KR101760411B1 - Apparatus and method of hybrid beamforming - Google Patents

Abstract

The present invention relates to a wireless communication system including a plurality of antenna arrays that support data communication with a plurality of terminals and each of which includes a plurality of antennas and at least one of the plurality of antennas is an active antenna, 130 and a processor for executing the program. At this time, the processor calculates the signal-to-noise ratio corresponding to the beamformed signal to the terminal by the antenna array according to the execution of the program, compares the calculated signal-to-noise ratio and a predetermined decoding threshold value, And increases the number of active antennas among the plurality of antennas included in each antenna array until the calculated signal-to-noise ratio exceeds the decoding threshold.

Description

[0001] APPARATUS AND METHOD OF HYBRID BEAMFORMING [0002]

The present invention relates to a hybrid beamforming apparatus and method.

A massive multiple-input multiple-output (MIMO) system is a smart antenna technology for increasing the capacity of wireless communication, and can support multiple users' terminals simultaneously through a single wireless communication base station in a user-concentrated area. The giant array MIMO system includes a plurality of antennas capable of beamforming signals to a plurality of user terminals.

In a Gigabit Arrays MIMO system, a plurality of antennas are used in order to reduce signal loss due to a state connected to one or more UEs. That is, a terminal connected to a giant array multi-input / output (I / O) system can receive and beam-form a beamformed signal from a plurality of antennas and perform data communication. Therefore, the terminal can receive high quality wireless communication service with high quality of service through the large array multi input / output system. However, as the giant array multi-input / output system uses a plurality of antennas, the power consumption can also be increased. Also, since the number of analog / digital and digital / analog log converters according to a plurality of antennas is increased in a giant array multiple input / output system, resource usage included in the giant array multiple input / output system can be increased.

As a conventional invention for solving such a problem, Korean Patent Laid-Open Publication No. 10-2014-0128399 (entitled " Hybrid Beamforming Based Open Route MIMO Transmission Method and Apparatus ") discloses a transmitter including a plurality of transmit antennas A method for transmitting / receiving a signal for determining system information including a correspondence relationship between a transmission resource and each transmission antenna, transmitting a signal to a receiver based on determined system information, and receiving feedback information on the signal transmission from a receiver have.

It is an object of the present invention to provide a hybrid beam forming apparatus and method for progressively changing the number of active antennas based on a signal-to-noise ratio.

It should be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

According to a first aspect of the present invention, there is provided a hybrid beamforming apparatus including a plurality of antennas for supporting data communication with each of a plurality of terminals, Includes a plurality of antenna arrays configured with active antennas, a memory storing a program supporting hybrid beamforming, and a processor executing a program. At this time, the processor calculates the signal-to-noise ratio corresponding to the beamformed signal to the terminal by the antenna array according to the execution of the program, compares the calculated signal-to-noise ratio and a predetermined decoding threshold value, And increases the number of active antennas among the plurality of antennas included in each antenna array until the calculated signal-to-noise ratio exceeds the decoding threshold.

A hybrid beamforming method performed by a hybrid beamforming apparatus according to a second aspect of the present invention includes the steps of: calculating a signal-to-noise ratio corresponding to a beamformed signal to a terminal by an antenna array; Comparing the calculated signal-to-noise ratio and a predetermined decoding threshold value through the calculating step; And increasing the number of active antennas of the plurality of antennas included in each antenna array until the calculated signal-to-noise ratio exceeds a decoded threshold, according to a result of the comparing step. At this time, the antenna array supports data communication with each of a plurality of terminals, and includes a plurality of antennas, and at least one of the plurality of antennas is configured with an active antenna.

According to any one of the above-mentioned problems, the present invention can gradually change the number of antennas of a sub-array connected to a terminal so that the signal-to-noise ratio satisfies a minimum decoding threshold value. In addition, the number of active antennas can be set differently according to the connection state of each terminal connected to a plurality of sub-arrays.

Accordingly, the present invention can allocate a large number of antennas to a terminal having a poor connection state, and allocate a small number of antennas to a terminal having a good connection state. That is, although the conventional hybrid beamforming apparatus of the multi-input multiple output scheme fixedly uses more than 100 antennas, the present invention can use only a minimum number of antennas that can achieve satisfactory performance. The present invention can minimize the loss of a signal according to the connection state of a connected terminal, and can reduce resource overhead and power consumption due to unnecessary use of an antenna.

1 is a block diagram of a hybrid beamforming apparatus according to an embodiment of the present invention.
FIG. 2 and FIG. 3 are views for explaining an activation process of an antenna in a hybrid beam forming apparatus according to an embodiment of the present invention.
4 is an illustration of an active antenna for each sub-array in a hybrid beamforming apparatus according to an embodiment of the present invention.
5 is a flowchart of a hybrid beamforming method performed by a hybrid beamforming apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly explain the present invention in the drawings, parts not related to the description are omitted.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when a part is referred to as "including " an element, it does not exclude other elements unless specifically stated otherwise.

Next, the hybrid beam forming apparatus 100 will be described with reference to Figs.

1 is a block diagram of a hybrid beamforming apparatus 100 according to an embodiment of the present invention.

The hybrid beam forming apparatus 100 performs wireless data communication with a plurality of terminals 150 through a plurality of subarrays 110 included in the hybrid beam forming apparatus 100. At this time, the hybrid beamforming apparatus 100 may be a wireless communication base station or a wireless communication system.

The hybrid beamforming apparatus 100 includes a plurality of sub-arrays 110, a memory 130, and a processor 140.

The sub-arrays 110 are present in at least one or more numbers and may constitute a main array (not shown).

The sub-array 110 also supports wireless data communication with the terminal 150. The sub-array 110 means an antenna array composed of a plurality of antennas 120 including at least one active antenna. At this time, the plurality of antennas 120 included in the sub-array 110 may be linearly arranged along a straight line, and may be disposed on a plane such as a circular or rectangular shape, but the present invention is not limited thereto.

For it is possible to contain, l antenna 120 perform the m number of sub-array 110, data communication and hybrid beam forming device 100 is the maximum m number of the terminal 150 including the consisting of each (l, m ≥ 1) . In addition, the terminal 150 can perform wireless data communication using at least one antenna of the active l antenna 120 of the terminal 150 and the communication unit with a random array 110 is connected.

The memory 130 stores a program that supports hybrid beamforming. At this time, the memory 130 may be referred to as a non-volatile storage device that keeps stored information even when power is not supplied, and a volatile storage device that requires power to maintain stored information.

The processor 140 is configured to perform a signal-to-noise ratio corresponding to the beamformed signal to the terminal 150 by the sub-array 110, according to the execution of a program that supports the hybrid beamforming stored in the memory 130. [ noise ratio (SNR). At this time, the signal-to-noise ratio can be calculated as a relative signal power magnitude based on the magnitude of the power to noise relative to the power to signal.

The processor 140 compares the calculated signal-to-noise ratio and a predetermined decoding threshold value. As a result of the comparison, the processor 140 gradually increases the number of the active antennas 120 among the plurality of antennas 120 included in the sub-array 110 until the calculated signal-to-noise ratio exceeds the decryption threshold .

For example, if one of the l antennas is active and the signal-to-noise ratio is below the decoding threshold, the processor 130 may activate any one of the deactivated ( l -1) have. That is, there are two active antennas, and ( 1 - 2) inactivated antennas.

The processor 140 may incrementally increase the number of active antennas by a predetermined number. For example, if the predetermined number is one, the processor 140 may switch one deactivated antenna to the active state each time the number of active antennas is increased. In addition, if the predetermined number is two, the processor 140 can switch the two inactive antennas to the active state each time the number of activated antennas is increased.

In addition, the predetermined number may be set differently for each sub-array 110. For example, if the predetermined number of the first sub-arrays is one and the predetermined number of the second sub-arrays is two, the processor 140 activates the deactivated antenna according to a predetermined number in each sub-array State. The specific antenna activation process will be described with reference to FIG. 2 and FIG.

FIGS. 2 and 3 are exemplary diagrams illustrating an activation process of the antenna 120 in the hybrid beamforming apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 2, the first terminal 250 may perform data communication through the first antenna 210 among the plurality of antennas included in the first sub-array 200. First, the processor 140 may calculate the signal-to-noise ratio corresponding to the beamformed signal by the first sub-array 200. [ That is, the processor 140 may calculate the signal-to-noise ratio corresponding to the beamformed signal using only the first antenna 210. [

In addition, the processor 140 may compare the calculated signal-to-noise ratio with the decoding threshold. If the calculated signal-to-noise ratio exceeds the decoding threshold, the processor 140 determines that the strength of the signal for the first terminal 250 is sufficient with only the first antenna 210, It may not be activated. Therefore, the first terminal 250 can perform decoding on the beamformed signal through the first antenna 210. [

However, if the calculated signal-to-noise ratio is less than the decoding threshold, the processor 140 switches the predetermined number of antennas of the second antenna 220 to the fourth antenna 240, which are inactivated antennas, can do.

To this end, the processor 140 may calculate a received signal strength indicator (RSSI) corresponding to each of the deactivated antennas. Then, the processor 140 can select an antenna to be activated in the ascending order of the calculated radio signal strength. At this time, a program for measuring the radio signal strength of each antenna and selecting an antenna having a large radio signal intensity and activating it first may be programmed in advance and stored in the memory 130. Thus, the processor 140 may execute a program stored in the memory to select one of the one or more deactivated antennas to transition to the active state.

3, when the predetermined number is one and the second antenna 220 among the second to fourth antennas 220 to 240 has the highest radio signal intensity, (220) to be in the active state, and to switch the selected antenna to the active state.

When the deactivated antenna is activated, the processor 140 may reassemble the signal-to-noise ratio for the beamformed signals of the first antenna 210 and the second antenna 220 in the active state. The processor 140 may then compare the recalculated signal-to-noise ratio with the decoding threshold. According to the result of the comparison, the processor 140 switches the third antenna 230 and the fourth antenna 240, which are inactivated antennas, to the active state, or supports decoding of the beamformed signal at the terminal 150 Can be performed.

4 is an exemplary view of an active antenna according to a subarray in the hybrid beamforming apparatus 100 according to an embodiment of the present invention.

As described above, the processor 140 can convert the deactivated antenna into an active state until the signal-to-noise ratio of each of the plurality of subarrays 110 becomes equal to or higher than a decoding threshold value. At this time, depending on the state between the terminal 150 and the hybrid beamforming apparatus 100, the number of active antennas of each of the plurality of sub-arrays 110 may be different.

Referring to FIG. 4, in the first sub-array 400 connected to the first terminal 420, three of the four antennas are active. In addition, only one of the four antennas is active in the second sub-array 430 connected to the second terminal 450. The hybrid beamforming apparatus 100 according to an embodiment of the present invention includes a sub-array 110 connected in communication with a corresponding terminal 150 so that a signal-to-noise ratio with the terminal 150 may satisfy a minimum decoding threshold. The number of active antennas can be adjusted. Therefore, the number of active antennas of the sub-array 110 corresponding to each terminal 150 may differ depending on the state of each terminal 150.

The processor 140 may then support decoding of the beamformed signal by the active antenna at the terminal 150 if no more inactive antennas are present or the signal-to-noise ratio is greater than or equal to the decoding threshold.

Meanwhile, the hybrid beamforming apparatus according to another embodiment of the present invention calculates the signal-to-noise ratio corresponding to the beamformed signal to the terminal by the sub-array, and based on the calculated signal-to-noise ratio, The number can be gradually reduced.

More specifically, in a hybrid beamforming apparatus according to another embodiment of the present invention, when the calculated signal-to-noise ratio exceeds a decoding threshold, the processor calculates a radio signal strength of a plurality of antennas activated in advance, One or more of the plurality of antennas activated in the weak order can be inactivated. The processor may also recalculate the signal-to-noise ratio and transition the deactivated antenna to a deactivated state gradually until the re-computed signal-to-noise ratio is below the decoding threshold.

Next, a hybrid beamforming method performed by the hybrid beamforming apparatus 100 according to an embodiment of the present invention will be described with reference to FIG.

5 is a flowchart of a hybrid beamforming method performed by the hybrid beamforming apparatus 100 according to an embodiment of the present invention.

First, the hybrid beamforming apparatus 100 may calculate the signal-to-noise ratio corresponding to the beamformed signal to the terminal 150 by the sub-array 110 (S500). At this time, the sub-array 110 supports wireless data communication with each of the plurality of terminals 150, and includes a plurality of antennas 120. At least one of the plurality of antennas 120 included in the sub-array 110 is in an activated state.

The hybrid beamforming apparatus 100 compares the calculated signal-to-noise ratio and a predetermined decoding threshold value (S510).

The hybrid beamforming apparatus 100 then calculates the number of active antennas 120 among the plurality of antennas 120 included in each sub-array 110 until the calculated signal-to-noise ratio exceeds the decoded threshold value, (S520).

Specifically, the hybrid beamforming apparatus 100 may perform decoding on the beamformed signal through the pre-activated antenna if the calculated signal-to-noise ratio exceeds the decoding threshold.

In contrast, if the calculated signal-to-noise ratio is less than or equal to the decoding threshold, the hybrid beamforming apparatus 100 may switch one or more of the one or more deactivated antennas included in the sub-array 110 to an active state. At this time, the antenna that is switched to the active state may be selected based on the radio signal strength of one or more inactive antennas included in the sub-array 110.

The hybrid beamforming apparatus 100 may increase the number of active antennas 120 and then estimate the signal-to-noise ratio corresponding to the beamformed signal.

The hybrid beamforming apparatus 100 can perform a comparison between the re-calculated signal-to-noise ratio and the decoding threshold value.

If the re-computed signal-to-noise ratio exceeds the decoding threshold, the hybrid beamforming apparatus 100 may perform decoding on the beamformed signal through the previously-activated antenna 120.

If the re-computed signal-to-noise ratio is less than or equal to the decoding threshold, the hybrid beamforming apparatus 100 determines whether the signal-to-noise ratio is greater than or equal to a decoding threshold, It is possible to switch any one or more of the deactivated antennas to the active state.

The hybrid beamforming apparatus 100 and method according to an embodiment of the present invention may incrementally change the number of antennas of the subarray 110 that is in communication with the terminal 150 so that the signal to noise ratio satisfies the minimum decoding threshold . In addition, the hybrid beamforming apparatus 100 and method may set the number of active antennas to be different depending on the connection state of each terminal 150 communicatively coupled to the plurality of sub-arrays 110.

Therefore, the hybrid beamforming apparatus 100 and method can allocate a large number of antennas to a terminal having a poor connection state, and allocate a small number of antennas to a terminal having a good connection state. That is, although the hybrid beam forming apparatus of the conventional giant array multi-input / output scheme uses more than 100 antennas, the hybrid beam forming apparatus 100 and the method can use only the minimum number of antennas satisfying the satisfactory performance. The hybrid beamforming apparatus 100 and method can minimize the loss of a signal according to the connection state of the communication terminal 150, reduce power consumption due to unnecessary use of the antenna, and reduce power consumption.

One embodiment of the present invention may also be embodied in the form of a recording medium including instructions executable by a computer, such as program modules, being executed by a computer. Computer readable media can be any available media that can be accessed by a computer, and includes both volatile and nonvolatile media, removable and non-removable media. Further, the computer-readable recording medium may include all computer storage media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

While the methods and systems of the present invention have been described in connection with specific embodiments, some or all of those elements or operations may be implemented using a computer system having a general purpose hardware architecture.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Hybrid beam forming apparatus
110: sub array
120: antenna
130: memory
140: Processor
150: terminal

Claims (11)

In the hybrid beam forming apparatus,
A plurality of antenna arrays connected to each of the plurality of terminals to support wireless data communication of the connected terminals and including a plurality of antennas, at least one of the plurality of antennas being an active antenna,
A main array including the plurality of antenna arrays,
Programs that support hybrid beamforming are stored in memory and
And a processor for executing the program,
Wherein the processor calculates a signal-to-noise ratio corresponding to a beamformed signal at a terminal connected to the antenna array according to execution of the program, compares the calculated signal-to-noise ratio and a predetermined decoding threshold value,
Selecting an antenna to be switched to an active state based on a signal-to-noise ratio of one or more deactivated antennas included in the antenna array according to the result of the comparison, Increasing the number of active antennas among the plurality of antennas included in each antenna array,
Each sub-array supports wireless data communication for one terminal, determines the number of active antennas for a terminal connected thereto,
Wherein the number of active antennas for each subarray can be set differently according to a state between the plurality of terminals and the hybrid beamforming apparatus. The method according to claim 1,
Wherein the processor switches one or more of the one or more deactivated antennas included in the antenna array to an active state if the calculated signal-to-noise ratio is below the predetermined decryption threshold. The method according to claim 1,
The processor re-calculates the signal-to-noise ratio corresponding to the beamformed signal after activating the deactivated antenna, performs a comparison between the re-calculated signal-to-noise ratio and the decoding threshold value, And switches one or more of the one or more deactivated antennas included in the antenna array to an active state until the signal-to-noise ratio is greater than or equal to the predetermined decryption threshold. delete The method according to claim 1,
Wherein the processor sets different numbers of active antennas to be added for each antenna array when the calculated signal-to-noise ratio is equal to or smaller than the decoding threshold value. In a hybrid beamforming method performed by a hybrid beamforming apparatus,
Calculating a signal-to-noise ratio corresponding to the beamformed signal to the terminal by the antenna array for a terminal connected to the antenna array;
Comparing the calculated signal-to-noise ratio and a predetermined decoding threshold value through the calculating step; And
And increasing the number of active antennas of the plurality of antennas included in each antenna array until the calculated signal-to-noise ratio exceeds the decoded threshold, according to a result of the comparing step,
Wherein the antenna array is included in a main array, supports wireless data communication of the terminal, and includes a plurality of antennas, at least one of the plurality of antennas being an active antenna,
The main array includes a plurality of antenna arrays each connected to a terminal
Wherein increasing the number of active antennas comprises:
Selecting an antenna to switch to an active state based on a signal-to-noise ratio of at least one inactive antenna included in the antenna array; And
And switching the selected antenna to an active state,
Each sub-array supports wireless data communication for one terminal, determines the number of active antennas for a terminal connected thereto,
Wherein the number of active antennas for each subarray can be set differently according to a state between the plurality of terminals and the hybrid beamforming apparatus. The method according to claim 6,
The step of increasing the number of active antennas
And switches at least one of the one or more deactivated antennas included in the antenna array to an active state if the calculated signal-to-noise ratio is below the predetermined decryption threshold. The method according to claim 6,
After increasing the number of active antennas,
Estimating a signal-to-noise ratio corresponding to the beamformed signal;
Performing a comparison of the recalculated signal-to-noise ratio and the decoding threshold value through the step of delivering the property; And
Further comprising switching one or more of the one or more deactivated antennas included in the antenna array to an active state until the recomputed signal to noise ratio is greater than or equal to the predetermined decryption threshold, Way. delete The method according to claim 6,
Wherein increasing the number of active antennas comprises:
And sets the number of active antennas to be added for each antenna array to be different when the calculated signal-to-noise ratio is equal to or less than the decoding threshold value. A computer-readable recording medium recording a program for performing the method according to any one of claims 6 to 8 and 10 on a computer.

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