator arm.

[0009] In some embodiments, the frequency reduction gap includes at least one straight gap and at least one L-shaped gap, and the starting openings of one straight gap and one L-shaped gap are located on the same side of the dual-frequency oscillator arm, or on two different sides of the dual-frequency oscillator arm.

[0010] In some embodiments, in one pair of arm assemblies, one of the two dual-frequency vibrating arms is provided with a first hollow area, and the other dual-frequency vibrating arm is provided with a power supply branch that extends into the first hollow area.

[0011] In some embodiments, a second hollow area is formed between two adjacent dual-frequency oscillator arms in a clockwise direction. One end of the second hollow area is connected to the coupling gap, and the other end extends to the side of the dielectric plate.

[0012] In some embodiments, the second hollow area is triangular, and one vertex of the triangle is connected to the coupling gap, so that the dual-frequency oscillator arm is hexagonal.

[0013] In some embodiments, the second cutout area includes triangular cutout sub-areas connected to rectangular cutout sub-areas, the triangular cutout sub-areas being located between the rectangular cutout sub-areas and the coupling gap, and one of its vertices being connected to the coupling gap.

[0014] In some embodiments, the radiating units are provided on both opposite walls of the dielectric plate, and the dual-frequency oscillator arms of the radiating units are connected to the balun support.

[0015] The beneficial effects of the technical solution provided in this application include: This application provides a small dual-band dual-polarization antenna. Along a clockwise direction, adjacent dual-band dipole arms are spaced apart and have coupling slots, resulting in four cross-shaped coupling slots in the middle region of the radiating element on the dielectric substrate. On one hand, by adjusting the length and width of the coupling slots, impedance matching between the low-frequency and high-frequency bands can be significantly improved, increasing antenna isolation and reducing cross-polarization radiation, thereby enhancing antenna performance. On the other hand, due to the coupling effect of the coupling slots, the cross-polarization currents of the two dual-band dipole arms forming the arm group cancel each other out through the coupling slots, reducing cross-polarization radiation and further improving antenna isolation, thus enhancing antenna performance.

[0016] The dual-frequency vibrator arm is provided with a frequency reduction gap, which can increase the current path, reduce the resonant frequency, reduce the antenna size, improve the radiation efficiency of the small dual-frequency dual-polarized antenna, and increase the horizontal coverage range. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a small dual-frequency dual-polarized antenna provided in Embodiment 1 of this application; Figure 2 This is a schematic diagram of a small dual-frequency dual-polarized antenna provided in Embodiment 2 of this application; Figure 3 This is a schematic diagram of a small dual-frequency dual-polarization antenna provided in Embodiment 3 of this application; Figure 4 This is a schematic diagram of a small dual-frequency dual-polarization antenna provided in Embodiment 4 of this application; Figure 5 This is the antenna echo S11 diagram of Embodiment 1 of this application; Figure 6 This is an antenna gain diagram of Embodiment 1 of this application; Figure 7 This is the antenna echo S11 diagram of Embodiment 2 of this application; Figure 8 This is an antenna gain diagram of Embodiment 2 of this application; Figure 9 This is a radiation efficiency diagram of Embodiment 2 of this application; Figure 10 This is the antenna echo S11 diagram of Embodiment 3 of this application; Figure 11 This is the antenna gain diagram for Embodiment 3 of this application; Figure 12 This is a radiation efficiency diagram of Embodiment 3 of this application; Figure 13 This is the antenna echo S11 diagram of Embodiment 4 of this application; Figure 14 This is the antenna gain diagram for Embodiment 4 of this application; Figure 15 This is an isolation diagram of Embodiment 4 of this application.

[0019] In the diagram: 1. Medium plate; 10. Second cutout area; 100. Rectangular cutout sub-area; 101. Triangular cutout sub-area; 2. Dual-frequency vibrator arm; 20. First cutout area; 21. Feeding branch; 3. Coupling gap; 4. Frequency reduction gap; 40. Initial opening; 41. I-shaped gap; 42. L-shaped gap; 5. Balun support. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] See Figure 1 As shown in the figure, this application provides a small dual-band dual-polarized antenna, which can be applied to the field of built-in antennas in wireless terminal products. The product form can include home gateways, wireless APs, CPEs, FTTRs, set-top boxes, IoT terminals, mobile phones and other products.

[0022] The antenna includes a dielectric substrate 1 and a radiating element. The radiating element is disposed on the dielectric substrate 1. Specifically, the dielectric substrate 1 can be a common PCB board. The dielectric substrate 1 can be square, such as a square or a rectangle. If necessary, other shapes can also be used. The radiating element is a metal layer (such as a copper layer) electroplated on the dielectric substrate 1. The radiating element includes two pairs of arms arranged orthogonally. Each pair of arms includes two dual-frequency dipole arms 2 that are spaced apart and arranged diagonally. Along the clockwise direction, two adjacent dual-frequency dipole arms 2 are spaced apart and form a coupling gap 3. The dual-frequency dipole arms 2 are provided with a frequency reduction gap 4 for reducing the resonant frequency.

[0023] The radiation unit of the above embodiment includes four dual-frequency vibrating arms 2 of the same shape and size, which are rotationally symmetrical. Two relatively spaced and diagonally arranged dual-frequency vibrating arms 2 cooperate to form a first pair of arms, which is equivalent to a dual-frequency +45° polarized half-wave array. The other two relatively spaced and diagonally arranged dual-frequency vibrating arms 2 cooperate to form a second pair of arms, which is equivalent to a dual-frequency -45° polarized half-wave array. The two pairs of arms are orthogonal to each other to form dual-frequency dual-polarization radiation.

[0024] In this application, adjacent dual-frequency dipole arms 2 are spaced apart along a clockwise direction, forming coupling gaps 3, resulting in four cross-shaped coupling gaps 3 forming the radiating element in the middle region of the dielectric substrate 1. On one hand, by adjusting the length and width of the coupling gaps, impedance matching between low and high frequency bands can be significantly improved, antenna isolation increased, and cross-polarization radiation reduced, thereby enhancing antenna performance. On the other hand, the width of the coupling gaps can be reduced to less than 0.01 times the wavelength, making them tightly coupled gaps. Due to the coupling effect of the coupling gaps, the cross-polarization currents of the two dual-frequency dipole arms forming the arm group cancel each other out through the coupling gaps, reducing cross-polarization radiation and further improving antenna isolation (reaching over 25 dB), thereby enhancing antenna performance.

[0025] In this application, the dual-frequency vibrating arm 2 is provided with a frequency reduction gap 4. The frequency reduction gap 4 can increase the current path, reduce the resonant frequency, reduce the antenna size, improve the radiation efficiency of the small dual-frequency dual-polarized antenna, increase the horizontal coverage range, and simulate the radiation efficiency of the WiFi dual-frequency antenna to be greater than 90%.

[0026] See Figure 1 As shown, the frequency reduction gap 4 is parallel to the side of the dielectric substrate 1. The dielectric substrate 1 is typically square, such as a rectangular prism. Therefore, the length extension direction of the frequency reduction gap 4 is parallel to the side of the dielectric substrate 1. The frequency reduction gap 4 is a single-opening gap formed by starting with an opening 40 on one side of the dual-frequency vibrator arm 2 and extending into the interior of the dual-frequency vibrator arm 2. The advantage of designing the frequency reduction gap 4 parallel to the side of the dielectric substrate is that it avoids the end stub current formed by the frequency reduction gap at the end of the dual-frequency vibrator arm 2 away from the four coupling gaps 3 in a cross-shaped structure from being opposite in direction to the beginning current of the dual-frequency vibrator arm 2 near the four coupling gaps 3 in a cross-shaped structure. This maximizes the strength of the far-field superposition signal. If it were parallel to the diagonal, the end stub current would be opposite to the beginning current, which would weaken the far-field superposition effect.

[0027] See Figure 1 As shown, the frequency reduction gap 4 includes a straight gap 41 and / or an L-shaped gap 42. The straight gap 41 is parallel to one of the two adjacent sides of the dielectric substrate 1, and the L-shaped gap 42 is parallel to the two adjacent sides of the dielectric substrate 1.

[0028] Understandably, a single straight gap 41 can be set on the dual-frequency oscillator arm 2, or... Figure 2 and Figure 3 Similarly, while only an L-shaped gap 42 is set on the dual-frequency vibrator arm 2, a straight gap 41 and an L-shaped gap 42 can also be set on the dual-frequency vibrator arm 2 at the same time.

[0029] It is understandable that the number of the aforementioned straight-line slots 41 and L-shaped slots 42 can be adjusted according to the actual antenna performance requirements.

[0030] It is understandable that the length and width of the aforementioned straight slit 41 and L-shaped slit 42 can be adjusted according to the actual antenna performance requirements.

[0031] In one example, see Figure 1 As shown, the frequency reduction gap 4 includes multiple L-shaped gaps 42, and the starting openings 40 of at least two of the L-shaped gaps 42 are located on two different sides of the dual-frequency oscillator arm 2. The advantage of this design is that it can increase the current path.

[0032] See another example. Figure 1 As shown, the frequency reduction gap 4 includes at least one straight gap 41 and at least one L-shaped gap 42, and the starting opening 40 of one straight gap 41 and one L-shaped gap 42 is located on the same side of the dual-frequency vibrator arm 2, or on two different sides of the dual-frequency vibrator arm 2.

[0033] For the radiating elements on dielectric substrate 1, in order to enable power feeding, see [reference needed]. Figure 1 As shown, in one pair of arm groups comprising two dual-frequency vibrating arms 2, one dual-frequency vibrating arm 2 is provided with a first hollow area 20, and the other dual-frequency vibrating arm 2 is provided with a feed branch 21 extending into the first hollow area 20. Feeding can be achieved using one coaxial line on this pair of arm groups, and another coaxial line can be used on the other pair of arm groups, achieving cross-feeding with an isolation of 25dB or more.

[0034] See Figure 1 As shown, a second hollow area 10 is formed between two adjacent dual-frequency vibrating arms 2 in a clockwise direction. One end of the second hollow area 10 is connected to the coupling gap 3, and the other end extends to the side of the dielectric plate 1. Through the separation of the coupling gap 3 and the second hollow area 10, each dual-frequency vibrating arm 2 is an independent structure.

[0035] See Figure 1 As shown, the second hollow area 10 is triangular, and one vertex of the triangle is connected to the coupling gap 3, so that the dual-frequency oscillator arm 2 is hexagonal. The advantage of making the dual-frequency oscillator arm 2 hexagonal is that it allows for a larger radiation arm area while ensuring a +45° polarization isolation.

[0036] See Figure 3 As shown, the second hollow area 10 includes a triangular hollow sub-area 101 connected to a rectangular hollow sub-area 100. The triangular hollow sub-area 101 is located between the rectangular hollow sub-area 100 and the coupling gap 3, and one of its vertices is connected to the coupling gap 3.

[0037] See Figure 4 As shown, the radiation units are provided on two opposite walls of the dielectric plate 1, and the dual-frequency oscillator arm 2 of the radiation unit is connected to the balun bracket 5.

[0038] With radiating units set on both sides, a coaxial vertical feeding structure can be designed using a balun bracket 5, with an isolation of over 30dB.

[0039] Example 1 like Figure 1As shown, the antenna supports dimensions of 25mm × 25mm × 1mm, including a straight slot and two L-shaped slots. The antenna size is less than 1 / 4 wavelength at low frequencies, and the dual-polarization isolation is above 25dB. The dual-frequency dipole arms of the antenna are hexagonal, and each dual-frequency dipole arm includes one straight slot and two L-shaped slots on the side near the dielectric substrate, which can reduce the resonant frequency and reduce the antenna size; the dual-frequency dipole arms are coaxially fed. Figure 5 The S11 curve for this antenna shows that S11 < -10dB in the 2400MHz–2500MHz and 5000MHz–6000MHz frequency bands, indicating good echo performance in these bands. Figure 6 The antenna gain curve shows that it is greater than 1.4 dBi in the 2400MHz~2500MHz band and 3 dBi in the 5000MHz~6000MHz band, indicating good gain performance. Therefore, the antenna supports the 2400MHz~2500MHz and 5000MHz~6000MHz frequency bands.

[0040] Example 2 like Figure 2 As shown, the antenna measures 30mm × 30mm × 1mm, including an L-shaped slot. The antenna size is close to one-quarter of the low-frequency wavelength. Figure 7 The S11 curve for this antenna shows that S11 < -10dB in the 2400MHz–2500MHz and 5000MHz–6000MHz frequency bands, indicating good echo performance in these bands. Figure 8 The antenna gain curve shows gains greater than 1.79 dBi in the 2400MHz–2500MHz and 2.48 dBi in the 5000MHz–6000MHz range, indicating good gain performance. Figure 9 The antenna has a wider standing wave bandwidth and higher radiation efficiency than Example 1. The simulated WiFi dual-band antenna has a radiation efficiency of more than 90%. It can be seen that the antenna supports the 2400MHz~2500MHz and 5000MHz~6000MHz frequency bands.

[0041] Example 3 like Figure 3 As shown, Example 3 is a variation of Example 2, in which the end of the dual-frequency oscillator arm is extended into a rectangle so that the distance between the end of the L-shaped gap away from the initial opening and the side of the dual-frequency oscillator arm is wider, thus avoiding the L-shaped gap from cutting off the dual-frequency oscillator arm. The performance indicators are similar to those of Example 2. Figure 10 The S11 curve for this antenna shows that S11 < -10dB in the 2400MHz–2500MHz and 5000MHz–6000MHz frequency bands, indicating good echo performance in these bands. Figure 11The antenna gain curve shows gains greater than 1.4 dBi in the 2400MHz–2500MHz and 2.39 dBi in the 5000MHz–6000MHz range, indicating good gain performance. Figure 12 As can be seen from the antenna's radiation efficiency, the antenna supports the 2400MHz~2500MHz and 5000MHz~6000MHz frequency bands.

[0042] Example 4 like Figure 4 As shown, the antenna measures 25mm × 25mm × 11mm. In Example 1, the single-sided radiating element on the dielectric substrate is replaced with a double-sided radiating element. The antenna is fed perpendicularly to the dielectric substrate via a coaxial cable, and a balun bracket is added. This eliminates the influence of the coaxial cable trace, resulting in a better radiation pattern. Figure 13 The S11 curve for this antenna shows that S11 < -10dB in the 2400MHz–2500MHz and 5000MHz–6000MHz frequency bands, indicating good echo performance in these bands. Figure 14 The antenna gain curve shows gains greater than 1.8 dBi in the 2400 MHz–2500 MHz range and 2.343 dBi in the 5000 MHz–6000 MHz range, indicating good gain performance. Figure 15 The isolation of this antenna is above 30dB for dual polarization. Therefore, this antenna supports the 2400MHz–2500MHz and 5000MHz–6000MHz frequency bands.

[0043] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0044] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A compact dual-band dual-polarized antenna, characterized in that, It includes: Medium plate (1); A radiation unit is disposed on the dielectric plate (1). The radiation unit includes two pairs of arms arranged orthogonally, and each pair of arms includes two dual-frequency oscillator arms (2) that are spaced apart and arranged diagonally. Along the clockwise direction, two adjacent dual-frequency oscillator arms (2) are spaced apart and have a coupling gap (3). The dual-frequency oscillator arm (2) is provided with a frequency reduction gap (4) for reducing the resonant frequency.

2. The miniature dual-frequency dual-polarization antenna as described in claim 1, characterized in that: The frequency reduction gap (4) is parallel to the side of the dielectric plate (1). The frequency reduction gap (4) is a single-opening gap formed by starting with one side of the dual-frequency vibrator arm (2) as the opening (40) and extending into the interior of the dual-frequency vibrator arm (2).

3. The miniature dual-frequency dual-polarization antenna as described in claim 1 or 2, characterized in that: The frequency reduction gap (4) includes a straight gap (41) and / or an L-shaped gap (42).

4. The miniature dual-frequency dual-polarization antenna as described in claim 3, characterized in that: The frequency reduction gap (4) includes multiple L-shaped gaps (42), and the starting openings (40) of at least two of the L-shaped gaps (42) are located on two different sides of the dual-frequency oscillator arm (2).

5. The miniature dual-frequency dual-polarization antenna as described in claim 3, characterized in that: The frequency reduction gap (4) includes at least one of the straight gaps (41) and at least one of the L-shaped gaps (42), and the starting openings (40) of one of the straight gaps (41) and one of the L-shaped gaps (42) are located on the same side of the dual-frequency vibrator arm (2), or on two different sides of the dual-frequency vibrator arm (2).

6. The miniature dual-frequency dual-polarization antenna as described in claim 1, characterized in that: In one of the pairs of arm groups, one of the dual-frequency vibrating arms (2) is provided with a first hollow area (20), and the other dual-frequency vibrating arm (2) is provided with a power supply branch (21) that extends into the first hollow area (20).

7. The miniature dual-frequency dual-polarization antenna as described in claim 1, characterized in that: Along the clockwise direction, a second hollow area (10) is also formed between two adjacent dual-frequency oscillator arms (2). One end of the second hollow area (10) is connected to the coupling gap (3), and the other end extends to the side of the dielectric plate (1).

8. The miniature dual-frequency dual-polarization antenna as described in claim 7, characterized in that: The second hollow area (10) is triangular, and one vertex of the triangle is connected to the coupling gap (3) so that the dual-frequency oscillator arm (2) is hexagonal.

9. The miniature dual-frequency dual-polarization antenna as described in claim 7, characterized in that: The second hollow area (10) includes a triangular hollow sub-area (101) connected to a rectangular hollow sub-area (100). The triangular hollow sub-area (101) is located between the rectangular hollow sub-area (100) and the coupling gap (3), and one of its vertices is connected to the coupling gap (3).

10. The miniature dual-frequency dual-polarization antenna as described in claim 1, characterized in that: The radiation unit is provided on both opposite walls of the dielectric plate (1), and the dual-frequency oscillator arm (2) of the radiation unit is connected to the balun bracket (5).

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