WO2015062545A1 - Antenna dipole unit with an asymmetric dipole - Google Patents

Antenna dipole unit with an asymmetric dipole Download PDF

Info

Publication number
WO2015062545A1
WO2015062545A1 PCT/CN2014/090102 CN2014090102W WO2015062545A1 WO 2015062545 A1 WO2015062545 A1 WO 2015062545A1 CN 2014090102 W CN2014090102 W CN 2014090102W WO 2015062545 A1 WO2015062545 A1 WO 2015062545A1
Authority
WO
WIPO (PCT)
Prior art keywords
dipole
dipole arm
arm
electrical length
antenna
Prior art date
Application number
PCT/CN2014/090102
Other languages
French (fr)
Inventor
Jinju Wang
Yaohuan LI
Original Assignee
Alcatel-Lucent Shanghai Bell Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alcatel-Lucent Shanghai Bell Co., Ltd. filed Critical Alcatel-Lucent Shanghai Bell Co., Ltd.
Publication of WO2015062545A1 publication Critical patent/WO2015062545A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/061—Two dimensional planar arrays
    • H01Q21/062—Two dimensional planar arrays using dipole aerials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00—Antenna arrays or systems
    • H01Q21/24—Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q25/00—Antennas or antenna systems providing at least two radiating patterns
    • H01Q25/001—Crossed polarisation dual antennas

Definitions

  • the present disclosure relates to wireless communication field, and particularly to an antenna dipole unit with an asymmetric dipole.
  • Fig. 1 shows a dual polarization base station antenna unit in prior art, which makes up an array and forms a polarization antenna array, which is orthogonal with each other in +45°and -45°direction polarization.
  • This polarization antenna array works at a receiving mode and a transmitting mode simultaneously.
  • the base station antenna consists of dipole group array. Each dipole includes four dipole arms 11, 12, 13 and 14.Two of the four dipole arms work with a +45°polarization direction, and the other two dipole arms work with a -45°polarization direction.
  • the lengths of those four dipole arms are same, and the shapes thereof are same, too.
  • azimuth patterns are as symmetric as possible get better cell capacity, to minimize unwanted scattered radiation from one cell to the other and to improve the effect of cell vesture.
  • the other key reason for the design and use of antenna array with symmetric azimuth patterns is that the cross polarization discrimination (XPD) will rise with improved symmetry.
  • Fig. 1 shows an example of the symmetric antenna dipole art in prior art.
  • the pattern in horizontal plane of the array composed by these symmetric dipoles will be asymmetric, because of the unbalanced feed of dipole. This will result in low cross polarization discrimination.
  • Fig. 2a shows an array which applies fences and a symmetric antenna dipole unit in prior art. While the symmetry can be realized effectively by using the fences 21, the antenna system will have following drawbacks after using the fences 21: (1) The fences 21 impact the VSWR of dipole 22 creating some impedance mismatch and worsening the whole antenna array VSWR; (2) The fences 21 disturb the distribution of magnitude and phase of dipole 22 near the fences, which will increase the side lobes’voltage in the vertical plane and disturb the neighboring cells; (3) It will take more time and more labor to assemble the fences 21 onto the reflector, and causing disturbance to the system; (4) Instability will be caused to the antenna system work since the amount of fences 21 is huge and the uncertainty in the configuration process.
  • the fences 21 affect the impedance of a single dipole 22 in the array, as shown in Figs. 2b and 2c.
  • Fig. 2b shows a diagram in which the fences have not been applied to affect the impedance.
  • Fig. 2c shows a diagram in which the fences have been applied to affect the impedance. As shown in Fig. 2c, after applying fence 21, the impedance curve will be divergent and is difficult to be adjusted in the application.
  • the present invention provides an antenna dipole unit with an asymmetric dipole.
  • an antenna dipole unit with an asymmetric dipole comprising: a first dipole arm pair, including a first dipole arm and a second dipole arm; a second dipole arm pair, including a third dipole arm and a fourth dipole arm; a feed module, through which the first dipole arm pair and the second dipole arm pair are connected to a RF device; wherein the first dipole arm pair and the second dipole arm pair are orthogonal with each other, and the first dipole arm pair and/or the second dipole arm pair composes an asymmetric structure respectively.
  • an electrical length from the feed module to an end of the first dipole arm is less than an electrical length from the feed module to an end of the second dipole arm, wherein a first metal stick is disposed at the end of the first dipole arm for increasing an effective electrical length of the first dipole arm, wherein the effective electrical length of the first dipole arm is sum of an electrical length corresponding to the first metal stick and an electrical length of the first dipole arm; and/or an electrical length from the feed module to an end of the third dipole arm is less than an electrical length from the feed module to an end of the fourth dipole arm, wherein a second metal stick is disposed at the end of the third dipole arm for increasing an effective electrical length of the third dipole arm, wherein the effective electrical length of the third dipole arm is sum of an electrical length corresponding to the second metal stick and an electrical length of the third dipole arm.
  • the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength; and/or the effective electrical length of the third dipole arm is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength.
  • the electrical length of the first dipole arm is equal to an electrical length of the second dipole arm, wherein an arm length of the first dipole arm is greater than an arm length of the second dipole arm; and/or the electrical length of the third dipole arm is equal to an electrical length of the fourth dipole arm, wherein an arm length of the third dipole arm is greater than an arm length of the fourth dipole arm.
  • a difference between the arm length of the first dipole arm and the arm length of the second dipole arm is less than or equal to one-eighth of the wavelength; and/or a difference between the arm length of the third dipole arm and the arm length of the fourth dipole arm is less than or equal to one-eighth of the wavelength.
  • an electrical length of the first dipole arm is less than an electrical length of the second dipole arm; an electrical length of the third dipole arm is less than an electrical length of the fourth dipole arm; the feed module includes at least two feed slices; the first dipole arm and the second dipole arm use the feed slices to feed through a coupling manner; wherein a first metal corner and a third metal corner is disposed at an end of the first dipole arm and an end of the third dipole arm respectively to increase an effective electrical length of the first dipole arm and the third dipole arm.
  • a sum of an effective electrical length of the first metal corner and the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength; and a sum of an effective electrical length of the second metal corner and the effective electrical length of the third dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength.
  • the antenna dipole is made by metal or implemented by attaching metal to nonmetal.
  • the present invention compensates feed unbalance caused by the feed manner, enables the symmetry of the pattern in horizontal plane of the asymmetric dipole antenna, and enhances the cross polarization discrimination. Further, since the dipole and its feed point/slice are designed as a single unit, additional compensation for the antenna is avoided, and thereby a symmetric radiation direction is provided. By applying the asymmetric dipole antenna of the present invention, the usage of the fences could be reduced, and the cost will decrease.
  • Fig. 1 illustrates a diagram of a symmetric antenna dipole unit in prior art
  • Fig. 2a illustrates a diagram of an array which applies fences and symmetric antenna unit in the prior unit
  • Fig. 2b shows a diagram in which the fences have not been applied to affect the impedance in the prior art
  • Fig. 2c shows a diagram in which the fences have been applied to affect the impedance in the prior art
  • Fig. 3a shows a top view of an asymmetric dipole according to one embodiment of the present invention
  • Fig. 3b shows a whole view of an asymmetric dipole according to one embodiment of the present invention
  • Fig. 3c shows another embodiment of the present invention
  • Fig. 3d shows another embodiment of the present invention
  • Fig. 4a is a simulation diagram for the azimuth patterns of the symmetric dipole unit in prior art
  • Fig. 4b is a simulation diagram for the asymmetric dipole unit according to one embodiment of the present invention.
  • the asymmetry of the azimuth patterns of the antenna dipole unit caused by feed is substantially the inconformity of the electrical length when each dipole arm is transmitting the electromagnetic wave.
  • the electrical length is the ratio of the physical length of the transmission line to the transmission wavelength (in the transmission line) .
  • the physical length of the transmission line is 1m.
  • the electrical length will be 10 and 100. That is, in one meter transmission line, the wave, the wavelength of which is 10cm, changes 10 periods, and the wave, the wavelength of which is 1cm, changes 100 periods.
  • the electrical length is determined by the arm length of the dipole and the distance from the feed point to the dipole arm.
  • Fig. 3a shows a top view of an asymmetric dipole according to one embodiment of the present invention.
  • a dipole 30 is mounted on the PCB, which comprises a first dipole arm pair and a second dipole arm pair. Those two dipole arm pairs are orthogonal in +45°and -45°direction.
  • the first dipole arm pair includes dipole arms 31 and 32, and the second dipole arm pair includes dipole arms 33 and 34.
  • the dipole arms 31 and 32 are symmetric in shape.
  • the dipole arms 33 and 34 are symmetric in shape.
  • Fig. 3b shows a whole view of an asymmetric dipole according to one embodiment of the present invention.
  • cables 35a and 36a are used respectively to feed the dipole 30.
  • the connection point of the cables and the dipole arms is the feed point, that is, feed points 35 and 36.
  • the first and second dipole arms are connected to the RF device through the feed points 35 and 36.
  • the feed point 35 is closer to an end of the dipole arm 31, and the feed point 36 is closer to an end of the dipole arm 33, that is,the feed points 35 and 36 are surrounded by the dipole arms 31 and 33, respectively.
  • the electrical length from the feed point 35 to the end of the dipole arm 31 is k*L1, wherein L1 is the physical length of the dipole arm 31, and k is a relationship coefficient for the physical length and the electrical length.
  • the electrical length k*L1 is less than the electrical length k*L2 from the feed point 35 to the end of the dipole arm 32.
  • the electrical length k*L3 from the feed point 36 to an end of the dipole arm 33 is less than the electrical length k*L4 from the feed point 35 to an end of the dipole arm 34.
  • an effective electrical length of the dipole arm 31 includes: (1) the electrical length from the feed point 35 to the end of the dipole arm 31; (2) the electrical length k*L5 corresponding to the mental stick 37. Therefore, the mental stick 37 extends the effective electrical length of the dipole arm 31.
  • the effective electrical length of the dipole arm length 31 is identical with the electrical length of the dipole arm 32.
  • the effective electrical length of the dipole arm 33 increases because of the mental stick 38, and thus is identical with the electrical length of the dipole arm 34.
  • the effective electrical length of the dipole arms 31 and 32 is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength.
  • the length of the mental stick 37 (or 38) can be adjusted properly according to the application condition and the environment, such that the azimuth patterns of the antenna will be symmetric.
  • the mental stick 37 and/or the mental stick 38 are vertical towards upside or downside at the ends of the dipole arms 31 and 33, such that the symmetry of the azimuth patterns will be higher, and easier to be processed.
  • Fig. 3c shows another embodiment of the present invention.
  • the feed manner of the antenna in Fig. 3c is identical with the feed manner of the antenna in Fig. 3b, and the implementation manner of the dipole is identical. Therefore, its feed manner and the corresponding relationship between the cables and the dipole arms will not be discussed again.
  • a portion of the dipole arms 32 and 34 of the antenna in Fig. 3c is cut to compensate the effect of the feed unbalance.
  • the cut portion can be located at the ends of the dipole arms 32 and 34, for example (as indicated by the dash line) .
  • the effective electrical length of the dipole arms 32 and 34 after the cut has decreased k*L7 and k*L8, respectively. As such, if L1 ⁇ L2-L8, the feed of the antenna will reach balance, and enables the symmetry of the azimuth patterns.
  • the size and the shape of the cut portion can be adjusted properly according to the application condition and the environment, such that the azimuth patterns of the antenna will be symmetric.
  • the dipole arms in Figs. 3a and 3c forms on the PCB.
  • the shape and the size of the dipole arm can be adjusted according to the requirement of the application.
  • the dipole 40 is a mental pressure casting antenna, for example.
  • the dipole 40 includes a first dipole arm pair, a second dipole arm pair and feed slice group 47.
  • the first dipole arm pair includes shape-symmetric dipole arms 41 and 42.
  • the second dipole arm pair includes shape-symmetric dipole arms 43 and 44.
  • the feed slice group 42 composes of two feed slices, and correspondingly includes two feed ends 47a and couple ends 47b. Compared with the dipole arms 42 and 44, the feed ends 47a are closer to the dipole arms 41 and 43. Therefore, the electrical distance of each pair of the dipole arm has an asymmetric problem, which will cause the asymmetry of the horizontal azimuth patterns.
  • the mental corners 45 and 46 with a proper length additionally downwards at the ends of the feed end dipole arms, that is, the dipole arms 41 and 43, for example, the distortion of the azimuth patterns caused by the asymmetric feed can be effectively compensated.
  • the electrical distance between the end of the dipole arm 41 and the feed slice group is less. Therefore, the mental corner 45 can increase the effective electrical length of the dipole arm 41.
  • the effective electrical length of the dipole arm 41 includes the electrical distance between the end of the dipole arm 41 and the feed slice group and the electrical length corresponding to the mental corner 45.
  • the effective electrical length is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength. Therefore, the mental corner 45 compensates the electrical length unbalance between the dipole arms 41 and 42 caused by the feed manner. According to an embodiment, the mental corner at the end of the dipole arm can be pressure casting with the dipole.
  • the mental corners 45 and/or 46 are vertical towards upside or downside at the ends of the dipole arms 41 and 43, such that the symmetry of the azimuth patterns will be higher, and easier to be processed.
  • Fig. 4a is a simulation diagram for the azimuth patterns of the symmetric dipole unit in prior art.
  • Fig. 4b is a simulation diagram for the asymmetric dipole unit according to one embodiment of the present invention.
  • the cross polarization electrical level with the asymmetric antenna dipole unit will decrease about 3dB, and the cross polarization discrimination will be enhanced 3dB. This means that the orthogonality of the signal that antenna can obtain strengthens, the correlation between the two signals decreases, and the polarization effect is enhanced.
  • the shape and size of the compensation portion (for example, mental corner, mental stick, cut portion) can be adjusted according to the requirement of the application to realize the feed balance of the dipole.
  • the present invention is discussed in the context that two dipole arms pairs have feed unbalance.
  • the structure or idea of the present invention can also be applied to compensate or reduce the dipole arm which has feed unbalance.

Landscapes

  • Variable-Direction Aerials And Aerial Arrays (AREA)
  • Details Of Aerials (AREA)

Abstract

The invention provides an antenna dipole unit with an asymmetric dipole, comprising: a first dipole arm pair, including a first dipole arm and a second dipole arm; a second dipole arm pair, including a third dipole arm and a fourth dipole arm, a feed module, through which the first dipole arm pair and the second dipole arm pair are connected to a RF device; wherein the first dipole arm pair and the second dipole arm pair are orthogonal with each other, and the first dipole arm pair and/or the second dipole arm pair composes an asymmetric structure respectively. Through an asymmetric structural dipole antenna, feed unbalance caused by the feed manner is compensated, the symmetry of the pattern in horizontal plane of the asymmetric dipole antenna is enabled, and the cross polarization discrimination is enhanced. Further, since the dipole and its feed point/slice are designed as a single unit, additional compensation for the antenna is avoided, and thereby a symmetric radiation direction is provided. By applying the asymmetric dipole antenna of the present invention, the usage of the fences could be reduced, and the cost will decrease.

Description

ANTENNA DIPOLE UNIT WITH AN ASYMMETRIC DIPOLE Field of the invention
The present disclosure relates to wireless communication field， and particularly to an antenna dipole unit with an asymmetric dipole.
Background of the invention
Nowadays， how to solve the capacity and interference problem in the network high service density， to enhance call completing rate， decrease call drop rate and enhance the call quality has become a key and important issue in the recent work in the communication network construction and maintenance. Applying suitable antenna technology is one of the methods for controlling the coverage effectively， decrease same frequency interference and improve the signal of the cell phone.
Fig. 1 shows a dual polarization base station antenna unit in prior art， which makes up an array and forms a polarization antenna array， which is orthogonal with each other in +45°and -45°direction polarization. This polarization antenna array works at a receiving mode and a transmitting mode simultaneously. The base station antenna consists of dipole group array. Each dipole includes four  dipole arms  11， 12， 13 and 14.Two of the four dipole arms work with a +45°polarization direction， and the other two dipole arms work with a -45°polarization direction. Usually， as the radiation unit of the dipole of the base station antenna， the lengths of those four dipole arms are same， and the shapes thereof are same， too. Currently， in the design of the base station antenna， it is required that azimuth patterns are as symmetric as possible get better cell capacity， to minimize unwanted scattered radiation from one cell to the other and to improve the effect of cell vesture. The other key reason for the design and use of antenna array with symmetric azimuth patterns is that the cross polarization discrimination (XPD) will rise with improved  symmetry.
Fig. 1 shows an example of the symmetric antenna dipole art in prior art. The pattern in horizontal plane of the array composed by these symmetric dipoles will be asymmetric， because of the unbalanced feed of dipole. This will result in low cross polarization discrimination.
Fig. 2a shows an array which applies fences and a symmetric antenna dipole unit in prior art. While the symmetry can be realized effectively by using the fences 21， the antenna system will have following drawbacks after using the fences 21： (1) The fences 21 impact the VSWR of dipole 22 creating some impedance mismatch and worsening the whole antenna array VSWR； (2) The fences 21 disturb the distribution of magnitude and phase of dipole 22 near the fences， which will increase the side lobes’voltage in the vertical plane and disturb the neighboring cells； (3) It will take more time and more labor to assemble the fences 21 onto the reflector， and causing disturbance to the system； (4) Instability will be caused to the antenna system work since the amount of fences 21 is huge and the uncertainty in the configuration process.
Additionally， the fences 21 affect the impedance of a single dipole 22 in the array， as shown in Figs. 2b and 2c. Fig. 2b shows a diagram in which the fences have not been applied to affect the impedance. Fig. 2c shows a diagram in which the fences have been applied to affect the impedance. As shown in Fig. 2c， after applying fence 21， the impedance curve will be divergent and is difficult to be adjusted in the application.
Thus， an economic antenna system with high stability is needed.
Summary of the invention
In view of this， the present invention provides an antenna dipole unit with an asymmetric dipole.
According to a first aspect of the invention， there is proposed an antenna dipole unit with an asymmetric dipole， comprising： a first dipole arm pair， including a first dipole arm and a second dipole arm； a second  dipole arm pair， including a third dipole arm and a fourth dipole arm； a feed module， through which the first dipole arm pair and the second dipole arm pair are connected to a RF device； wherein the first dipole arm pair and the second dipole arm pair are orthogonal with each other， and the first dipole arm pair and/or the second dipole arm pair composes an asymmetric structure respectively.
According to an embodiment of the present invention， an electrical length from the feed module to an end of the first dipole arm is less than an electrical length from the feed module to an end of the second dipole arm， wherein a first metal stick is disposed at the end of the first dipole arm for increasing an effective electrical length of the first dipole arm， wherein the effective electrical length of the first dipole arm is sum of an electrical length corresponding to the first metal stick and an electrical length of the first dipole arm； and/or an electrical length from the feed module to an end of the third dipole arm is less than an electrical length from the feed module to an end of the fourth dipole arm， wherein a second metal stick is disposed at the end of the third dipole arm for increasing an effective electrical length of the third dipole arm， wherein the effective electrical length of the third dipole arm is sum of an electrical length corresponding to the second metal stick and an electrical length of the third dipole arm.
According to an embodiment of the present invention， the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength； and/or the effective electrical length of the third dipole arm is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength.
According to an embodiment of the present invention， the electrical length of the first dipole arm is equal to an electrical length of the second dipole arm， wherein an arm length of the first dipole arm is greater than an arm length of the second dipole arm； and/or the electrical length of the  third dipole arm is equal to an electrical length of the fourth dipole arm， wherein an arm length of the third dipole arm is greater than an arm length of the fourth dipole arm.
According to an embodiment of the present invention， a difference between the arm length of the first dipole arm and the arm length of the second dipole arm is less than or equal to one-eighth of the wavelength； and/or a difference between the arm length of the third dipole arm and the arm length of the fourth dipole arm is less than or equal to one-eighth of the wavelength.
According to an embodiment of the present invention， an electrical length of the first dipole arm is less than an electrical length of the second dipole arm； an electrical length of the third dipole arm is less than an electrical length of the fourth dipole arm； the feed module includes at least two feed slices； the first dipole arm and the second dipole arm use the feed slices to feed through a coupling manner； wherein a first metal corner and a third metal corner is disposed at an end of the first dipole arm and an end of the third dipole arm respectively to increase an effective electrical length of the first dipole arm and the third dipole arm.
According to an embodiment of the present invention， a sum of an effective electrical length of the first metal corner and the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength； and a sum of an effective electrical length of the second metal corner and the effective electrical length of the third dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength.
According to an embodiment of the present invention， the antenna dipole is made by metal or implemented by attaching metal to nonmetal.
By designing an asymmetric structural dipole antenna， the present invention compensates feed unbalance caused by the feed manner， enables the symmetry of the pattern in horizontal plane of the asymmetric dipole  antenna， and enhances the cross polarization discrimination. Further， since the dipole and its feed point/slice are designed as a single unit， additional compensation for the antenna is avoided， and thereby a symmetric radiation direction is provided. By applying the asymmetric dipole antenna of the present invention， the usage of the fences could be reduced， and the cost will decrease.
Brief description of drawings
Other features， objects and advantages of the invention will become more apparent upon review of the following detailed description of non-limiting embodiments taken with reference to the drawings in which：
Fig. 1 illustrates a diagram of a symmetric antenna dipole unit in prior art；
Fig. 2a illustrates a diagram of an array which applies fences and symmetric antenna unit in the prior unit；
Fig. 2b shows a diagram in which the fences have not been applied to affect the impedance in the prior art；
Fig. 2c shows a diagram in which the fences have been applied to affect the impedance in the prior art；
Fig. 3a shows a top view of an asymmetric dipole according to one embodiment of the present invention；
Fig. 3b shows a whole view of an asymmetric dipole according to one embodiment of the present invention；
Fig. 3c shows another embodiment of the present invention；
Fig. 3d shows another embodiment of the present invention；
Fig. 4a is a simulation diagram for the azimuth patterns of the symmetric dipole unit in prior art；
Fig. 4b is a simulation diagram for the asymmetric dipole unit according to one embodiment of the present invention.
Detailed description of embodiments
The preferable embodiments of the present invention will be discussed in detail with reference to the figures. While the figures show the preferable embodiments of the present invention， it should be appreciated that the present disclosure could be implemented by various embodiments， but not limited to the embodiments discussed herein. On the contrary， those embodiments are provided for the clearness and completeness of the disclosure， and for conveying the coverage of the disclosure to those skilled in the art completely.
In prior art， the asymmetry of the azimuth patterns of the antenna dipole unit caused by feed is substantially the inconformity of the electrical length when each dipole arm is transmitting the electromagnetic wave. The electrical length is the ratio of the physical length of the transmission line to the transmission wavelength (in the transmission line) . For example， the physical length of the transmission line is 1m. For two electromagnetic waves， the wavelengths of which are 10cm and 1cm respectively， the electrical length will be 10 and 100. That is， in one meter transmission line， the wave， the wavelength of which is 10cm， changes 10 periods， and the wave， the wavelength of which is 1cm， changes 100 periods. Apparently， more frequently the electromagnetic wave changes in a same physical length， much greater the electrical length is. In other words， when transmitting the same electromagnetic wave， the electrical length is determined by the arm length of the dipole and the distance from the feed point to the dipole arm.
Fig. 3a shows a top view of an asymmetric dipole according to one embodiment of the present invention. A dipole 30 is mounted on the PCB， which comprises a first dipole arm pair and a second dipole arm pair. Those two dipole arm pairs are orthogonal in +45°and -45°direction. The first dipole arm pair includes  dipole arms  31 and 32， and the second dipole arm pair includes  dipole arms  33 and 34. The  dipole arms  31 and 32 are symmetric in shape. Identically， the  dipole arms  33 and 34 are symmetric in shape.
Fig. 3b shows a whole view of an asymmetric dipole according to one embodiment of the present invention. In the embodiment，  cables  35a and 36a are used respectively to feed the dipole 30. The connection point of the cables and the dipole arms is the feed point， that is， feed points 35 and 36.The first and second dipole arms are connected to the RF device through the feed points 35 and 36.
In this embodiment， the feed point 35 is closer to an end of the dipole arm 31， and the feed point 36 is closer to an end of the dipole arm 33， that is，the feed points 35 and 36 are surrounded by the  dipole arms  31 and 33， respectively. Thus， the electrical length from the feed point 35 to the end of the dipole arm 31 is k*L1， wherein L1 is the physical length of the dipole arm 31， and k is a relationship coefficient for the physical length and the electrical length. Apparently， the electrical length k*L1 is less than the electrical length k*L2 from the feed point 35 to the end of the dipole arm 32. Identically， the electrical length k*L3 from the feed point 36 to an end of the dipole arm 33 is less than the electrical length k*L4 from the feed point 35 to an end of the dipole arm 34. Thus， there is an electrical length asymmetric situation for the first and second dipole arm， respectively， which will cause the asymmetry of the horizontal azimuth patterns of the antenna.
In order to eliminate the asymmetry of the azimuth patterns caused by the feed manner， in this embodiment，  mental sticks  37 and 38 with length L5 and L6 are disposed additionally at the ends of the  dipole arms  31 and 33，respectively. In the example for the dipole arm 31 and the mental stick 37，now an effective electrical length of the dipole arm 31 includes： (1) the electrical length from the feed point 35 to the end of the dipole arm 31； (2) the electrical length k*L5 corresponding to the mental stick 37. Therefore， the mental stick 37 extends the effective electrical length of the dipole arm 31.
Apparently， when Li+L5≈L2， the effective electrical length of the dipole arm length 31 is identical with the electrical length of the dipole  arm 32. For the same reason， the effective electrical length of the dipole arm 33 increases because of the mental stick 38， and thus is identical with the electrical length of the dipole arm 34. By adjusting the effective electrical length of the two  dipole arms  31 and 33， the azimuth patterns of the antenna 31 will be symmetric. The effective electrical length of the  dipole arms  31 and 32 is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength.
It shall be appreciated for those skilled in the art in the practical application the length of the mental stick 37 (or 38) can be adjusted properly according to the application condition and the environment， such that the azimuth patterns of the antenna will be symmetric. Preferably， the mental stick 37 and/or the mental stick 38 are vertical towards upside or downside at the ends of the  dipole arms  31 and 33， such that the symmetry of the azimuth patterns will be higher， and easier to be processed.
Fig. 3c shows another embodiment of the present invention. The feed manner of the antenna in Fig. 3c is identical with the feed manner of the antenna in Fig. 3b， and the implementation manner of the dipole is identical. Therefore， its feed manner and the corresponding relationship between the cables and the dipole arms will not be discussed again. In order to balance the effective electrical length of the  dipole arms  31 and 32，a portion of the  dipole arms  32 and 34 of the antenna in Fig. 3c is cut to compensate the effect of the feed unbalance. The cut portion can be located at the ends of the  dipole arms  32 and 34， for example (as indicated by the dash line) . The effective electrical length of the  dipole arms  32 and 34 after the cut has decreased k*L7 and k*L8， respectively. As such， if L1≈L2-L8， the feed of the antenna will reach balance， and enables the symmetry of the azimuth patterns.
It shall be appreciated for those skilled in the art in the practical application the size and the shape of the cut portion can be adjusted properly according to the application condition and the environment， such that the azimuth patterns of the antenna will be symmetric. Further， the  dipole arms in Figs. 3a and 3c forms on the PCB. The shape and the size of the dipole arm can be adjusted according to the requirement of the application.
Fig. 3d shows another embodiment of the present invention. The dipole 40 is a mental pressure casting antenna， for example. The dipole 40 includes a first dipole arm pair， a second dipole arm pair and feed slice group 47. Correspondingly， the first dipole arm pair includes shape- symmetric dipole arms  41 and 42. The second dipole arm pair includes shape- symmetric dipole arms  43 and 44. The feed slice group 42 composes of two feed slices， and correspondingly includes two feed ends 47a and couple ends 47b. Compared with the  dipole arms  42 and 44， the feed ends 47a are closer to the  dipole arms  41 and 43. Therefore， the electrical distance of each pair of the dipole arm has an asymmetric problem， which will cause the asymmetry of the horizontal azimuth patterns. Therefore， by disposing the mental corners 45 and 46 with a proper length additionally downwards at the ends of the feed end dipole arms， that is， the  dipole arms  41 and 43， for example， the distortion of the azimuth patterns caused by the asymmetric feed can be effectively compensated. In the example for the dipole arm 41 and mental corner 45， compared with the dipole arm 42， the electrical distance between the end of the dipole arm 41 and the feed slice group is less. Therefore， the mental corner 45 can increase the effective electrical length of the dipole arm 41. Now， the effective electrical length of the dipole arm 41 includes the electrical distance between the end of the dipole arm 41 and the feed slice group and the electrical length corresponding to the mental corner 45. The effective electrical length is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength. Therefore， the mental corner 45 compensates the electrical length unbalance between the  dipole arms  41 and 42 caused by the feed manner. According to an embodiment， the mental corner at the end of the dipole arm can be pressure casting with the dipole.
Preferably， the mental corners 45 and/or 46 are vertical towards upside or downside at the ends of the  dipole arms  41 and 43， such that the symmetry of the azimuth patterns will be higher， and easier to be processed.
Fig. 4a is a simulation diagram for the azimuth patterns of the symmetric dipole unit in prior art. Fig. 4b is a simulation diagram for the asymmetric dipole unit according to one embodiment of the present invention.
From the two simulation diagrams， after applying the asymmetric antenna dipole unit， since the asymmetric antenna dipole can adjust the electrical length of the arm length， the cross polarization electrical level with the asymmetric antenna dipole unit will decrease about 3dB， and the cross polarization discrimination will be enhanced 3dB. This means that the orthogonality of the signal that antenna can obtain strengthens， the correlation between the two signals decreases， and the polarization effect is enhanced.
In the practical application， the shape and size of the compensation portion (for example， mental corner， mental stick， cut portion) can be adjusted according to the requirement of the application to realize the feed balance of the dipole. In the above， the present invention is discussed in the context that two dipole arms pairs have feed unbalance. In fact， in the context that only one dipole arm pair has feed unbalance， the structure or idea of the present invention can also be applied to compensate or reduce the dipole arm which has feed unbalance.
The above description of the present disclosure is used to realize that those skilled in the art can implement or use the present invention. Various modifications of the present disclosure are appreciated for those skilled in the art. Further， the general principal defined in the description can be applied into other variations without departing from the spirit and the protection scope of the invention. Therefore， the present invention is not limited to the embodiments and design described herein， rather is  conform to the largest scope of the principle and novelty of the present disclosure.

Claims (8)

  1. An antenna dipole unit with an asymmetric dipole， comprising：
    a first dipole arm pair， including a first dipole arm and a second dipole arm；
    a second dipole arm pair， including a third dipole arm and a fourth dipole arm；
    a feed module， through which the first dipole arm pair and the second dipole arm pair are connected to a RF device；
    wherein the first dipole arm pair and the second dipole arm pair are orthogonal with each other， and the first dipole arm pair and/or the second dipole arm pair composes an asymmetric structure respectively.
  2. An antenna dipole according to claim 1， wherein an electrical length from the feed module to an end of the first dipole arm is less than an electrical length from the feed module to an end of the second dipole arm， wherein a first metal stick is disposed at the end of the first dipole arm for increasing an effective electrical length of the first dipole arm， wherein the effective electrical length of the first dipole arm is sum of an electrical length corresponding to the first metal stick and an electrical length of the first dipole arm； and/or
    an electrical length from the feed module to an end of the third dipole arm is less than an electrical length from the feed module to an end of the fourth dipole arm， wherein a second metal stick is disposed at the end of the third dipole arm for increasing an effective electrical length of the third dipole arm， wherein the effective electrical length of the third dipole arm is sum of an electrical length corresponding to the second metal stick and an electrical length of the third dipole arm.
  3. An antenna dipole according to claim 2， wherein
    the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength； and/or
    the effective electrical length of the third dipole arm is equal or greater than one-eighth of the wavelength and less than or equal to one half of the wavelength.
  4. An antenna dipole according to claim 1， wherein the electrical length of the first dipole arm is equal to an electrical length of the second dipole arm， wherein an arm length of the first dipole arm is greater than an arm length of the second dipole arm； and/or
    the electrical length of the third dipole arm is equal to an electrical length of the fourth dipole arm， wherein an arm length of the third dipole arm is greater than an arm length of the fourth dipole arm.
  5. An antenna dipole according to claim 4， wherein a difference between the arm length of the first dipole arm and the arm length of the second dipole arm is less than or equal to one-eighth of the wavelength； and/or
    a difference between the arm length of the third dipole arm and the arm length of the fourth dipole arm is less than or equal to one-eighth of the wavelength.
  6. An antenna dipole according to claim 1， wherein an electrical length of the first dipole arm is less than an electrical length of the second dipole arm； an electrical length of the third dipole arm is less than an electrical length of the fourth dipole arm； the feed module includes at least two feed slices； the first dipole arm and the second dipole arm use the feed slices to feed through a coupling manner； wherein a first metal corner and a third metal corner is disposed at an end of the first dipole arm and an end of the third dipole arm respectively to increase an effective electrical length of the first dipole arm and the third dipole arm.
  7. An antenna dipole according to claim 6， wherein a sum of an effective electrical length of the first metal corner and the effective electrical length of the first dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength； and a sum of an effective electrical length of the second metal corner and the effective  electrical length of the third dipole arm is equal or greater than one-eighth of a wavelength and less than or equal to one half of the wavelength.
  8. An antenna dipole according to anyone of claims 1 to 7， wherein the antenna dipole is made by metal or implemented by attaching metal to nonmetal.
PCT/CN2014/090102 2013-11-01 2014-10-31 Antenna dipole unit with an asymmetric dipole WO2015062545A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201310534832.7 2013-11-01
CN201310534832.7A CN103633422A (en) 2013-11-01 2013-11-01 Antenna oscillator unit using asymmetric oscillator

Publications (1)

Publication Number Publication Date
WO2015062545A1 true WO2015062545A1 (en) 2015-05-07

Family

ID=50214200

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2014/090102 WO2015062545A1 (en) 2013-11-01 2014-10-31 Antenna dipole unit with an asymmetric dipole

Country Status (2)

Country Link
CN (1) CN103633422A (en)
WO (1) WO2015062545A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9966656B1 (en) 2016-11-08 2018-05-08 Aeternum LLC Broadband rectenna
TWI643399B (en) * 2017-08-01 2018-12-01 譁裕實業股份有限公司 Dipole antenna vibrator
US20190280388A1 (en) * 2016-10-21 2019-09-12 Nokia Shanghai Bell Co., Ltd. Dipole
EP3614491A1 (en) * 2018-08-24 2020-02-26 CommScope Technologies LLC Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
CN111952723A (en) * 2020-09-08 2020-11-17 山东华箭科工创新科技有限公司 5G full-band printed log periodic antenna loaded with metal oscillator
US11133576B2 (en) 2017-08-28 2021-09-28 Aeternum, LLC Rectenna

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103633422A (en) * 2013-11-01 2014-03-12 安弗施无线射频系统（上海）有限公司 Antenna oscillator unit using asymmetric oscillator
CN103972643B (en) * 2014-05-14 2017-06-06 京信通信系统（中国）有限公司 Array antenna and its local asymmetric radiating element
CN108923116B (en) * 2018-06-29 2021-03-19 京信通信技术(广州)有限公司 High-frequency radiation unit and multi-frequency array antenna
CN112864591B (en) * 2020-12-30 2022-08-19 京信通信技术(广州)有限公司 Base station, antenna and radiating element thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101673874A (en) * 2009-10-13 2010-03-17 厦门大学 Unsymmetrical double dipole antenna used for vehicle-mounted digital television
US20110068992A1 (en) * 2009-08-03 2011-03-24 Venti Group, LLC Cross-dipole antenna configurations
CN102426656A (en) * 2011-08-16 2012-04-25 中兴通讯股份有限公司 Multi-antenna mobile phone data card capable of reducing specific absorption rate, and method of the same
CN203192944U (en) * 2012-03-19 2013-09-11 盖尔创尼克斯有限公司 Dual-band dual-polarized antenna
CN103633422A (en) * 2013-11-01 2014-03-12 安弗施无线射频系统（上海）有限公司 Antenna oscillator unit using asymmetric oscillator
CN203631726U (en) * 2013-11-01 2014-06-04 安弗施无线射频系统（上海）有限公司 Antenna oscillator unit with asymmetric oscillators

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101599579B (en) * 2008-06-05 2016-08-10 京信通信系统（中国）有限公司 High cross polarization ratio antenna and dual-polarization radiating unit thereof
CN103036009B (en) * 2011-09-30 2014-12-10 京信通信系统（中国）有限公司 Asymmetric dual polarized broadband radiation unit and array antenna

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110068992A1 (en) * 2009-08-03 2011-03-24 Venti Group, LLC Cross-dipole antenna configurations
CN101673874A (en) * 2009-10-13 2010-03-17 厦门大学 Unsymmetrical double dipole antenna used for vehicle-mounted digital television
CN102426656A (en) * 2011-08-16 2012-04-25 中兴通讯股份有限公司 Multi-antenna mobile phone data card capable of reducing specific absorption rate, and method of the same
CN203192944U (en) * 2012-03-19 2013-09-11 盖尔创尼克斯有限公司 Dual-band dual-polarized antenna
CN103633422A (en) * 2013-11-01 2014-03-12 安弗施无线射频系统（上海）有限公司 Antenna oscillator unit using asymmetric oscillator
CN203631726U (en) * 2013-11-01 2014-06-04 安弗施无线射频系统（上海）有限公司 Antenna oscillator unit with asymmetric oscillators

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20190280388A1 (en) * 2016-10-21 2019-09-12 Nokia Shanghai Bell Co., Ltd. Dipole
US10957983B2 (en) * 2016-10-21 2021-03-23 Nokia Shanghai Bell Co., Ltd. Dipole
US9966656B1 (en) 2016-11-08 2018-05-08 Aeternum LLC Broadband rectenna
US10090595B2 (en) 2016-11-08 2018-10-02 Aeternum LLC Broadband rectenna
TWI643399B (en) * 2017-08-01 2018-12-01 譁裕實業股份有限公司 Dipole antenna vibrator
US11133576B2 (en) 2017-08-28 2021-09-28 Aeternum, LLC Rectenna
EP3614491A1 (en) * 2018-08-24 2020-02-26 CommScope Technologies LLC Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
US11018437B2 (en) 2018-08-24 2021-05-25 Commscope Technologies Llc Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
EP3955383A1 (en) * 2018-08-24 2022-02-16 CommScope Technologies LLC Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
US11563278B2 (en) 2018-08-24 2023-01-24 Commscope Technologies Llc Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
US11855352B2 (en) 2018-08-24 2023-12-26 Commscope Technologies Llc Multi-band base station antennas having broadband decoupling radiating elements and related radiating elements
CN111952723A (en) * 2020-09-08 2020-11-17 山东华箭科工创新科技有限公司 5G full-band printed log periodic antenna loaded with metal oscillator

Also Published As

Publication number Publication date
CN103633422A (en) 2014-03-12

Similar Documents

Publication Publication Date Title
WO2015062545A1 (en) Antenna dipole unit with an asymmetric dipole
US8638270B2 (en) Cross-dipole antenna configurations
CN102013560B (en) Broadband high-performance dual-polarization radiation unit and antenna
WO2018001007A1 (en) Dense array antenna for use in 5g system
US8289218B2 (en) Cross-dipole antenna combination
US9748655B2 (en) Polarization antenna
KR100695330B1 (en) Isolation Antenna for Repeater
US10186778B2 (en) Wideband dual-polarized patch antenna array and methods useful in conjunction therewith
US20090278759A1 (en) Dual-Band Dual-Polarized Base Station Antenna for Mobile Communication
WO2016065859A1 (en) Intelligent antenna device
US20190288406A1 (en) Antenna feed structure and base station antenna
EP3465823B1 (en) C-fed antenna formed on multi-layer printed circuit board edge
US20160036130A1 (en) Planar Dual Polarization Antenna and Complex Antenna
US20140071016A1 (en) Dual-band and dual-polarization antenna
US8427385B2 (en) Cross-dipole antenna
CN207217751U (en) A kind of dual polarized antenna and aerial array
US9583819B2 (en) Antenna device including a phase shifter and a feeding portion configured as a triplate line with a center conductor
CN203631726U (en) Antenna oscillator unit with asymmetric oscillators
US10749253B2 (en) Omnidirectional ceiling antenna
KR101605359B1 (en) Broad-band Array Antenna for Mobile Communication Base Station
CN102760976B (en) Radiating unit of dual-polarization antenna and dual-polarization antenna
CN105337041A (en) Full-band television transmitting antenna based on rhombic oscillators
KR20110088177A (en) The dipole device of hybrid type and dual polarization array antenna using that device
CN203288741U (en) Miniature high-gain symmetrical-oscillator omnidirectional antenna
CN105337024A (en) Vertically polarized ground television transmitting antenna based on disk oscillator

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14857522

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 14857522

Country of ref document: EP

Kind code of ref document: A1