A dual-polarization ultra-wideband Yagi antenna

Abstract

The present invention discloses a dual-polarization ultra-wideband Yagi antenna, comprising: a coaxial cable, a radiation vibrator, a reflector, a metal column and a plurality of directors; the reflector is arranged at the bottom of the coaxial cable and the metal column, the radiation vibrator is arranged on the metal column above the reflector, and is also arranged on the top of the coaxial cable; the plurality of directors are arranged in parallel on the metal column above the radiation vibrator at preset intervals. In the embodiment of the present invention, by setting the size of the reflector to be larger than the size of the radiation vibrator, when part of the electromagnetic wave generated on the radiation vibrator is radiated toward the reflector, the electromagnetic wave can be reflected to the radiation vibrator through the reflector, thereby making most of the electromagnetic waves radiate toward the director direction, which is beneficial to improving the radiation directivity of the Yagi antenna and improving the signal transmission speed of the Yagi antenna, so that it is suitable for modern mobile communications.

Description

Technical Field

[0001] The present invention relates to the technical field of communication equipment, and in particular to a dual-polarization ultra-wideband Yagi antenna. Background Art

[0002] The Yagi antenna is usually an end-fire antenna composed of an active vibrator, a passive reflector and several passive directors arranged in parallel. The Yagi antenna is widely used in radar, direction finding, communication and other fields due to its simple structure, easy manufacturing, low cost and strong directivity of its radiation pattern. In order to improve the anti-interference ability of the system and reduce the number of antennas, mobile communications now usually use dual polarization to improve diversity gain and use multi-standard wideband antennas. The existing Yagi antenna is usually a single-polarization narrow-band antenna, which results in a low signal transmission speed of the existing Yagi antenna, making it difficult to apply it to modern mobile communications. Summary of the invention

[0003] The invention provides a dual-polarization ultra-wideband Yagi antenna to solve the technical problem that the existing Yagi antenna has a low signal transmission speed and is difficult to be applied to modern mobile communications.

[0004] An embodiment of the present invention provides a dual-polarization ultra-wideband Yagi antenna, comprising:

[0005] Coaxial cable, radiating oscillator, reflecting plate, metal column and several directors;

[0006] The reflecting plate is arranged at the bottom ends of the coaxial cable and the metal column, the radiating vibrator is arranged on the metal column above the reflecting plate and at the same time on the top end of the coaxial cable; a plurality of the directors are arranged in parallel at preset intervals on the metal column above the radiating vibrator.

[0007] Furthermore, a circular ring line is provided on the outer surface of the director, the circumference of the outer ring line of the circular ring line is greater than the circumference of the inner ring line of the circular ring line, and the circumferences of the lines of different lengths correspond to resonance points of different frequencies, so that the dual-polarization ultra-wideband Yagi antenna has two resonance points of different frequencies.

[0008] Furthermore, the distance between the director close to the radiating oscillator and the radiating oscillator is 0.15λ f0 The distance between two adjacent directors is 0.2λ f0 , where λ f0 is the wavelength corresponding to the center frequency.

[0009] Furthermore, the coaxial cable includes a first cable line and a second cable line arranged in parallel, the metal column includes a first metal column opposite to the first cable line and a second metal column opposite to the second cable line, the first cable line and the first metal column constitute a first feeding balun, and the second cable line and the second metal column constitute a second feeding balun.

[0010] Further, the radiating vibrator is provided with four radiating vibrator arms, including: a first radiating vibrator arm, a second radiating vibrator arm, a third radiating vibrator arm and a fourth radiating vibrator arm, and each of the radiating vibrator arms is provided with a corresponding top layer line, and a central line is provided at the center of the radiating vibrator;

[0011] The outer conductor of the first cable is connected to the first radiation dipole arm, and the inner conductor of the first cable is connected to the top layer line on the first radiation dipole arm;

[0012] The outer conductor of the second cable is connected to the third radiation dipole arm. The outer conductor of the second cable is connected to the third radiation dipole arm.

[0013] Furthermore, the bottom layer of the radiation oscillator is provided with a plurality of bottom layer circuits.

[0014] Furthermore, the radiation oscillator is a high-frequency dielectric plate clad with copper on both sides, the director is a dielectric plate clad with copper on one side, and the reflection plate is a metal plate.

[0015] In the embodiment of the present invention, the size of the reflector is set to be larger than the size of the radiating vibrator. When part of the electromagnetic wave generated on the radiating vibrator radiates toward the reflector, the electromagnetic wave can be reflected to the radiating vibrator by the reflector, thereby making most of the electromagnetic waves radiate in the direction of the director, which is beneficial to improving the directivity of the Yagi antenna radiation and improving the signal transmission speed of the Yagi antenna. The circumferences of the circular loop lines in the director of the embodiment of the present invention are not equal, so that the antenna has two resonance points of different frequencies, thereby effectively expanding the working bandwidth of the radiating vibrator and further improving the transmission speed of the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 1 is a schematic structural diagram of a dual-polarization ultra-wideband Yagi antenna provided by an embodiment of the present invention;

[0017] Figure 2 It is a schematic structural diagram of a coaxial cable and a radiating oscillator provided in an embodiment of the present invention;

[0018] Figure 3 It is a schematic diagram of the top-layer circuit of the radiation oscillator provided in an embodiment of the present invention;

[0019] Figure 4It is a schematic diagram of the bottom layer circuit of the radiation oscillator provided in an embodiment of the present invention;

[0020] Figure 5 is a schematic diagram of the structure of a director provided by an embodiment of the present invention;

[0021] Figure 6 is a schematic diagram of antenna polarization isolation provided by an embodiment of the present invention;

[0022] Figure 7 It is a schematic diagram of the return loss of the antenna provided in an embodiment of the present invention.

[0023] The reference numerals in the accompanying drawings of the specification are as follows:

[0024] 1. Coaxial cable; 101. First cable line; 102. Second cable line; 2. Radiating oscillator; 201. First radiating oscillator arm; 202. Second radiating oscillator arm; 203. Third radiating oscillator arm; 204. Fourth radiating oscillator arm; 210. Center line; 220. Medium; 211. First top-layer line; 212. Second top-layer line; 213. Third top-layer line; 214. Fourth top-layer line; 3. Director; 301. Inner ring line; 302. Outer ring line; 4. Reflector; 5. Metal column; 501. First metal column; 502. Second metal column. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] See also Figure 1 , an embodiment of the present invention provides a dual-polarization ultra-wideband Yagi antenna, comprising:

[0029] Coaxial cable 1, radiating oscillator 2, reflecting plate 4, metal column 5 and several directors 3;

[0030] The reflector 4 is arranged at the bottom of the coaxial cable 1 and the metal column 5, and the radiation vibrator 2 is arranged on the metal column 5 above the reflector 4 and at the same time on the top of the coaxial cable 1; a plurality of directors 3 are arranged in parallel on the metal column 5 above the radiation vibrator 2 at a preset interval;

[0031] The size of the reflection plate 4 is larger than that of the radiation vibrator 2 .

[0032] In the embodiment of the present invention, when the radio frequency signal is transmitted to the radiation oscillator 2 through the coaxial cable 1, the radio frequency signal resonates on the radiation oscillator 2 and excites an electromagnetic field. A part of the electromagnetic field is coupled to the first director 3 closest to the radiation oscillator 2. When the line circumference of the first director 3 is equivalent to the corresponding electromagnetic wave wavelength, the line of the first director 3 will generate an induced current. After the line resonates, the induced current generates an electromagnetic field that is coupled to the next director 3 (the second director). Similarly, a part of the electromagnetic field generated by the second director is coupled to the next director 3. Part of the electromagnetic wave generated on the radiation oscillator 2 is radiated to the reflector 4. By setting the size of the reflector 4 to be larger than the size of the radiation oscillator 2, the electromagnetic wave can be reflected to the radiation oscillator 2 through the reflector 4, so that most of the electromagnetic waves are radiated in the direction of the director 3, which is conducive to improving the radiation directivity of the Yagi antenna and improving the signal transmission speed of the Yagi antenna.

[0033] See also Figure 5 In one embodiment, a circular ring line is provided on the outer surface of the director 3, and the circumference of the outer ring line 302 of the circular ring line is greater than the circumference of the inner ring line 301 of the circular ring line. The circumferences of the lines of different lengths correspond to resonance points of different frequencies, so that the dual-polarization ultra-wideband Yagi antenna has two resonance points of different frequencies.

[0034] In an embodiment of the present invention, the circumference of the outer loop line 302 of the circular loop is greater than the circumference of the inner loop line 301 of the circular loop, that is, the wavelength of the resonant electromagnetic wave corresponding to the outer loop line 302 is greater than the wavelength of the electromagnetic wave corresponding to the inner loop line 301, that is, the resonant frequency corresponding to the outer loop line 302 is lower than the resonant frequency corresponding to the inner loop line 301, so that the Yagi antenna of the embodiment of the present invention has two resonance points of different frequencies, effectively expanding the working bandwidth of the radiation oscillator 2.

[0035] Optionally, the line arranged on the surface of the director 3 can be a circular line, a square line, etc., and the circumference of the line corresponds to the operating frequency of the radiation oscillator 2.

[0036] In one embodiment, the distance between the director 3 close to the radiating vibrator 2 and the radiating vibrator 2 is 0.15λ f0 , the distance between two adjacent directors 3 is 0.2λ f0 , where λ f0 is the wavelength corresponding to the center frequency.

[0037] In the embodiment of the present invention, the distance between two adjacent directors 3 can be adjusted according to actual needs, and the intervals between them can be the same or different.

[0038] See also Figure 2 The coaxial cable 1 includes a first cable line 101 and a second cable line 102 arranged in parallel, a first metal column 501 opposite to the first cable line 101 and a second metal column 502 opposite to the second cable line 102, the first cable line 101 and the first metal column 501 constitute a first feeding balun, and the second cable line 102 and the second metal column 502 constitute a second feeding balun.

[0039] In the embodiment of the present invention, the first feeding balun and the second feeding balun are placed orthogonally to each other to form electromagnetic waves with orthogonal polarization. Optionally, the first feeding balun and the second feeding balun of the radiating oscillator 2 and the outer conductor of the coaxial cable 1 in the embodiment of the present invention are connected together by a reflector 4, and the first metal column 501 and the second metal column 503 are used to support the director 3, so that the structure of the director 3 is stable.

[0040] See also Figure 3-4 , the radiation oscillator 2 is provided with four radiation oscillator arms, including: a first radiation oscillator arm 201, a second radiation oscillator arm 202, a third radiation oscillator arm 203 and a fourth radiation oscillator arm 204, and each radiation oscillator arm is provided with a corresponding top layer line, and a central line 210 is provided at the center of the radiation oscillator 2;

[0041] It should be noted that the first radiation dipole arm 201 corresponds to the first top-layer line 211 , the second radiation dipole arm 202 corresponds to the second top-layer line 212 , the third radiation dipole arm 203 corresponds to the third top-layer line 213 , and the fourth radiation dipole arm 204 corresponds to the fourth top-layer line 214 .

[0042] The outer conductor of the first cable 101 is connected to the first radiation dipole arm 201 , and the inner conductor of the first cable 101 is connected to the top layer line on the first radiation dipole arm 201 ;

[0043] In the embodiment of the present invention, the outer conductor of the first cable 101 is connected to a preset position on the first radiation oscillator 2 by welding, and the inner conductor of the first cable 101 passes through the medium 220 in the radiation oscillator 2 and is welded to the top-layer line on the first radiation oscillator arm 201. When the RF signal is injected, the RF signal is transmitted along the second top-layer line 212, transmitted to the center line 210 through the metal hole, and transmitted to the third top-layer line 213 through the metal hole at the other end. It should be noted that the RF signal is coupled to the second radiation oscillator arm 202 in the third top-layer line 213.

[0044] The outer conductor of the second cable 102 is connected to the third radiation dipole arm 203 . The outer conductor of the second cable 102 is connected to the third radiation dipole arm 203 .

[0045] In an embodiment of the present invention, the outer conductor of the second cable 102 is connected to a preset position on the third radiation dipole arm 203 by welding, the inner conductor of the second cable 102 passes through the medium 220 in the radiation dipole 2 and is welded to the third top-layer line 213, and the RF signal is transmitted to the fourth radiation dipole arm 204 along the fourth top-layer line 214.

[0046] In one embodiment, the bottom layer of the radiation oscillator 2 is provided with a plurality of bottom layer lines.

[0047] In one embodiment, the radiation oscillator 2 is a high-frequency dielectric 220 plate with copper clad on both sides, the director 3 is a dielectric 220 plate with copper clad on one side, and the reflection plate 4 is a metal plate.

[0048] In the embodiment of the present invention, a metal circuit is printed on the radiation oscillator 2, and the reflector 4 is a metal plate, which can not only reflect electromagnetic waves but also effectively fix the antenna structure, thereby improving the stability of the antenna.

[0049] See also Figure 6, which is a schematic diagram of the polarization isolation of the antenna provided in the embodiment of the present invention. The Yagi antenna provided in the embodiment of the present invention has a standing wave ratio of less than 1.5 in the frequency band of 1.7GHz-2.7GHz and a relative bandwidth of 45.6% while ensuring that the radiation pattern meets the requirements. The isolation of the two input ports of the dual polarization is greater than 30dB, and the cross-polarization ratio is greater than 15dB. It has excellent performance and can well meet the requirements of modern mobile communications.

[0050] The implementation of the embodiments of the present invention has the following beneficial effects:

[0051] In the embodiment of the present invention, the size of the reflector 4 is set to be larger than the size of the radiating vibrator 2. When part of the electromagnetic wave generated on the radiating vibrator 2 is radiated toward the reflector 4, the electromagnetic wave can be reflected to the radiating vibrator 2 by the reflector 4, thereby making most of the electromagnetic waves radiate toward the director 3, which is beneficial to improving the directivity of the Yagi antenna radiation and improving the signal transmission speed of the Yagi antenna. The circumferences of the circular loop lines in the director 3 of the embodiment of the present invention are not equal, so that the antenna has two resonance points of different frequencies, thereby effectively expanding the working bandwidth of the radiating vibrator 2 and further improving the transmission speed of the antenna.

[0052] The above are preferred embodiments of the present invention. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A dual-polarization ultra-wideband Yagi antenna, characterized in that: include: Coaxial cable, radiating oscillator, reflecting plate, metal column and several directors; The reflector is arranged at the bottom of the coaxial cable and the metal column, the radiation vibrator is arranged on the metal column above the reflector, and is also arranged on the top of the coaxial cable; a plurality of directors are arranged in parallel on the metal column above the radiation vibrator at a preset interval; a plurality of bottom-layer lines are arranged at the bottom layer of the radiation vibrator; The size of the reflector is larger than that of the radiation vibrator; A circular ring line is arranged on the outer surface of the director, the circumference of the outer ring line of the circular ring line is greater than the circumference of the inner ring line of the circular ring line, and the circumferences of the lines of different lengths correspond to resonance points of different frequencies, so that the dual-polarization ultra-wideband Yagi antenna has two resonance points of different frequencies.

2. The dual-polarization ultra-wideband Yagi antenna according to claim 1, characterized in that: The distance between the director close to the radiating vibrator and the radiating vibrator is 0.15λ f0 The distance between two adjacent directors is 0.2λ f0 , where λ f0 is the wavelength corresponding to the center frequency.

3. The dual-polarization ultra-wideband Yagi antenna according to claim 1, characterized in that: The coaxial cable includes a first cable line and a second cable line arranged in parallel, the metal column includes a first metal column opposite to the first cable line and a second metal column opposite to the second cable line, the first cable line and the first metal column constitute a first feeding balun, and the second cable line and the second metal column constitute a second feeding balun.

4. The dual-polarization ultra-wideband Yagi antenna according to claim 3, characterized in that: The radiating vibrator is provided with four radiating vibrator arms, including: a first radiating vibrator arm, a second radiating vibrator arm, a third radiating vibrator arm and a fourth radiating vibrator arm, and each of the radiating vibrator arms is provided with a corresponding top layer circuit, and a central circuit is provided at the center of the radiating vibrator; The outer conductor of the first cable is connected to the first radiation dipole arm, and the inner conductor of the first cable is connected to the top layer line on the first radiation dipole arm; The outer conductor of the second cable is connected to the third radiation dipole arm.

5. The dual-polarization ultra-wideband Yagi antenna according to claim 1, characterized in that: The radiation oscillator is a high-frequency dielectric plate with copper clad on both sides, the director is a dielectric plate with copper clad on one side, and the reflection plate is a metal plate.

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