Antenna array and double-feed circularly polarized broadband antenna

Abstract

According to the main technology, a substrate module comprises a parasitic element and a radiator, the central point of the parasitic element and the central point of the radiator are projected at the same point in the first direction, a third substrate unit is stacked below the substrate module and provided with a first slot and a second slot, and the third substrate unit is provided with a second slot. The fourth substrate unit is stacked under the third substrate unit and has a first feed-in line and a second feed-in line, and when the fourth substrate unit is operated in an emission mode, a signal is electromagnetically induced from the first feed-in line and the second feed-in line to the first slotted hole and the second slotted hole, then electromagnetically induced to the radiator, and then electromagnetically induced to the parasitic element to send an output electromagnetic wave. The coupling effect of the parasitic element and the radiator expands the bandwidth, and the purpose of integrating a transmitting frequency band and a receiving frequency band on the same antenna is achieved.

Description

Technical Field

[0001] The invention relates to an antenna technology, in particular to an antenna array and a dual-feed circularly polarized broadband antenna. Background Art

[0002] In the existing antenna design of the KU band low-orbit satellite system, the frequency band for reception is 10.7 GHz to 12.7 GHz, and the frequency band for transmission is 14.0 GHz to 14.5 GHz. The existing antenna design separates the receiving antenna from the transmitting antenna, which will result in two antenna devices of different sizes. If the RF power is directly fed to the radiator through the via, this design method cannot achieve the broadband effect, and the two antenna devices increase the mold opening cost. Therefore, how to integrate it into an antenna with a frequency band that can cover the transmission band and the reception band is the current research direction. Summary of the invention

[0003] An object of the present invention is to provide an antenna array and a dual-feed circularly polarized broadband antenna that expands bandwidth and integrates a transmit frequency band and a receive frequency band into the same antenna.

[0004] Therefore, the antenna array includes a first antenna unit, a second antenna unit, a third antenna unit, and a fourth antenna unit.

[0005] The second antenna unit is rotated 90 degrees counterclockwise compared to the first antenna unit and is disposed in an X-axis direction together with the first antenna unit.

[0006] The third antenna unit is rotated 90 degrees counterclockwise compared to the second antenna unit and is disposed in a Y-axis direction together with the second antenna unit.

[0007] The fourth antenna unit is rotated 90 degrees counterclockwise compared to the third antenna unit and is disposed in the X-axis direction together with the third antenna unit.

[0008] The first antenna unit to the fourth antenna unit include a dual-feed circularly polarized broadband antenna.

[0009] Therefore, the dual-feed circularly polarized broadband antenna includes a substrate module, a third substrate unit and a fourth substrate unit.

[0010] The substrate module includes a parasitic element and a radiator disposed under the parasitic element and with a first thickness from the parasitic element, and the center point of the parasitic element and the center point of the radiator are projected onto the same point along a first direction.

[0011] The third substrate unit is stacked under the substrate module and has a first slot and a second slot which are a second thickness away from the radiator.

[0012] The fourth substrate unit is stacked under the third substrate unit and has a first feeding line and a second feeding line. The first feeding line is a third thickness away from the first slot, and the second feeding line is a third thickness away from the second slot.

[0013] When operating in a transmitting mode, a signal is electromagnetically induced by the first feeding line and the second feeding line to the first slot and the second slot respectively, and then electromagnetically induced by the first slot and the second slot to the radiator, and then electromagnetically induced by the radiator to the parasitic element, and an output electromagnetic wave is sent by the parasitic element. When operating in a receiving mode, an input electromagnetic wave from the external environment is received by the parasitic element and electromagnetically induced to the radiator, and then electromagnetically induced by the radiator to the first slot and the second slot, and then electromagnetically induced to the first feeding line and the second feeding line respectively.

[0014] The dual-feed circularly polarized broadband antenna of the present invention comprises a substrate module further comprising a first substrate and a second substrate. The first substrate comprises a first surface on which the parasitic element is arranged and a second surface. The second substrate comprises a first surface connected to the second surface of the first substrate and a second surface on which the radiator is arranged.

[0015] The dual-feed circularly polarized broadband antenna of the present invention, the substrate module also includes a first adhesive layer, the first adhesive layer is used to adhere the first substrate and the second substrate, the distance between the first surface of the first substrate and the second surface of the second substrate is close to the first thickness.

[0016] The dual-feed circularly polarized broadband antenna of the present invention comprises a third substrate unit having a third substrate having a first surface and a second surface where the first slot and the second slot are arranged, and the distance between the first surface and the second surface of the third substrate is close to the second thickness.

[0017] The dual-feed circularly polarized broadband antenna of the present invention has a fourth substrate unit having a first surface and a second surface on which the first feed line and the second feed line are arranged. The distance between the first surface and the second surface of the fourth substrate is close to the third thickness.

[0018] The dual-feed circularly polarized broadband antenna of the present invention further comprises a second adhesive layer, and the second adhesive layer is used for bonding the third substrate unit and the substrate module.

[0019] The dual-feed circularly polarized broadband antenna of the present invention further comprises a third adhesive layer, and the third adhesive layer is used for bonding the third substrate unit and the fourth substrate unit.

[0020] The dual-feed circularly polarized broadband antenna of the present invention has a circular shape for the parasitic element and the radiator.

[0021] The dual-feed circularly polarized broadband antenna of the present invention comprises: a first slot hole being a horizontal dumbbell-shaped slot hole with two ends extending along a second direction; a second slot hole being a vertical dumbbell-shaped slot hole with two ends extending along a third direction; a first feed line being a vertical microstrip line extending along the second direction; and a second feed line being a horizontal microstrip line extending along the third direction.

[0022] The effect of the present invention is to expand the bandwidth by utilizing the coupling effect between the parasitic element and the radiator, so as to achieve the purpose of integrating the transmitting frequency band and the receiving frequency band into the same antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the accompanying drawings, in which:

[0024] Figure 1 It is a structural side view of an embodiment of a dual-feed circularly polarized broadband antenna of the present invention;

[0025] Figure 2 It is a stacked diagram of the dual-feed circularly polarized broadband antenna of the present invention;

[0026] Figure 3 This is a top view of the structure of a dual-feed circularly polarized broadband antenna;

[0027] Figure 4 is a top view of the structure of the first slot and the second slot;

[0028] Figure 5 It is the S parameter diagram of dual-feed circularly polarized broadband antenna;

[0029] Figure 6 is the antenna gain diagram of a dual-feed circularly polarized broadband antenna;

[0030] Figure 7 is the axial ratio diagram of the dual-feed circularly polarized broadband antenna;

[0031] Figure 8 is the radiation pattern of the dual-feed circularly polarized broadband antenna;

[0032] Fig. 9 is a top view of the structure of an embodiment of an antenna array of the present invention;

[0033] Fig.10 is the S-parameter diagram of an antenna array with 2×2 antenna elements;

[0034] Fig.11 is the antenna gain pattern of the antenna array;

[0035] Fig.12 is the axial ratio diagram of the antenna array;

[0036] Fig.13 is the radiation pattern of the antenna array. DETAILED DESCRIPTION

[0037] Before the present invention is described in detail, it should be noted that similar elements are denoted by the same reference numerals in the following description.

[0038] See also Figure 1 The structural side view of Figure 2 The stacked structure diagram is an embodiment of the dual-feed circularly polarized broadband antenna of the present invention, which includes a substrate module 1, a second adhesive layer 22, a third substrate unit 3, a third adhesive layer 33, and a fourth substrate unit 4.

[0039] The substrate module 1 includes a first substrate 10, a first adhesive layer 12, a second substrate 20, a parasitic element 11, and a radiator 21 disposed under the parasitic element 11 and at a first thickness from the parasitic element 11, and the parasitic element 11 and the radiator 21 are circular, and the center point of the parasitic element 11 and the center point of the radiator 21 are projected to the same point O along a first direction (Z axis), see Figure 3 : is a top view of the structure of a dual-feed circularly polarized broadband antenna, wherein the diameter of the radiator 21 is designed to be λ / 2, and the parameter λ is the inverse of the dielectric center frequency of the first substrate 10. In this embodiment, the radius of the parasitic element 11 is designed to be 2.2 mm, and the radius of the radiator 21 is designed to be 2.8 mm. The first substrate 10 has a first surface 101 on which the parasitic element 11 is disposed and a second surface 102. The thickness of the first substrate 10 is 1.2 mm, and the dielectric constant ε=3.55. The second substrate 20 has a first surface 201 connected to the second surface 102 of the first substrate 10 and a second surface 202 on which the radiator 21 is disposed. The thickness of the second substrate 20 is 1.2 mm, and the dielectric constant ε=3.55. The first adhesive layer 12 is used to bond the second surface 102 of the first substrate 10 and the first surface 201 of the second substrate 20. The thickness of the first adhesive layer 12 is 0.05 mm, and the dielectric constant ε is 3.5. The distance between the first surface 101 of the first substrate 10 and the second surface 202 of the second substrate 20 in the first state of this embodiment (=2.45 mm) is close to the first thickness (=2.4 mm), but is not limited to this. The second state of this embodiment can also directly use a substrate with a thickness of 2.4 mm to replace the first substrate 10 and the second substrate 20 to bond the two substrates.

[0040] The third substrate unit 3 is stacked under the substrate module 1 and has a third substrate 30, a first slot 31 and a second slot 32 at a second thickness from the radiator 21. The third substrate 30 has a first surface 301 and a second surface 302 where the first slot 31 and the second slot 32 are arranged. The thickness of the third substrate 30 is 1 mm, and the dielectric constant ε=3. Since the radiator 21 is very thin, the second adhesive layer 22 is used to bond the third substrate unit 3 to the second substrate 20 and the radiator 21 of the substrate module 1. The thickness of the second adhesive layer 22 is 0.05 mm, and the dielectric constant ε=3.5. The distance (1 mm) between the first surface 301 and the second surface 302 of the third substrate 30 is close to the second thickness (1.05 mm). The first slot 31 is a horizontal dumbbell-shaped slot with two ends extending along a second direction (X axis) and made of a metal layer. The second slot 32 is a vertical dumbbell-shaped slot with two ends extending along a third direction (Y axis) and made of a metal layer. Figure 4 It is a top view of the structure of the first slot hole 31 and the second slot hole 32 , illustrating the parameter design of the first slot hole 31 and the second slot hole 32 .

[0041] The fourth substrate unit 4 is stacked under the third substrate unit 3 and has a fourth substrate 40, a first feed line 41 and a second feed line 42. The first feed line 41 is a third thickness away from the first slot 31, and the second feed line 42 is a third thickness away from the second slot 32. The fourth substrate 40 has a first surface 401 and a second surface 402 on which the first feed line 41 and the second feed line 42 are disposed. The third adhesive layer 33 is used to bond the third substrate unit 3 and the fourth substrate unit 4. The thickness of the third adhesive layer 33 is 0.05 mm, and the dielectric constant ε=3.5. The thickness of the fourth substrate 40 is 0.15 mm, and the dielectric constant ε=3. The distance between the first surface 401 and the second surface 402 of the fourth substrate 40 (=0.15 mm) is close to the third thickness (=0.2 mm). The first feed line 41 is a vertical microstrip line extending along the second direction (X axis), and the second feed line 42 is a horizontal microstrip line extending along the third direction (Y axis). The length of the first feed line 41 and the width of the second feed line 42 are 4 mm and 0.35 mm respectively.

[0042] When operating in a transmission mode, the signal is electromagnetically induced by the first feeding line 41 and the second feeding line 42 to the first slot 31 and the second slot 32 respectively, and then electromagnetically induced by the first slot 31 and the second slot 32 to the radiator 21, and then electromagnetically induced by the radiator 21 to the parasitic element 11, and the parasitic element 11 sends an output electromagnetic wave.

[0043] When operating in a receiving mode, an input electromagnetic wave from the external environment is received by the parasitic element 11 and electromagnetically induced to the radiator 21, and then electromagnetically induced to the first slot 31 and the second slot 32 by the radiator 21, and then electromagnetically induced to the first feeding line 41 and the second feeding line 42 respectively.

[0044] See also Figure 5 It is an S parameter diagram, which illustrates S11 (input reflection coefficient of the vertical feeding point) corresponding to the first feeding line 41, S22 (output reflection coefficient of the horizontal feeding point) corresponding to the second feeding line 42, and S12 (defining the isolation between the two points S11 and S22. The isolation characteristic measurement purpose is used to determine the mutual influence between antennas when transmitting and receiving signals. The industry isolation standard is usually about -20 to -30 dB). The X-axis indicates two frequency bands TX (14 to 14.5 GHz) and RX (10.7 to 12.7 GHz), and the unit of the Y-axis is dB. Figure 6 It is an antenna gain diagram, which is used to illustrate the gain of two frequency bands TX (14~14.5GHz) and RX (10.7~12.7GHz). Figure 7 It is an axial ratio diagram, where the vertical feed phase is set to 90 degrees and the horizontal feed phase is set to 0 degrees. The axial ratio is defined as the ratio of the major axis to the minor axis of the ellipse. When the axial ratio of the elliptical polarization is infinite, it is linear polarization, and when the axial ratio is 1, it is circular polarization. When two orthogonal vectors in space have the same amplitude and a phase difference of 90 degrees, the polarization state at this time is circular polarization. Figure 8 It is the radiation pattern of the antenna, which is also called the antenna pattern or far-field pattern. It is a graph that describes the dependence between the intensity and direction (angle) of the radio waves emitted by an antenna or other signal source, and is used to illustrate the situations where the frequencies are 10.75 GHz, 11.75 GHz, 12.75 GHz, 14 GHz, and 14.5 GHz.

[0045] See also Fig. 9, is an embodiment of the antenna array of the present invention, comprising M×N antenna units, M≥1, N≥1, and taking 2×2 antenna units as an example, namely a first antenna unit T1, a second antenna unit T2, a third antenna unit T3, and a fourth antenna unit T4, the first antenna unit T1 to the fourth antenna unit T4 are all dual-feed circularly polarized broadband antennas, the second antenna unit T2 is rotated 90 degrees counterclockwise compared to the first antenna unit T1 and is arranged in an X-axis direction with the first antenna unit T1, and the third antenna unit T3 is arranged in an X-axis direction with the first antenna unit T1. The antenna unit T3 is rotated 90 degrees counterclockwise compared to the second antenna unit T2 (that is, the third antenna unit T3 is rotated 180 degrees sequentially with the Z axis as the center compared to the first antenna unit T1) and is both arranged in a Y-axis direction with the second antenna unit T2. The fourth antenna unit T4 is rotated 90 degrees counterclockwise compared to the third antenna unit T3 (that is, the fourth antenna unit T4 is rotated 270 degrees sequentially with the Z axis as the center compared to the first antenna unit T1) and is both arranged in an X-axis direction with the third antenna unit T3.

[0046] like Fig.10 Shown is an S parameter diagram of an antenna array with 2×2 antenna units, illustrating S11 (defined as the input reflection coefficient of the first feeding line 41 of the first antenna unit T1), corresponding S22 (defined as the output reflection coefficient of the second feeding line 42 of the first antenna unit T1), S12 (defined as the isolation between the first feeding line 41 of the first antenna unit T1 and the second feeding line 42 of the first antenna unit T1), the X-axis indicates two frequency bands TX (14~14.5GHz) and RX (10.7~12.7GHz), and the unit of the Y-axis is dB.

[0047] Fig.11 It is an antenna gain diagram, which is used to illustrate the gain of two frequency bands TX (14~14.5GHz) and RX (10.7~12.7GHz). Fig.12 : is an axial ratio diagram, where the vertical feed phase is set to 90 degrees and the horizontal feed phase is set to 0 degrees. Fig.13 It is the radiation pattern of the antenna, which is used to illustrate the situations where the frequencies are 10.75 GHz, 11.75 GHz, 12.75 GHz, 14 GHz, and 14.5 GHz respectively.

[0048] In summary, the above embodiments have the following advantages: 1. The coupling effect between the parasitic element and the radiator is used to expand the bandwidth, so as to achieve the purpose of integrating the transmitting frequency band and the receiving frequency band into the same antenna. 2. The dual feeding method of the first feeding line and the second feeding line designed on the fourth substrate can realize the characteristics of circular polarization, and the axial ratio can reach 0.02dB by using the antenna array design (see Fig.12In the frequency band of 10.7 GHz to 14.5 GHz). 3. The design of coupling the multi-layer structure from the first substrate to the fourth substrate and the first feeding line to the second feeding line is more conducive to achieving ultra-wideband.

[0049] The above is only a preferred embodiment of the present invention, and should not be used to limit the scope of the present invention. That is, any simple equivalent changes and modifications made according to the claims and description of the present invention are still within the scope of the present invention.

Claims

1. A dual-feed circularly polarized broadband antenna, characterized in that: Include: A substrate module includes a parasitic element and a radiator disposed under the parasitic element and at a first thickness from the parasitic element, wherein the center point of the parasitic element and the center point of the radiator are projected onto the same point along a first direction; a third substrate unit, stacked under the substrate module, and having a first slot and a second slot at a second thickness from the radiator; and a fourth substrate unit, stacked under the third substrate unit, and having a first feeding line and a second feeding line, the first feeding line being away from the first slot by a third thickness, and the second feeding line being away from the second slot by the third thickness; When operating in a transmission mode, a signal is electromagnetically induced from the first feeding line and the second feeding line to the first slot and the second slot respectively, and then electromagnetically induced from the first slot and the second slot to the radiator, and then electromagnetically induced from the radiator to the parasitic element, and an output electromagnetic wave is sent by the parasitic element; When operating in a receiving mode, an input electromagnetic wave from the external environment is received by the parasitic element and electromagnetically induced to the radiator, and then electromagnetically induced to the first slot and the second slot by the radiator, and then electromagnetically induced to the first feeding line and the second feeding line respectively.

2. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The substrate module further includes a first substrate and a second substrate. The first substrate has a first surface on which the parasitic element is disposed and a second surface. The second substrate has a first surface connected to the second surface of the first substrate and a second surface on which the radiator is disposed.

3. The dual-feed circularly polarized broadband antenna according to claim 2, characterized in that: The substrate module further includes a first adhesive layer, and the first adhesive layer is used to adhere the first substrate and the second substrate. The distance between the first surface of the first substrate and the second surface of the second substrate is close to the first thickness.

4. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The third substrate unit has a third substrate. The third substrate has a first surface and a second surface where the first slot hole and the second slot hole are arranged. The distance between the first surface and the second surface of the third substrate is close to the second thickness.

5. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The fourth substrate unit has a fourth substrate. The fourth substrate has a first surface and a second surface where the first feeding line and the second feeding line are arranged. The distance between the first surface and the second surface of the fourth substrate is close to the third thickness.

6. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The device also includes a second adhesive layer, and the second adhesive layer is used for bonding the third substrate unit and the substrate module.

7. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The device further comprises a third adhesive layer, and the third adhesive layer is used for bonding the third substrate unit and the fourth substrate unit.

8. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The parasitic element and the radiator are circular.

9. The dual-feed circularly polarized broadband antenna according to claim 1, characterized in that: The first slot is a horizontal dumbbell-shaped slot with two ends extending along a second direction, the second slot is a vertical dumbbell-shaped slot with two ends extending along a third direction, the first feed line is a vertical microstrip line extending along the second direction, and the second feed line is a horizontal microstrip line extending along the third direction.

10. An antenna array, characterized in that: Include: a first antenna unit; A second antenna unit, which is rotated 90 degrees counterclockwise compared to the first antenna unit and is disposed in an X-axis direction together with the first antenna unit; A third antenna unit, which is rotated 90 degrees counterclockwise compared to the second antenna unit and is disposed in a Y-axis direction together with the second antenna unit; a fourth antenna unit, which is rotated 90 degrees counterclockwise compared to the third antenna unit and is disposed in the X-axis direction together with the third antenna unit; Each of the first antenna unit to the fourth antenna unit comprises the dual-feed circularly polarized broadband antenna of claims 1 to 9.

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