Method and apparatus for transmitting and receiving reference signal in mobile communication system using beamforming

Patent metadata

Field	Value
Publication number	US-9960839-B2
Application number	US-201313903612-A
Country	US
Kind code	B2
Filing date	May 28, 2013
Priority date	May 25, 2012
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A method for transmitting a reference signal by a Base Station (BS) in a mobile communication system using beamforming includes determining beamforming information for transmission of a Reference Signal (RS) Transmit (Tx) beam, wherein at least one of a Tx period and a beam width of the RS Tx beam is determined differently based on a size of Receive (Rx) areas in which a plurality of Tx beams are received in coverage of the BS; and transmitting the RS Tx beam to related Rx areas depending on the determined beamforming information.

First claim

What is claimed is:

1. A method for transmitting a reference signal (RS) by a base station (BS) in a mobile communication system using beamforming, the method comprising:
determining beamforming information for transmission of a RS transmit (Tx) beam which is used for identifying an optimal data Tx beam by a mobile station (MS), wherein the beamforming information includes at least one of a Tx period and a beam width of the RS Tx beam which is determined based on sizes of receive (Rx) areas corresponding to a plurality of data Tx beams transmitted in coverage of the BS; and
transmitting at least one RS Tx beam to related Rx areas using the determined beamforming information,
wherein at least one of the Tx period and the beam width of the RS Tx beam is determined separately from the at least one of the Tx period and the beam width of a data Tx beam which is transmitted to an Rx area where the RS TX beam is transmitted.

2. The method of claim 1 , wherein the sizes of the Rx areas increase in proportion to a distance from the BS to the Rx areas.

3. The method of claim 1 , wherein the beamforming info′ nation further includes at least one of a Tx direction and a Tx time of the RS Tx beam.

4. The method of claim 1 , wherein the beam width of the RS Tx beam is determined to be inversely proportional to the size of the Rx area.

5. The method of claim 1 , wherein the Tx period of the RS Tx beam is determined to be proportional to the size of the Rx area.

6. The method of claim 1 , wherein the beam width of the RS Tx beam is equal to or wider than a beam width of the data Tx beam for Downlink (DL) data transmission.

7. The method of claim 1 , wherein a number of RS Tx beams is determined to be equal to or less than a number of available DL Tx beams in coverage of the BS.

8. The method of claim 1 , wherein the RS is transmitted in an RS area that is defined in a frame transmitted by the BS.

9. The method of claim 1 , further comprising providing the determined beamforming information to the MS located in the coverage of the BS.

10. The method of claim 1 , wherein the transmitting comprises transmitting two or more RS Tx beams using the same time-frequency resources.

11. The method of claim 10 , wherein the two or more RS Tx beams transmitted using the same time-frequency resources are each distinguished by at least one of a code, a sequence and a space used during transmission of the two or more RS Tx beams.

12. The method of claim 1 , further comprising:
receiving reception performance information for the RS Tx beam from the MS that has received the RS Tx beam; and
estimating reception performance of the data Tx beam using the received reception performance information.

13. The method of claim 12 , wherein the reception performance of the data Tx beam is estimated using interpolation.

14. The method of claim 1 , further comprising receiving information about reception performance of the data Tx beam from the MS that has received the RS Tx beam, the information estimated based on reception performance of the RS Tx beam.

15. A method for receiving a reference signal (RS) from a base station (BS) by a mobile station (MS) in a mobile communication system using beamforming, the method comprising:
acquiring beamforming information for transmission of a RS transmit (Tx) beam which is used for identifying an optimal data Tx beam by the MS, wherein the beamforming information includes at least one of a Tx period and a beam width of the RS Tx beam which is determined based on sizes of receive (Rx) areas corresponding to a plurality of data Tx beams transmitted in coverage of the BS; and
receiving at least one RS Tx beam including the RS using the acquired beamforming information,
wherein at least one of the Tx period and the beam width of the RS Tx beam is determined separately from the at least one of the Tx period and the beam width of a data Tx beam which is transmitted to an Rx area where the RS Tx beam is transmitted.

16. The method of claim 15 , wherein the sizes of the Rx areas increase in proportion to a distance from the BS to the Rx areas.

17. The method of claim 15 , wherein the beamforming info nation further includes at least one of a Tx direction and a Tx time of the RS Tx beam.

18. The method of claim 15 , wherein the beam width of the RS Tx beam is determined to be inversely proportional to the size of the Rx area.

19. The method of claim 15 , wherein the Tx period of the RS Tx beam is determined to be proportional to the size of the Rx area.

20. The method of claim 15 , wherein the beam width of the RS Tx beam is equal to or wider than a beam width of the data Tx beam for downlink (DL) data transmission.

21. The method of claim 15 , wherein a number of RS Tx beams is determined to be equal to or less than a number of available DL Tx beams in the coverage of the BS.

22. The method of claim 15 , wherein the RS is received in an RS area that is defined in a frame transmitted by the BS.

23. The method of claim 15 , further comprising receiving the at least one RS Tx beam, and selecting the data Tx beam having highest reception performance based on signal strength of each RS Tx beam.

24. The method of claim 15 , wherein the receiving comprises receiving two or more RS Tx beams transmitted using the same time-frequency resources.

25. The method of claim 24 , wherein the two or more RS Tx beams transmitted using the same time-frequency resources are each distinguished by at least one of a code, a sequence and a space used during transmission of the two or more RS Tx beams.

26. The method of claim 15 , further comprising:
measuring reception performance of the RS Tx beam; and
transmitting feedback information including the measured reception performance to the BS.

27. The method of claim 15 , further comprising:
measuring reception performance of the RS Tx beam;
estimating reception performance of the data TX beam using the measured reception performance; and
transmitting feedback information including the estimated reception performance of the data TX beam, to the BS.

28. The method of claim 27 , wherein the reception performance of the data Tx beam is estimated using interpolation.

29. A base station (BS) for transmitting a reference signal (RS) in a mobile communication system using beamforming, the BS comprising:
a transmitter configured to transmit a RS transmit (Tx) beam including the RS and a data Tx beam including data corresponding to the reference signal; and
a controller configured to:
determine beamforming information for transmission of the RS Tx beam which is used for identifying an optimal data Tx beam by a mobile station (MS), wherein the beamforming information includes at least one of a Tx period and a beam width of the RS Tx beam which is determined based on sizes of receive (Rx) areas corresponding to a plurality of data Tx beams transmitted in coverage of the BS, and
control the transmitter to transmit at least one RS Tx beam to related Rx areas using the determined beamforming information,

wherein at least one of the Tx period and the beam width of the RS Tx beam is determined separately from the at least one of the Tx period and the beam width of the data Tx beam which is transmitted to an Rx area where the RS Tx beam is transmitted.

30. The BS of claim 29 , wherein the sizes of the R

Assignees

• Samsung Electronics Co Ltd
• Samsung Electronics Co Ltd

Inventors

• Jung Jung-Soo

Classifications

• H04B7/26 Primary

  at least one of which is mobile · CPC title

• H04W56/00 Primary

  Synchronisation arrangements · CPC title

• H04B7/02 Primary

  Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas (RAKE receivers H04B1/7115) · CPC title