The present disclosure relates to an antenna technology suitable for a mobile communication (personal communication service (PCS), cellular, international mobile telecommunication-2000 (IMT-2000) or the like) base station or relay, and more particularly, to a multi-band antenna.
Along with the popularity of mobile communications and wireless broadband data communication, efforts are now made to render various frequency bands to be available due to the lack of frequency bands. Multiple input and multiple output (MIMO) based on multiple antennas is a requisite technology to increase data rate, finding its applications in mobile communication network systems such as long term evolution (LTE) and mobile worldwide interoperability for microwave access (Mobile WiMAX).
The first antenna array 9 may be arranged at the center of the reflective plate, the (2-1)th and (3-1)th antenna arrays 11 and 31 may be arranged on the right side of the first antenna array 9, and the (2-2)th and (3-2)th antenna arrays 12 and 32 may be arranged on the left side of the first antenna array 9. It may be understood that the (2-1)th and (2-2)th antenna arrays 11 and 12, and the (3-1)th and (3-2)th antenna arrays 31 and 32 are installed in a double structure to implement a MIMO antenna of the second band and a MIMO antenna of the third band, respectively in the above-described structure.
The first antenna array 9 is configured generally to include a plurality of radiation modules for the first band arranged vertically in a row. Similarly, each of the (2-1)th and (2-2)th antenna arrays 11 and 12 is configured generally to include a plurality of radiation modules for the second band arranged vertically in a row, and each of the (3-1)th and (3-2)th antenna arrays 31 and 32 is configured generally to include a plurality of radiation modules for the third band arranged vertically in a row. Each of the radiation modules for the first, second, and third bands is configured generally to include four 4-directional radiation elements arranged at +45 degrees and −45 degrees on the whole with respect to a vertical (or horizontal) direction, so that two mutually orthogonal linear polarizations (that is X polarizations) are generated.
Meanwhile, as radiation elements and radiation modules with broadband characteristics have recently been demanded, radiation elements covering a band with a fractional band width of about 45% are offered. Such a radiation element may have an operation characteristic of, for example, a 1710-MHz to 2690-MHz band. If a multi-band antenna is implemented with such broadband radiation elements, the radiation modules for the second and third bands may be configured with broadband radiation elements all having substantially identical structures.
To provide an electrical vertical tilt to total radiation beams emitted from the first antenna array 9 of the first band, the multi-band antenna illustrated in
To provide an electrical vertical tilt to radiation beams emitted from the (2-1)th antenna array 11, the multi-band antenna further includes a (2-1)th phase shifter 41 for receiving an input signal of the second band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-1)th antenna array 11, so that each radiation module or each group of radiation modules may have a predetermined phase difference. The radiation modules of the (2-1)th antenna array 11 may be grouped, for example, by pair, and each group of radiation modules may be connected to the (2-1)th phase shifter 41 through a (2-1)th power divider 13 for the second band. In this case, it may be noted that a phase difference is generated on a radiation module group basis.
Likewise, the multi-band antenna further includes a (2-2)th phase shifter 42 for receiving an input signal of the second band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-2)th antenna array 12, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them. Each of a plurality of groups of radiation modules in the (2-2)th antenna array 12 may be connected to the (2-2)th phase shifter 42 through a (2-2)th power divider 14 for the second band.
The multi-band antenna also includes a (3-1)th phase shifter 51 for receiving an input signal of the third band, dividing the input signal, and providing the divided signals to the radiation modules of the (3-1)th antenna array 31, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them. Each of a plurality of groups of radiation modules in the (3-1)th antenna array 31 may be connected to the (3-1)th phase shifter 51 through a (3-1)th power divider 33 for the third band.
The multi-band antenna further includes a (3-2)th phase shifter 52 for receiving an input signal of the third band, dividing the input signal, and providing the divided signals to the radiation modules of the (3-2)th antenna array 32, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them. Each of a plurality of groups of radiation modules in the (3-2)th antenna array 32 may be connected to the (3-2)th phase shifter 52 through a (3-2)th power divider 34 for the third band.
The (2-1)th and (2-2)th power dividers 13 and 14 for the second band, and the (3-1)th and (3-2)th power dividers 33 and 34 for the third band may be designed so as to be used substantially commonly for the second and third bands. In this case, all of the (2-1)th and (2-2)th power dividers 13 and 14, and the (3-1)th and (3-2)th power dividers 33 and 34 may be configured in the substantially same structure. While the term, power divider has been used above, it will be understood that if the directions of input and output signals are reserved, such a power divider may have a configuration for serving as a power combiner.
The multi-band antenna may be configured as illustrated in
The multi-band antenna illustrated in
In the multi-band antenna illustrated in
Although the multi-band antenna illustrated in
As illustrated in
Accordingly, an object of the present disclosure is to provide a multi-band antenna which has an optimized structure and decreases an antenna size, for facilitating antenna design and offering more stable characteristics.
In an aspect of the present invention, a multi-band antenna includes a first antenna array of a first band, including radiation modules for the first band, a (2-1)th antenna array of second and third common bands, including radiation modules for the second and third common bands, a (2-1)th phase shifter for receiving an input signal of the second band, dividing the input signal, and providing divided signals having a phase difference to predetermined radiation modules or a plurality of radiation module groups on a radiation module basis or a radiation module group basis among the radiation modules of the (2-1)th antenna array, a (3-1)th phase shifter for receiving an input signal of the third band, dividing the input signal, and providing divided signals having a phase difference to predetermined radiation modules or a plurality of radiation module groups on a radiation module basis or a radiation module group basis among the radiation modules of the (2-1)th antenna array, and a plurality of (2-1)th frequency combiners each for combining a predetermined one of signals output from the (2-1)th phase shifter with one of signals output from the (3-1)th phase shifter corresponding to the (2-1)th frequency combiner, and providing the combined signal to each of predetermined radiation modules or a predetermined one of a plurality of radiation module groups among the radiation modules of the (2-1)th antenna array.
The radiation modules of the (2-1)th antenna array are divided into a group used for the second or third band, a group for the third band, and a group common for the second and third bands, the group for the second or third band is connected to one of the (2-1)th phase shifter and the (3-1)th phase shifter, corresponding to the group for the second or third band, and the group common for the second and third band is connected to the (2-1)th phase shifter and the (3-1)th phase shifter, through the (2-1)th frequency combiners.
Preferred embodiments of the present disclosure will be described below in detail with reference to the attached drawings. Specific details such as components are given to help comprehensive understanding of the present disclosure, and those skilled in the art will understand that various modifications or variations can be made to the specific details without departing from the scope and spirit of the present disclosure.
The first antenna array 9 may be arranged at the center of the reflective plate, and the (2-1)th and (2-2)th antenna arrays 21 and 22 may be arranged on the left and right sides of the first antenna array 9, respectively. It may be understood that the (2-1)th and (2-2)th antenna arrays 21 and 22 are installed in a double structure to implement a MIMO antenna of the second and third bands in the above-described structure.
The first antenna array 9 is configured generally to include a plurality of radiation modules for the first band arranged vertically in a row. Similarly, each of the (2-1)th and (2-2)th antenna arrays 21 and 22 is configured generally to include a plurality of radiation modules for the second and third common bands arranged vertically in a row. That is, the radiation modules for the second and third common bands may be configured with broadband radiation elements covering both of the second and third bands.
To provide an electrical vertical tilt to total radiation beams emitted from the first antenna array 9 of the first band, the multi-band antenna includes the first phase shifter 10 for receiving an input signal of the first band, dividing the input signal, and providing the divided signals to the radiation modules of the first antenna array 9 in such a manner that the divided signals provided to the radiation modules arranged vertically in a row may have a predetermined phase difference between them.
To provide an electrical vertical tilt to radiation beams emitted from the (2-1)th antenna array 21, the multi-band antenna further includes the (2-1)th phase shifter 41 for receiving an input signal of the second band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-1)th antenna array 21, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them. The radiation modules of the (2-1)th antenna array 21 may be grouped, for example, by pair, and each group of radiation modules may be connected to the (2-1)th phase shifter 41 through one of a plurality of (2-1)'th power dividers 25, provided on a group basis and one of a plurality of (2-1)th frequency combiners 63, provided on a group basis. In this case, it may be noted that a phase difference is generated on a group basis.
The (2-1)th power dividers 25 may be configured as general 2-way power dividers. Besides, the (2-1)th power dividers 25 may be designed to be suitable for the characteristics of the second and third common bands.
Meanwhile, the multi-band antenna further includes the (3-1)th phase shifter 51 for receiving an input signal of the third band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-1)th antenna array 21, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them.
One output terminal (combined terminal) of each of the plurality of (2-1)th frequency combiners 63 is connected to one of the plurality of (2-1)th power dividers 25, corresponding to the (2-1)th frequency combiner 63. One of two input terminals of the (2-1)th frequency combiner 63 is connected to the (2-1)th phase shifter 41 and thus to a corresponding one of divided outputs of the (2-1)th phase shifter 41, whereas the other input terminal of the (2-1)th frequency combiner 63 is connected to a corresponding one of divided outputs of the (3-1)th phase shifter 51. Each of the (2-1)th frequency combiners 63 combines a signal output from the (2-1)th phase shifter 41 with a signal output from the (3-1)th phase shifter 51, and provides the combined signal to a (2-1)th power divider 25 corresponding to the (2-1)th frequency combiner 63.
Each (2-1)th frequency combiner 63 may be a diplexer or duplexer having a filter for filtering the second band and a filter for filtering the third band in combination. While the term, frequency combiner has been used above, it will be understood that if the directions of input and output signals are reserved, this frequency combiner may have a configuration for serving as a frequency divider.
Likewise, the multi-band antenna further includes the (2-2)th phase shifter 42 for receiving an input signal of the second band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-2)th antenna array 22, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them. Each group of radiation modules in the (2-2)th antenna array 22 may be connected to the (2-2)th phase shifter 42 through a corresponding one of a plurality of (2-2)th power dividers 27 and a corresponding one of a plurality of (2-2)th frequency combiners 64.
The multi-band antenna further includes the (3-2)th phase shifter 52 for receiving an input signal of the third band, dividing the input signal, and providing the divided signals to the radiation modules of the (2-2)th antenna array 22, so that the radiation modules or groups of radiation modules may have a predetermined phase difference between them.
In this case, each of the plurality of (2-2)th frequency combiners 64 combines a corresponding one of signals output from the (2-2)th phase shifter 42 with a corresponding a corresponding one of signals output from the (3-2)th phase shifter 52, and provides the combined signal to the (2-2)th power divider 27.
The structure of the multi-band antenna according to the embodiment of the present disclosure, illustrated in
Similarly to the embodiment illustrated in
In the structure according to the second embodiment of the present invention, the radiation modules for the second and third common bands, 21-1, 21-2, . . . , 21-14, and 22-1, 22-2 . . . , 22-14 of the (2-1)th and (2-2)th antenna arrays 21 and 22 may be divided into three groups: a group for the second band, a group for the third band, and a group common for the second and third bands.
Among the radiation modules 21-1, 21-2, . . . , 21-14, of the (2-1)th antenna array 21, in a sequential order, for example, the first to fourth radiation modules 21-1, 21-2, 21-3, and 21-4 are used for the third band, the 5th to 10th radiation modules 21-5, 21-6, 21-7, 21-8, 21-9, and 21-10 are used commonly for the second and third bands, and the 11th to 14th radiation modules 21-11, 21-12, 21-13, and 21-14 are used for the second band,.
That is, in the (2-1)th antenna array 21, the first and second radiation modules 21-1 and 21-2 are connected to a corresponding one of outputs of the (3-1)th phase shifter 51 through a (2-1-1)th power divider 231, and the third and fourth radiation modules 21-3 and 21-4 are connected to a corresponding one of the outputs of the (3-1)th phase shifter 51 through a (2-1-2)th power divider 232. Also, in the (2-1)th antenna array 21, the 11th and 12th radiation modules 21-11 and 21-12 are connected to a corresponding one of outputs of the (2-1)th phase shifter 41 through a (2-1-3)th power divider 233, and the 13th and 14th radiation modules 21-13 and 21-14 are connected to a corresponding one of the outputs of the (2-1)th phase shifter 41 through a (2-1-4)th power divider 234.
In the (2-1)th antenna array 21, the 5th and 6th radiation modules 21-5 and 21-6 are connected to corresponding ones of the outputs of the (3-1)th phase shifter 51 and the (2-1)th phase shifter 41 through a (2-1-5)th power divider 251 and a (2-1-1)th frequency combiner 631, the 7th and 8th radiation modules 21-7 and 21-8 are connected to corresponding ones of the outputs of the (3-1)th phase shifter 51 and the (2-1)th phase shifter 41 through a (2-1-6)th power divider 252 and a (2-1-2)th frequency combiner 632, and the 9th and 10th radiation modules 21-9 and 21-10 are connected to corresponding ones of the outputs of the (3-1)th phase shifter 51 and the (2-1)th phase shifter 41 through a (2-1-7)th power divider 253 and a (2-1-3)th frequency combiner 633.
The (2-1-1)th to (2-1-4)th power dividers 231 to 234 may be designed suitably for characteristics of the second and third common bands, and the (2-1-5)th, (2-1-6)th, and (2-1-7)th power dividers 251, 252, and 253 may be configured as general 2-way power dividers.
In the above structure, each of the (2-1-1)th, (2-1-2)th, and (2-1-3)th frequency combiners 631, 632, and 633 is configured to combine a corresponding one of signals output from the (2-1)th phase shifter 41 with a corresponding one of signals output from the (3-1)th phase shifter 51 and provide the combined signal to a corresponding one of the (2-1-5)th, (2-1-6)th , and (2-1-7)th power dividers 251, 252, and 253.
Meanwhile, the (2-2)th antenna array 22 and its feeding network structure may be designed to be symmetrically same as the (2-1)th antenna array 21 and its feeding network structure. That is, among the radiation modules 22-1, 22-2, . . . , 22-14, of the (2-2)th antenna array 22, in a sequential order, for example, the first to fourth radiation modules 22-1, 22-2, 22-3, and 22-4 are used for the third band, the 5th to 10th radiation modules 22-5, 22-6, 22-7, 22-8, 22-9, and 22-10 are used commonly for the second and third bands, and the 11st to 14th radiation modules 22-11, 22-12, 22-13, and 22-14 are used for the second band.
Further, for the radiation modules 22-1, 22-2, . . . , 22-14 of the (2-2)th antenna array 22 which are divided as described above, (2-2-1)th to (2-2-7)th power dividers 241 to 244, and (2-2-1)th, (2-2-2)th, and (2-2-3)th frequency combiners 641, 642, and 643 are provided.
The structures and operations of the multi-band antennas according to the foregoing embodiments of the present disclosure may be implemented as described above. While specific embodiments of the present disclosure have been described above, those skilled in the art will appreciate that the present disclosure may be carried out in other specific ways than those set forth herein without departing from the scope of the present disclosure.
For example, although it has been described above that a multi-band antenna of the present disclosure is provided with, for example, (2-1)th and (2-2)th antenna arrays in order to implement a MIMO antenna, the multi-band antenna may be configured to include, for example, only the (2-1)th antenna array in other embodiments of the present disclosure.
Also, while it has been described above that the radiation modules of the (2-1)th and (2-2)th antenna arrays, for example, are divided into three groups: a group for the second band, a group common for the second and third groups, and a group for the third band, the radiation modules of the (2-1)th and (2-2)th antenna arrays may be divided into two groups: a group for the second band and a group common for the second and third groups in other embodiments of the present disclosure. Obviously, the radiation modules of the (2-1)th and (2-2)th antenna arrays may also be divided into two groups: a group common for the second and third groups and a group for the third band.
Therefore, the scope of the present disclosure should be determined by the appended claims and their legal equivalents, not by the above description, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein. As described above, the multi-band antenna according to the present disclosure has an optimized structure and enables optimization of an antenna size, thereby facilitating antenna design and offering more stable characteristics.
Number | Date | Country | Kind |
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10-2013-0135481 | Nov 2013 | KR | national |
This application is a continuation of International Application No. PCT/KR2014/009829 filed on Oct. 20, 2014, which claims priority to Korean Application No. 10-2013-0135481 filed on Nov. 8, 2013, which applications are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/KR2014/009829 | Oct 2014 | US |
Child | 15147019 | US |