CN110829010A - Dual-circularly-polarized-beam reconfigurable microstrip antenna - Google Patents

Abstract

The invention discloses a reconfigurable microstrip antenna for double circularly polarized beams, which comprises a first dielectric plate, a second dielectric plate, a first voltage control module, a second voltage control module, a third voltage control module and a fourth voltage control module; an air layer is arranged between the two dielectric plates; a copper-clad layer is arranged on the upper surface of the second dielectric plate; the copper-clad layer is provided with a circular patch, a first, a second, a third, a fourth, a fifth, a sixth, a seventh and an eight-sector parasitic patch, a first, a second, a third and a fourth variable capacitance diode, a first, a second, a third, a fourth, a fifth, a sixth, a seventh and an eight-patch inductor, a first, a second, a third, a fourth, a sixth, a seventh and an eight-patch inductor, a first, a second, a third, a,Five, six, seven and eight voltage control interfaces; the upper surface of the first dielectric plate is provided with a grounding plate with a cross coupling aperture, the lower surface of the first dielectric plate is provided with a copper-coated layer, the copper-coated layer is provided with a first coupling feeder, a second coupling feeder and a branch line directional coupler, and the copper-coated layers on the upper surface and the lower surface of the first dielectric plate are respectively provided with a first input port and a second input port. The invention can realize the beam scanning angle range of +/-20 degrees, and the beam scanning on +/-45-degree two surfaces and the reflection coefficient S₁₁Below-10 dB.

Description

A Dual Circularly Polarized Beam Reconfigurable Microstrip Antenna

technical field

The present invention relates to the technical field of antennas, in particular to a dual circularly polarized beam reconfigurable microstrip antenna.

Background technique

With the rapid development of wireless communication, there are higher requirements for the communication capacity and transmission rate of the system. Patch antennas are widely used in the design of front-end transmitting and receiving antennas for wireless communication systems due to their light weight, small size, easy conformality, easy processing, and low cost. With the wider application of 5G technology and the rapid growth of wireless communication users, there is an urgent need to make full use of spectrum resources within the division of limited spectrum resources, improve the utilization rate of spectrum resources, and thus improve the performance of wireless communication systems. One of the effective solutions to this need is beamforming, which is increasingly used in personal communication systems (PCS), satellite communication systems, wireless local loops, wireless local area networks (LANs), and wireless ATM systems. It is of great research significance to design circularly polarized beam reconfigurable antennas using microstrip antennas.

Investigate and understand existing technologies, as follows:

Professor Xiao Shaoqiu et al. designed a broadband circularly polarized multi-beam antenna array using Butler matrix, designed a Butler matrix based on broadband directional couplers and broadband phase shifters, and used broadband circularly polarized antennas to form a four-element antenna array. The antenna array uses a phase-shift network to achieve circularly polarized beamforming.

Prof. A. Khidre et al. proposed a design method for an electrically tunable multi-beam circularly polarized antenna. Load a varactor diode on the parasitic patch, and realize beam control by changing the capacitance value of the varactor diode and changing the characteristics of the parasitic unit.

In general, in the existing work, there are many researches on beam reconfigurable microstrip antennas, but many design methods are implemented by methods such as phase feeding networks, which are easy to cause energy loss, and the design is relatively complex. Therefore, it is of great significance to design a simple dual circularly polarized beam reconfigurable antenna.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art, and proposes a dual circularly polarized beam reconfigurable microstrip antenna. The operating frequency of the antenna is 2 GHz. By adjusting the capacitance value of the varactor diode, ± The beam scanning angle range of 20°, and the beam scanning on two planes of ±45°, during the whole adjustment process, the reflection coefficient S11 is basically kept below -10dB. The entire antenna structure is simple and compact, and the processing is convenient and the cost is low.

In order to achieve the above purpose, the technical solution provided by the present invention is: a dual circularly polarized beam reconfigurable microstrip antenna, comprising a first dielectric plate, a second dielectric plate, a first voltage control module, and a second voltage control module , a third voltage control module and a fourth voltage control module; the second dielectric plate is located above the first dielectric plate, and an air layer exists between the two dielectric plates to improve the gain of the antenna; the upper part of the second dielectric plate A copper-clad layer is formed on the surface, and the copper-clad layer is respectively provided with a circular patch, a first fan-shaped parasitic patch, a second fan-shaped parasitic patch, a third fan-shaped parasitic patch, a fourth fan-shaped parasitic patch, and a third fan-shaped parasitic patch. Five sector parasitic patch, sixth sector parasitic patch, seventh sector parasitic patch, eighth sector parasitic patch, first varactor diode, second varactor diode, third varactor diode, fourth varactor diode , the first chip inductor, the second chip inductor, the third chip inductor, the fourth chip inductor, the fifth chip inductor, the sixth chip inductor, the seventh chip inductor, the eighth chip inductor, the first chip inductor a voltage control interface, a second voltage control interface, a third voltage control interface, a fourth voltage control interface, a fifth voltage control interface, a sixth voltage control interface, a seventh voltage control interface, and an eighth voltage control interface; the circle The first fan-shaped parasitic patch and the second fan-shaped parasitic patch are connected by the first varactor diode to form a parasitic unit, and about the first fan-shaped parasitic patch The varactor diode is symmetrical; the third sector-shaped parasitic patch and the fourth sector-shaped parasitic patch are connected by the second varactor diode to form a parasitic unit, and are symmetrical with respect to the second varactor diode; the fifth sector-shaped parasitic patch and The sixth fan-shaped parasitic patch is connected by the third varactor diode to form a parasitic unit, and is symmetrical with respect to the third varactor diode; the seventh fan-shaped parasitic patch and the eighth fan-shaped parasitic patch are formed by connecting the fourth varactor diode A parasitic unit, which is symmetrical with respect to the fourth varactor diode; the above-mentioned four parasitic units are evenly distributed around the circular patch, are on the same circumference, and have the same center as the circular patch, and two parasitic units are about the circular patch The symmetry axis of the patch is mirror-symmetrical. The center point of the varactor diode is at the ±45° intersection line through the center of the circular patch. By adjusting the capacitance value of the varactor diode, the current distribution generated by the four parasitic units can be made. The first fan-shaped parasitic patch is connected to the first voltage control interface through the first patch inductance, and the second fan-shaped parasitic patch is connected to the second voltage through the second patch inductance. The control interface is connected, the first voltage control interface and the second voltage control interface are respectively connected with the first voltage control module, the third fan-shaped parasitic patch is connected with the third voltage control interface through the third patch inductance, the The fourth fan-shaped parasitic patch is connected to the fourth voltage control interface through the fourth patch inductance, the third voltage control interface and the fourth voltage control interface are respectively connected to the second voltage control module, and the fifth fan-shaped parasitic patch The fifth patch inductance is connected to the fifth voltage control interface, and the sixth fan-shaped parasitic patch is electrically connected through the sixth patch. The inductor is connected to the sixth voltage control interface, the fifth voltage control interface and the sixth voltage control interface are respectively connected to the third voltage control module, and the seventh fan-shaped parasitic patch is connected to the seventh voltage control module through the seventh patch inductance interface connection, the eighth fan-shaped parasitic patch is connected to the eighth voltage control interface through the eighth patch inductance, the seventh voltage control interface and the eighth voltage control interface are respectively connected to the fourth voltage control module, wherein the above The role of the chip inductor is to block the current of the fan-shaped parasitic patch from entering the voltage control module through the voltage control interface; the upper surface of the first dielectric plate is provided with a grounding plate, and the lower surface is formed with a copper clad layer, the grounding plate There is a cross coupling aperture on it, and the copper clad layer on the lower surface of the first dielectric plate is respectively provided with a first coupling feeder, a second coupling feeder and a branch line directional coupler for providing a signal with a phase difference of ±90°, And a first input port and a second input port are respectively made on the copper clad layers on the upper surface and the lower surface of the first dielectric board, and the first coupling feeder is connected to the first input port through a branch line directional coupler, Feeding through the first input port can realize right-hand circular polarization, the second coupled feeder is connected to the second input port through a branch line directional coupler, and feeding through the second input port can realize left-hand circular polarization. The energy fed by the first input port and the second input port is finally coupled to the circular patch through the cross coupling aperture.

Further, the size and material of the first medium plate and the second medium plate are the same.

Further, the cross coupling aperture is located just below the circular patch.

Further, the branch line directional coupler is a 3dB/90° directional coupler, and its input and output ports are all 50 ohm impedance matching.

Further, the electrical lengths of the first coupled feeder and the second coupled feeder are the same.

Further, the first input port and the second input port are both 50 ohm impedance matching ports.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The working frequency of the antenna of the present invention is 2GHz, and the beam scanning angle transformation of ±20° can be realized by adjusting the two ends of the varactor diode, and the angle transformation can be realized in two planes of ±45°.

2. The antenna of the present invention can keep the reflection coefficient S ₁₁ below -10dB while changing the beam direction.

3. The antenna of the present invention can realize two polarization modes: left-handed polarization and right-handed polarization.

4. The antenna of the present invention is simple to process, light in weight, and has a good application prospect.

Description of drawings

FIG. 1 is a perspective view of a dual circularly polarized beam reconfigurable microstrip antenna of the present invention.

FIG. 2 is a side view of the dual circularly polarized beam reconfigurable microstrip antenna of the present invention.

FIG. 3 is a top view of the dual circularly polarized beam reconfigurable microstrip antenna of the present invention.

FIG. 4 is a bottom view of the dual circularly polarized beam reconfigurable microstrip antenna of the present invention.

FIG. 5 is a diagram showing the simulation results of S ₁₁ and S ₂₂ of the dual circularly polarized beam reconfigurable microstrip antenna of the present invention.

Fig. 6 is the beam direction simulation result diagram of the dual circularly polarized beam reconfigurable microstrip antenna of the present invention; in the figure, (a) is the +45° plane left-handed circular polarization, (b) is the +45° plane right-handed Circular polarization, (c) is left-handed circular polarization in the -45° plane, and (d) is right-handed circular polarization in the -45° plane.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments.

Referring to FIG. 1 to FIG. 4 , the dual circularly polarized beam reconfigurable microstrip antenna provided in this embodiment includes a first dielectric plate 1 , a second dielectric plate 2 , a first voltage control module M1 , and a second voltage control module M1 . The control module M2, the third voltage control module M3 and the fourth voltage control module M4; the second dielectric plate 2 is located above the first dielectric plate 1, and an air layer 6 exists between the two dielectric plates. The main function of the air layer 6 is to In order to improve the gain of the antenna; a copper clad layer 5 is formed on the upper surface of the second dielectric plate 2, and the copper clad layer 5 is respectively provided with a circular patch 7, a first fan-shaped parasitic patch 8, a second fan-shaped patch Parasitic patch 9, third sector parasitic patch 10, fourth sector parasitic patch 11, fifth sector parasitic patch 12, sixth sector parasitic patch 13, seventh sector parasitic patch 14, eighth sector parasitic patch Sheet 15, first varactor diode C1, second varactor diode C2, third varactor diode C3, fourth varactor diode C4, first chip inductor L1, second chip inductor L2, third chip inductor L3, fourth chip inductor L4, fifth chip inductor L5, sixth chip inductor L6, seventh chip inductor L7, eighth chip inductor L8, first voltage control interface 16, second voltage control interface 17 , the third voltage control interface 18, the fourth voltage control interface 19, the fifth voltage control interface 20, the sixth voltage control interface 21, the seventh voltage control interface 22, the eighth voltage control interface 23; the circular patch 7 It is located in the middle position of the copper clad layer 5 as the main radiation source of the whole antenna; the first fan-shaped parasitic patch 8 and the second fan-shaped parasitic patch 9 are connected through the first varactor diode C1 to form a parasitic unit, and about the first A varactor diode C1 is symmetrical; the third sector-shaped parasitic patch 10 and the fourth sector-shaped parasitic patch 11 are connected to form a parasitic unit through the second varactor diode C2, and are symmetrical with respect to the second varactor diode C2; The five-sector parasitic patch 12 and the sixth sector-shaped parasitic patch 13 are connected by the third varactor diode C3 to form a parasitic unit, and are symmetrical with respect to the third varactor diode C3; the seventh sector-shaped parasitic patch 14 and the eighth sector-shaped parasitic patch 14 The parasitic patch 15 is connected by the fourth varactor diode C4 to form a parasitic unit, and is symmetrical about the fourth varactor diode C4; the above-mentioned four parasitic units are evenly distributed around the circular patch 7, and are on the same circumference, and The circular patch 7 has the same center of the circle, and the two parasitic units are mirror-symmetrical about the symmetry axis of the circular patch 7. The center point of the varactor diode is at the ±45° intersection line through the center of the circular patch. The capacitance value of the varactor diode can make the current distribution generated by the four parasitic units different, so as to realize the control of the beam direction; the first fan-shaped parasitic patch 8 communicates with the first voltage control interface 16 through the first patch inductance L1 The second fan-shaped parasitic patch 9 is connected to the second voltage control interface 17 through the second patch inductance L2, and the first voltage control interface 16 and the second voltage control interface 17 are respectively connected with the first voltage control module M1 connection, the third fan-shaped parasitic patch 10 pass It is connected to the third voltage control interface 18 through the third chip inductor L3, the fourth fan-shaped parasitic patch 11 is connected to the fourth voltage control interface 19 through the fourth chip inductor L4, and the third voltage control interface 18 and The fourth voltage control interface 19 is respectively connected to the second voltage control module M2, the fifth fan-shaped parasitic patch 12 is connected to the fifth voltage control interface 20 through the fifth patch inductance L5, and the sixth fan-shaped parasitic patch 13 The sixth voltage control interface 21 is connected to the sixth voltage control interface 21 through the sixth chip inductor L6, the fifth voltage control interface 20 and the sixth voltage control interface 21 are respectively connected to the third voltage control module M3, and the seventh fan-shaped parasitic patch 14 The seventh patch inductor L7 is connected to the seventh voltage control interface 22, the eighth sector-shaped parasitic patch 15 is connected to the eighth voltage control interface 23 through the eighth patch inductor L8, and the seventh voltage control interface 22 and The eighth voltage control interface 23 is respectively connected with the fourth voltage control module M4, wherein, the function of the above-mentioned chip inductor is to block the current of the fan-shaped parasitic chip from entering the voltage control module through the voltage control interface; A grounding plate 4 is arranged on the upper surface, a copper cladding layer 3 is formed on the lower surface, a cross coupling aperture 24 is arranged on the grounding plate 4, and the copper cladding layer 3 on the lower surface of the first dielectric plate 1 is respectively provided with a second A coupling feeder 25 , a second coupling feeder 26 and a branch line directional coupler 27 for providing a signal with a phase difference of ±90°, and the copper clad layers 3 on the upper surface and the lower surface of the first dielectric board 1 are respectively A first input port 28 and a second input port 29 are made, the first coupling feeder 25 is connected to the first input port 28 through the branch line directional coupler 27, and feeding through the first input port 28 can realize a right-handed circle Polarization, the second coupled feeder 26 is connected to the second input port 29 through the branch line directional coupler 27, the feeder through the second input port 29 can realize left-handed circular polarization, from the first input port 28 and the second input The energy fed by the port 29 is finally coupled to the circular patch 7 through the cross coupling aperture 24 .

In the design, the dielectric constants of the first dielectric plate 1 and the second dielectric plate 2 are both 2.55, and the loss tangent is 0.0029. The thickness of the first dielectric plate 1 and the second dielectric plate 2 are both 0.8 mm; the thickness of the air layer 6 is 2 mm. The fan-shaped parasitic patch length is valued around one quarter of the wavelength of the designed frequency. The values of the chip inductors are all 270nH. The cross coupling aperture 24 is located directly below the circular patch 7 . The electrical lengths of the first coupled feeder 25 and the second coupled feeder 26 are the same. The branch line directional coupler 27 is a 3dB/90° directional coupler whose input and output ports are both 50 ohm impedance matching, and is used to realize an input signal with a phase difference of ±90°. Both the first input port 28 and the second input port 29 are impedance matching ports of 50 ohms.

Referring to FIG. 5 , the simulation results of S ₁₁ and S ₂₂ of the above-mentioned dual circularly polarized beam reconfigurable microstrip antenna in this embodiment are shown. It can be seen from the figure that when changing different capacitance values, the characteristics of the reflection coefficient are basically not changed, and the reflection coefficient remains below -10dB.

Referring to FIG. 6 , the simulation result of the beam direction of the above-mentioned dual circularly polarized beam reconfigurable microstrip antenna in this embodiment is shown. It can be seen from the figure that the beam direction can be changed from -20° to +20° by setting different capacitance values, and the +45° surface is composed of the first and third varactors C1 and C3 and the circular patch 7 and three. A plane perpendicular to the dielectric plate where the center points are located; the -45° plane is a plane perpendicular to the dielectric plate where the center points of the second and fourth varactors C2, C4 and the circular patch 7 are located.

The above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention. Therefore, any changes made according to the shape and principle of the present invention should be included within the protection scope of the present invention.

Claims (6)

1. A dual circularly polarized beam reconfigurable microstrip antenna is characterized in that: comprising a first dielectric plate, a second dielectric plate, a first voltage control module, a second voltage control module, a third voltage control module and a Four voltage control modules; the second dielectric board is located above the first dielectric board, and there is an air layer between the two dielectric boards to improve the gain of the antenna; the upper surface of the second dielectric board is formed with a copper clad layer, so The copper-clad layer is respectively provided with a circular patch, a first fan-shaped parasitic patch, a second fan-shaped parasitic patch, a third fan-shaped parasitic patch, a fourth fan-shaped parasitic patch, a fifth fan-shaped parasitic patch, and a sixth fan-shaped parasitic patch. Sector parasitic patch, seventh sector parasitic patch, eighth sector parasitic patch, first varactor diode, second varactor diode, third varactor diode, fourth varactor diode, first patch inductor, first The second chip inductor, the third chip inductor, the fourth chip inductor, the fifth chip inductor, the sixth chip inductor, the seventh chip inductor, the eighth chip inductor, the first voltage control interface, the second voltage control interface, third voltage control interface, fourth voltage control interface, fifth voltage control interface, sixth voltage control interface, seventh voltage control interface, eighth voltage control interface; the circular patch is located on the copper clad layer The middle position is used as the main radiation source of the whole antenna; the first fan-shaped parasitic patch and the second fan-shaped parasitic patch are connected by the first varactor diode to form a parasitic unit, and are symmetrical with respect to the first varactor diode; The third fan-shaped parasitic patch and the fourth fan-shaped parasitic patch are connected through the second varactor diode to form a parasitic unit, and are symmetrical with respect to the second varactor diode; the fifth and sixth sector-shaped parasitic patches are connected by the third Three varactors are connected to form a parasitic unit, and are symmetrical with respect to the third varactor; the seventh fan-shaped parasitic patch and the eighth fan-shaped parasitic patch are connected by the fourth varactor to form a parasitic unit, and are about the fourth The varactor diode is symmetrical; the above four parasitic units are evenly distributed around the circular patch, are on the same circumference, and have the same center as the circular patch, and the two parasitic units are mirror-symmetrical about the symmetry axis of the circular patch , the center point of the varactor diode is at the position of the ±45° intersection line passing through the center of the circular patch. By adjusting the capacitance value of the varactor diode, the current distribution generated by the four parasitic units can be different, so as to realize the beam direction. control; the first fan-shaped parasitic patch is connected to the first voltage control interface through the first patch inductance, the second fan-shaped parasitic patch is connected to the second voltage control interface through the second patch inductance, and the first The voltage control interface and the second voltage control interface are respectively connected to the first voltage control module, the third fan-shaped parasitic patch is connected to the third voltage control interface through the third patch inductance, and the fourth fan-shaped parasitic patch is connected to the third voltage control interface through the third patch inductance. The four chip inductors are connected to the fourth voltage control interface, the third voltage control interface and the fourth voltage control interface are respectively connected to the second voltage control module, and the fifth fan-shaped parasitic chip is connected to the third voltage control module through the fifth chip inductor. Five voltage control interfaces are connected, and the sixth sector-shaped parasitic patch is connected to the sixth voltage control interface through the sixth patch inductance, The fifth voltage control interface and the sixth voltage control interface are respectively connected to the third voltage control module, the seventh sector-shaped parasitic patch is connected to the seventh voltage control interface through the seventh patch inductance, and the eighth sector-shaped parasitic patch is connected to the seventh voltage control interface. The patch is connected to the eighth voltage control interface through the eighth patch inductance, and the seventh voltage control interface and the eighth voltage control interface are respectively connected to the fourth voltage control module, wherein the function of the above-mentioned patch inductance is to block the sector The current of the parasitic patch enters the voltage control module through the voltage control interface; the upper surface of the first dielectric plate is provided with a ground plate, the lower surface is formed with a copper clad layer, the ground plate is provided with a cross coupling aperture, the A first coupling feeder, a second coupling feeder and a branch line directional coupler for providing a signal with a phase difference of ±90° are respectively provided on the copper clad layer on the lower surface of the first dielectric board, and the first dielectric board A first input port and a second input port are respectively made on the copper clad layer on the surface and the lower surface, the first coupling feeder is connected to the first input port through the branch line directional coupler, and feeding through the first input port can Realize right-handed circular polarization, the second coupling feeder is connected to the second input port through the branch line directional coupler, and the feeder through the second input port can realize left-handed circular polarization, from the first input port and the second input port. The fed energy is finally coupled to the circular patch through the cross coupling aperture. 2 . The dual circularly polarized beam reconfigurable microstrip antenna according to claim 1 , wherein the size and material of the first dielectric plate and the second dielectric plate are the same. 3 . 3 . The dual circularly polarized beam reconfigurable microstrip antenna according to claim 1 , wherein the cross coupling aperture is located directly below the circular patch. 4 . 4. a kind of dual circularly polarized beam reconfigurable microstrip antenna according to claim 1, is characterized in that: described branch line directional coupler is 3dB/90 ° directional coupler, and its input and output ports are both 50 Ohmic impedance matching. 5 . The dual circularly polarized beam reconfigurable microstrip antenna according to claim 1 , wherein the electrical lengths of the first coupling feeder and the second coupling feeder are the same. 6 . 6 . The dual circularly polarized beam reconfigurable microstrip antenna according to claim 1 , wherein the first input port and the second input port are both 50 ohm impedance matching ports. 7 .

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