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KR20160114978A - Apparatus and System for beam forming of array antenna - Google Patents

Apparatus and System for beam forming of array antenna Download PDF

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Publication number
KR20160114978A
KR20160114978A KR1020150041555A KR20150041555A KR20160114978A KR 20160114978 A KR20160114978 A KR 20160114978A KR 1020150041555 A KR1020150041555 A KR 1020150041555A KR 20150041555 A KR20150041555 A KR 20150041555A KR 20160114978 A KR20160114978 A KR 20160114978A
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KR
South Korea
Prior art keywords
beams
base station
unit
mobile station
present
Prior art date
Application number
KR1020150041555A
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Korean (ko)
Inventor
이주열
김명돈
김진업
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한국전자통신연구원
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Priority to KR1020150041555A priority Critical patent/KR20160114978A/en
Publication of KR20160114978A publication Critical patent/KR20160114978A/en

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0408—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more beams, i.e. beam diversity
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
    • H04B7/0891—Space-time diversity
    • H04B7/0897—Space-time diversity using beamforming per multi-path, e.g. to cope with different directions of arrival [DOA] at different multi-paths

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Radio Transmission System (AREA)

Abstract

The present invention relates to a beamforming apparatus and system for a high directivity array antenna. The apparatus according to the present invention includes a beam number setting section for setting the number of beams of a mobile station (MS) using radio wave propagation characteristics and environmental parameters, a beam number setting section for setting a number of beams A beam generating unit for determining an antenna pattern by adjusting a weight of an element and generating a beam according to the determined antenna pattern, a beam generating unit for rotating the beam generated by the beam generating unit in at least one of a horizontal direction and a vertical direction a night search section for searching for a beam direction and a number of beams transmitted from a base station (BS) while the beam is rotated by the beam rotating section, and a beam search section for searching for a beam And a beam forming unit for performing beam forming according to the direction of the beam and the number of beams.

Figure P1020150041555

Description

[0001] The present invention relates to a beam forming apparatus and a system for a high directivity array antenna,

The present invention relates to a beamforming apparatus and system for a high directivity array antenna.

For the next generation (5G) mobile communication, it needs 1000 times data traffic capacity compared to the existing one. However, the radio waves transmitted from the transmitter are attenuated due to various factors such as free space loss, rainfall, atmosphere, building and terrain until reaching the receiver.

To compensate for this, the path loss can be reduced by using a highly directional antenna with high antenna gain. In order to change the direction of the antenna beam, the horn antenna must be physically turned. In the case of an array antenna, however, the antenna element the direction of the beam can be electrically adjusted by adjusting only the weight of the element.

Propagation in a frequency band higher than that of a microwave is limited by the number of scattering channels, so that the channel exhibits sparsity characteristics, and a line-of-sight (LoS) and a non-line-of-sight (NLoS) All show sparse distribution without distinction.

Therefore, if the beams are misaligned between the transmitting and receiving antennas, there is no reception power and communication link can not be established. Particularly, in a mobile communication environment, when the terminal and the surrounding environment are continuously changed, if the proper beam forming is not performed, the established communication link may be disconnected.

U.S. Published Patent Application No. 2014-0161105

An object of the present invention is to provide a beam forming apparatus and a system of a highly directional array antenna for precisely estimating and aligning a beam direction to a high directivity array antenna in a mobile communication system of a high frequency band to form a beam have.

The technical problems of the present invention are not limited to the above-mentioned technical problems, and other technical problems which are not mentioned can be understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided an apparatus including: a beam number setting unit configured to set a beam number of a mobile station (MS) using radio wave propagation characteristics and environment parameters; A beam generator for generating an antenna pattern according to the determined antenna pattern by adjusting the weights of the antenna elements according to the number of beams and for generating a beam according to the determined antenna pattern; A night search section for searching for a direction and a number of beams transmitted from a base station (BS) while the beam is rotated by the beam rotating section, And a beam forming unit for performing beam forming according to the direction of the beam and the number of beams detected by the searching unit.

According to the present invention, in a mobile communication system using a high-directional antenna with a high frequency band, the direction of the beam to the high-directional array antenna is accurately estimated and aligned so that the communication link is robust even when the communication propagation channel is sparse There is an advantage that it can be set and stably maintained.

1 is a diagram showing a configuration of a beam forming apparatus for a high directivity array antenna according to the present invention.
2 is a diagram showing an embodiment to be referred to in describing the beam number setting operation of the beam forming apparatus of the high directivity array antenna according to the present invention.
3 is a view illustrating an embodiment to be referred to in describing a weight setting operation of the beam forming apparatus of the high directivity array antenna according to the present invention.
4 and 5 are views showing an embodiment of the antenna pattern generated by the beam forming apparatus of the high directivity array antenna according to the present invention.
6 is a view showing an example of an operation for adjusting the beam directionality of the beam forming apparatus of the high directivity array antenna according to the present invention.
7 is a diagram showing a configuration of a beam forming system of a highly directional array antenna according to the present invention.
FIG. 8 is a flowchart illustrating an operation of performing beamforming in a beamforming system of a high directivity array antenna according to the present invention.
9 is a diagram illustrating an antenna pattern of a base station in a beamforming system of a high directivity array antenna according to the present invention.
FIGS. 10 to 12 are views illustrating an embodiment to be referred to in describing a beamforming operation of a base station in a beamforming system of a high directivity array antenna according to the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference numerals whenever possible, even if they are shown in different drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the difference that the embodiments of the present invention are not conclusive.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. Also, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagram referred to explain a configuration of a beam forming apparatus according to the present invention; FIG.

1, a beam forming apparatus according to the present invention includes a beam number setting unit 110, a beam generating unit 120, a beam rotating unit 130, a beam searching unit 140, and a beam forming unit 150 can do.

The beam number setting unit 110 sets the number of beams of a mobile station (MS). Here, the beam number setting of the mobile station acquires information such as delay, angular, and K-factor from the radio wave signal and utilizes it. At this time, the beam number setting unit 110 grasps the surrounding environment of the terminal by using radio propagation measurements data and environmental parameters of the GPS, acceleration sensor, gyro, etc. of the smart terminal, Set the number of beams according to the main propagation mechanism.

For example, the beam number setting unit 110 classifies the surrounding environment into a rural, a suburban, an urban, a dense urban, and an indoor, The number of beams can be set according to the required directivity level.

An embodiment of this can be represented as shown in FIG.

That is, as in Scenario 1 of FIG. 2, since the directional gain required in the rural is 'High', the number of beams can be set to 1 accordingly. Also, as in Scenario 2 of FIG. 2, since the directional gain required in suburban is 'High', the number of beams can be set to 1 to 2 accordingly.

Also, as in Scenario 3 of FIG. 2, since the directional gain required in the urban area is 'Medium', the number of beams can be set to 3 accordingly. Also, as in Scenario 4 of FIG. 2, since the directional gain required in a dense urban area is 'Low', the number of beams can be set to 4 accordingly.

Also, as in Scenario 5 of FIG. 2, since the directional gain required in indoor is 'Low', the number of beams can be set to 3 accordingly. Here, although the directional gain required in the scenario 5 is 'Low' as in dense urban areas, it is possible to set the number of beams to be smaller than the dense urban area in consideration of the fact that the directional gain is indoors.

Of course, the embodiment for setting the number of beams is not limited to any one, and it is obvious that various embodiments are applicable.

The beam generating unit 120 generates a beam corresponding to the number of beams set by the beam number setting unit 110. At this time, the beam generator 120 adjusts an array antenna pattern to perform MS beam generation. An embodiment for adjusting the antenna pattern of the array antenna can be shown in Fig.

The beam generator 120 may adjust the weight of the antenna element of the array antenna, as shown in FIG. As an example, the beam generator 120 may calculate the weights w 1 , w 2 , w 3 , w 4 , ... of the respective antenna elements. w K , respectively.

At this time, it is assumed that the number of beams M to be generated and the number N of antennas satisfy 'M? N - 1'. However, it is a matter of course that the number of beams according to the number of antennas may be varied according to the embodiment.

The beams generated by the beam generator 120 may implement various beam patterns according to the number of beams. An embodiment of the beam pattern according to the number of beams can be represented as shown in FIG.

Referring to FIG. 4, if the number of beams is one, the beam generating unit 120 may generate a beam pattern having one directionality as shown in reference numeral 411. FIG. In addition, if the number of beams is two, the beam generating unit 120 may generate a beam pattern having a two-directional shape as indicated by reference numeral 412.

Also, the beam generator 120 can generate beam patterns of three directional shapes as indicated by reference numeral 413 when the number of beams is three. In addition, if the number of beams is four, the beam generating unit 120 may generate beam patterns of four directional shapes as indicated by reference numeral 414.

In this manner, when the number of beams is K, the beam generating unit 120 can generate beam patterns having K directionality. At this time, each of the generated beams has a beam ID assigned thereto .

The beam rotation unit 130 has a magnitude component and a phase component as complex numbers and the weight of the array antenna has a phase component. The beam rotation unit 130 rotates the beam generated by the beam generation unit 120 by adjusting the complex number phase component of the weight . At this time, the beam rotating unit 130 may rotate the beam in the horizontal direction and / or the vertical direction. Here, the beam search unit 140 may search for the beam direction and the number of beams transmitted from the base station (BS) while the beam rotation unit 130 rotates the beam.

The beam search operation is aimed at link setup. Therefore, the beam rotating unit 130 rotates the beam after setting the directivity to such an extent that the link is established rather than making the beam of the multiple antennas sharp. At this time, As shown in FIG.

Here, if the link margin is insufficient, the beam of the base station may not be searched even if the beam of the mobile station is rotated. If the beam search unit 140 does not search for the beam of the base station while the beam is rotating, the number of beams of the array antenna is reduced to increase the directivity in order to increase the gain of the array antenna.

In other words, the beam generating unit 120 adjusts the number M of beams to M-1 to generate beams, and thereafter, the beam scanning unit 140 rotates M-1 beams in the beam rotating unit 130 Thereby searching for the beam of the base station. In this case, if the beam of the base station is not detected, M can be adjusted to M-2, M-3, .., and the beam of the base station can be searched.

In the mobile communication environment, since the terminal environment and the surrounding environment change instantaneously, the beam search unit 140 performs beam searching as much as possible to utilize the resources of the terminal as information about beamforming. For example, the beam search unit 140 may search for a beam using resources that are not transmitted or received, such as extra RF, DTX (Discontinuous Transmission) section, DRX (Discontinuous Reception) section, or the like.

If the beam search unit 140 searches for the beam of the base station, the beam forming unit 150 aligns the beam of the base station and the beam of the mobile station so that they are aligned with each other, Thereby performing beam forming.

FIG. 7 is a diagram illustrating a wireless communication system to which a beam forming apparatus according to the present invention is applied. 7, a beam forming operation between a base station and a mobile station will be described.

First, the beamforming of the mobile station 100 is performed after the beamforming of the base station 200 is performed first.

The mobile station 100 measures a characteristic value of a beam signal received from the base station 200 and outputs a candidate beam (hereinafter, referred to as a " candidate beam can be selected. Here, the mobile station 100 transmits the number and ID of the beam corresponding to the candidate beam to the base station 200, and the base station 200 performs beamforming based on the information of the candidate beam received from the mobile station 100 do.

When the beamforming of the base station 200 is completed, the mobile station 100 searches for a beam that receives the beam of the base station 200 and performs beamforming.

A detailed description of the beamforming operation of the base station 200 and the mobile station 100 will be described in more detail with reference to the embodiment of FIG.

Referring to FIG. 8, the base station 200 broadcasts a plurality of beam signals through the downlink at the transmitting terminal 201 (S110). Here, the base station 200 generates a beam according to the number of available beams in the base station 200 for beamforming of the base station 200.

At this time, the beam pattern by the base station 200 can be represented as shown in FIG. As shown in FIG. 9, the base station 200 transmits the ID of the beam given in the order of beams in the direction of each beam.

The mobile station 100 can receive the beam signal broadcasted by the receiving end 105. [ At this time, the mobile station 100 can estimate the direction of the beam signals received from the base station 200 and estimate the ID of the corresponding beam.

An embodiment for estimating the ID of the beam signal of the base station 200 in the mobile station 100 is described with reference to FIG.

10, the base station 200 firstly estimates the direction of the beam using an algorithm for estimating the direction of the beam received from the base station 200, for example, a direction of arrival (DOA) estimation algorithm . At this time, the base station 200 can remove the first-order estimated direction component from the received beam signal and estimate the direction of the secondary beam.

This is to estimate the direction of the beam using the sparsity, which is the propagation characteristic of the high directional antenna in the high frequency band. In this case, by sequentially removing the beams, it is possible to minimize the influence of the component having a large beam power when estimating the beam direction of the component having a small beam power.

In addition, the mobile station 100 may measure characteristic values of a plurality of beam signals received from the base station 200 (S120), and may select a candidate beam. At this time, the mobile station 100 can set a beam having a signal level higher than the reference signal as a candidate beam.

11, when the mobile station 100 receives a signal through the signal path 1 and the signal path 2, only the signal path 1 is at the minimum signal level in the A region Therefore, the signal of signal path 1 can be set as a candidate beam.

Since the signal path 1 and the signal path 2 are both at the lowest signal level or higher in the B region, the mobile station 100 sets either a signal path 1 or a signal path 2 as a candidate beam or both signals as a candidate beam have.

On the other hand, in the C region, signal path 2 can be set as the candidate beam because the signal path 2 is the minimum signal level.

Here, the mobile station 100 sets the number of candidate beams according to the surrounding environment (e.g., center, sub-center, country, etc.) for link establishment of the communication link (S130).

Here, an example of setting the number of candidate beams according to the surrounding environment will be described with reference to FIG. That is, as in the scenario 1 of FIG. 12, the mobile station 100 can set the number of beams required by the base station 200 to 1 in case of rural, the number of beams required by the base station 200 can be set to 1 to 2.

In addition, when the mobile station 100 is in an urban area such as a scenario 3 in FIG. 12 or in an indoor area such as a scenario 5, the number of beams required in the base station 200 is set to 3 The number of beams required in the base station 200 can be set to four in case of a dense urban area such as a scenario 4.

At this time, the mobile station 100 transmits information on the selected candidate beam, for example, the ID information of the candidate beam to the base station 200 through the uplink (S140).

The receiving end 205 of the base station 200 transmits the information about the candidate beam received from the mobile station 100 to the transmitting end 201. At this time, the receiving end 205 transmits the information about the candidate beam to the transmitting end 201 through the feedback channel of the base station 200.

The base station 200 determines the beam signal of the antenna based on the information of the candidate beam selected from the mobile station 100, schedules the radio resource (S150), and transmits the ID information of the corresponding beam to the mobile station 100 (S160).

At this time, the mobile station 100 performs beamforming of the base station 200 based on the beam signal transmitted from the base station 200 (S170). The beamforming of the base station 200 allows the mobile station 100 to set a candidate beam according to the surrounding environment (the center, the subcenters, and the rural areas) in order to establish a communication link.

In order to improve communication performance such as BER and capacity, the beamforming of the mobile station 100 is performed by using the main lobe of the beam of the base station 200 and the main lobe of the beam of the mobile station 100, And a fine-tuning procedure to match the wavelength of the light. At this time, the number of beams of the base station 200 and the number of beams of the mobile station 100 do not necessarily have to be the same.

The base station 200 can continuously transmit data while performing the beamforming in the base station 200 in step S180 and receive a response signal from the base station 200 in step S190.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention.

Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: mobile station (MS) 101: transmitting terminal (TX)
105: receiving end (RX) 10: beam number setting unit
120: beam generating unit 130: beam rotating unit
140: beam search unit 150: beamforming unit
200: base station (BS) 201: transmitting terminal (TX)
205: Receiver (RX)

Claims (1)

A beam number setting unit for setting the number of beams of a mobile station (MS) using radio wave propagation characteristics and environmental parameters;
A beam generator for determining an antenna pattern by adjusting a weight value of each antenna element according to the number of beams set by the beam number setting unit, and generating a beam according to the determined antenna pattern;
A beam rotating unit for rotating the beam generated by the beam generating unit in at least one of a horizontal direction and a vertical direction;
A beam search unit for searching for a beam direction and a number of beams transmitted from a base station (BS) while the beam is rotated by the beam rotating unit; And
A beam forming unit for performing beam forming according to the direction of the beam detected by the beam searching unit and the number of beams,
Wherein the beam forming apparatus comprises:
KR1020150041555A 2015-03-25 2015-03-25 Apparatus and System for beam forming of array antenna KR20160114978A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101958163B1 (en) * 2019-01-02 2019-07-04 알에프코어 주식회사 Beamformer including signal detector for compensating weights, wireless transmitting and receiving device including beamformer, and operating method of wireless transmitting and receiving device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101613699B1 (en) 2014-11-18 2016-04-19 에이스기계 주식회사 Packing case

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101613699B1 (en) 2014-11-18 2016-04-19 에이스기계 주식회사 Packing case

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101958163B1 (en) * 2019-01-02 2019-07-04 알에프코어 주식회사 Beamformer including signal detector for compensating weights, wireless transmitting and receiving device including beamformer, and operating method of wireless transmitting and receiving device
US10784937B2 (en) 2019-01-02 2020-09-22 Rfcore Co., Ltd. Beamformer including signal detector for compensating weights, wireless transmitting and receiving device including beamformer, and operating method of wireless transmitting and receiving device including beamformer

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