Communication method and device using beamforming in wireless communication system

Patent metadata

Field	Value
Publication number	US-2016006122-A1
Application number	US-201314418902-A
Country	US
Kind code	A1
Filing date	Jul 31, 2013
Priority date	Jul 31, 2012
Publication date	Jan 7, 2016
Grant date	—

Abstract

A communication method and device using beamforming in a wireless communication system are disclosed. A base station determines according to a predetermined trigger condition and a channel state of a terminal whether to enable a beam overlap mode using an overlap beam in which a plurality of unitary beams of the base station are overlapped, selects one or more best beams from among the plurality of unitary beams if it is determined that the beam overlap mode is not enabled, and transmits or receives a signal for the terminal through the selected best beams. If it is determined that the beam overlap mode is enabled, the base station forms the overlap beam in which the plurality of unitary beams of the base station are overlapped by adjusting beamforming coefficients of a beamforming unitary and transmits or receives a signal for the terminal through the overlap beam.

First claim

1 . A method for transmitting a signal using beamforming in a wireless communication system, the method comprising:
determining whether to enable a beam superposition mode using a superposed beam generated by superposing a plurality of unitary beams of a first node according to a predetermined trigger condition and a channel state of a second node; selecting one or more best beams from the plurality of unitary beams after determining not to enable the beam superposition mode; transmitting a signal for the second node through the selected best beam; controlling a beamforming unit of the first node to form a superposed beam generated by superposing the plurality of unitary beams after determining to enable the beam superposition mode; and transmitting the signal for the second node through the superposed beam.

2 . The method of claim 1 , further comprising transmitting beam superposition mode information indicating the predetermined trigger condition to the second node, wherein the predetermined trigger condition includes at least one of:
a beam superposition allocation threshold indicating a threshold of a channel quality measurement of an individual unitary beam for determining a transition to the beam superposition mode, a beam superposition release threshold indicating a threshold of a channel quality measurement of an individual unitary beam, a beam superposition allocation timer indicating a minimum time required for measuring channel quality for a trigger event of the beam superposition mode, a beam superposition release timer indicating a minimum time required for measuring channel quality for a release event of the beam superposition mode, and a maximum number of beams supported for superposition indicating a maximum number of adjacent beams which can simultaneously support a mobile station (MS) through beam superposition.

3 . The method of claim 1 , wherein determining whether to enable the beam superposition mode comprises:
determining whether the first node determines the beam superposition mode for the second node; determining whether enabling or disabling of the beam superposition mode is requested from the second node according to the trigger condition; and determining whether to enable the beam superposition mode according to at least one of whether the first node determines the beam superposition mode for the second node or whether enabling or disabling of the beam superposition mode is requested from the second node according to the trigger condition.

4 . The method of claim 1 , further comprising:
when there is a determination to enable the beam superposition mode, receiving information on a number M of adjacent beams which satisfies a predetermined threshold from the second node; receiving channel quality information (CQI) of M adjacent unitary beams from the second node; and performing link adaptation and burst scheduling for the M adjacent unitary beams based on the CQI.

5 . The method of claim 1 , further comprising:
making a determination to enable a beam superposition mode of unit reception beams of the first node; estimating information on a number M of adjacent unit reception beams having channel measurements larger than a predetermined threshold, and measuring or estimating channel quality information (CQI) of the M adjacent unit reception beams; and performing link adaptation and burst scheduling for the M adjacent unit reception beams based on the CQI.

6 . The method of claim 1 , further comprising:
making a determination to enable a beam superposition mode of unit transmission beams of the second node; estimating information on a number N of adjacent unit transmission beams of the second node having channel measurements larger than a predetermined threshold, and measuring or estimating CQI of the number N adjacent unit transmission beams; performing link adaptation and burst scheduling for the number N adjacent unit transmission beams based on the CQI; and transmitting results of the link adaptation and the burst scheduling for the number N adjacent unit transmission beams to the second node.

7 . The method of claim 1 , wherein the plurality of unitary beams superposed includes one unitary beam having the highest channel quality for the second node among the plurality of unitary beams of the first node, and unitary beams adjacent to the one unitary beam.

8 . The method of claim 1 , wherein a maximum number of unitary beams which can be used for forming the superposed beam is limited to a number of radio frequency (RF) paths included in the first node.

9 . A signal transmitting apparatus for transmitting a signal using beamforming in a wireless communication system, the apparatus comprising:
a beamforming controller configured to:
determine whether to enable a beam superposition mode using a superposed beam generated by superposing a plurality of unitary beams of a first node according to a predetermined trigger condition and a channel state of a second node,
select one or more best beams from the plurality of unitary beams after determining not to enable the beam superposition mode, and
control beamforming coefficients when there is a determination to enable the beam superposition mode; and
a transceiver configured to:
transmit or receive a signal for the second node through the selected best beam,
form a superposed beam generated by superposing the plurality of unitary beams according to the beamforming coefficients, and
transmit a signal for the second node through the superposed beam.

10 . A method for receiving a signal using beamforming in a wireless communication system, the method comprising:
determining whether to enable a beam superposition mode of a first node using a superposed beam generated by superposing a plurality of unitary beams of the first node according to a predetermined trigger condition and a channel state measured by a second node; measuring channel qualities of the plurality of unitary beams of the first node and selecting one or more best beams based on the channel quality measurements when there is a determination not to enable the beam superposition mode; reporting a first channel quality information (CQI) indicating a channel quality measurement of the selected best beam to the first node; estimating an overall channel quality measurement of a predetermined number of adjacent unitary beams when there is a determination to enable the beam superposition mode; and reporting a second CQI indicting the overall channel quality measurement of the adjacent unitary beams to the first node.

11 . The method of claim 10 , further comprising receiving beam superposition mode information indicating the predetermined trigger condition from the first node, wherein the predetermined trigger condition includes at least one of:
a beam superposition allocation threshold indicating a threshold of a channel quality measurement of an individual unitary beam for determining a transition to the beam superposition mode, a beam superposition release threshold indicating a threshold of a channel quality measurement of an individual unitary beam, a beam superposition allocation timer indicating a minimum time required for measuring channel quality for a trigger event of the beam superposition mode, a beam superposition release timer indicating a minimum time required for measuring channel quality for a release event of the beam superposition mode, and a maximum number of beams supported for superposition indicating a maximum number of adjacent beams which can simultaneously support a mobile station (MS) through beam superposition.

12 . The method of claim 10 , wherein determining w

Assignees

• Samsung Electronics Co Ltd

Inventors

• Seol Ji-Yun
• Kim Tae-Young

Classifications

• H04B7/0617 Primary

  for beam forming · CPC title

• H04L1/06

  using space diversity · CPC title

• H04L1/0006

  by adapting the transmission format · CPC title

• H01Q3/30 Primary

  varying the {relative} phase {between the radiating elements of an array (H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence)} · CPC title

• H04L1/0026

  Transmission of channel quality indication · CPC title