Wireless communication system, method for transmitting information of user equipment, method for receiving information of base station, and user equipment and base station thereof

• US 10,097,251 B2
• Filed: 06/10/2016
• Issued: 10/09/2018
• Est. Priority Date: 06/15/2015
• Status: Active Grant

• Current Assignee: KT Corporation
• Original Assignee: KT Corporation
• Inventors: Lee, Hyo Jin, Kim, Young Seok, Kwak, Do-Young
• Primary Examiner(s): BUTT, WALLI Z
• Application Number:
  US15/178,735
• Publication Number:
  US 20160365957A1
• Time in Patent Office: 851 Days
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal

Abstract

The present disclosure provides a wireless communication system including a plurality of remote units, and a digital unit configured to connect one output port to at least one of i) one remote unit having a maximum antenna number of antennas among the plurality of remote units and ii) two or more remote units each having antennas smaller than the maximum antenna number among the plurality of remote units.

Claims

1. A wireless communication system comprising:

a plurality of remote antenna units distributedly installed in a plurality of cell areas and configured to communicate with at least one user equipment, wherein each of the plurality of remote antenna units includes at least one antenna; and

a digital controller configured to include a plurality of output ports and to provide, though the plurality of output ports, a data service for the plurality of cell areas respectively formed by the plurality of remote antenna units,

wherein i) one remote antenna unit having a maximum antenna number of antennas among the plurality of remote antenna units is connected to one of the plurality of output ports of the digital controller and ii) two or more remote antenna units each having antennas fewer than the maximum antenna number among the plurality of remote antenna units are connected to share another of the plurality of output ports of the digital controller, and

wherein the digital controller i) receives, from a specific User Equipment (UE), antenna port information for identifying an antenna port supporting a cell area where the specific UE is located, among the plurality of cell areas, ii) identifies the cell area where the specific UE is located through the received antenna port information, and iii) performs a separate scheduling operation for the specific UE located in the identified cell area.

2. The wireless communication system of claim 1, further comprising:

a signal distributor connected to the digital controller and at least one of the plurality of remote antenna units and configured to distribute a signal transmitted from the digital controller to one of the connected remote antenna units.

3. The wireless communication system of claim 1, wherein at least one of the plurality of remote antenna units is configured to have at least two distributedly installed antennas, and

the digital controller is configured to support a data service for at least two cell areas respectively formed by the at least two distributedly installed antennas of the remote antenna unit.

16. The wireless communication system of claim 1, wherein the antenna port information is transmitted by being included in a port indicator.

4. A method of transmitting information of a User Equipment (UE), the method comprising:

receiving a Channel Status Information Reference Signal (CSI-RS) from a base station, wherein the base station includes a plurality of remote antenna units distributedly installed in a plurality of cell areas;

generating antenna port information which identifies an antenna port supporting a cell area where the UE locates, through the received CSI-RS; and

transmitting the antenna port information to the base station, wherein the antenna port information is used, at the base station, to identify the cell area where the UE is located, and

wherein the digital controller i) receives, from a specific User Equipment (UE), antenna port information for identifying an antenna port supporting a cell area where the specific UE is located among the plurality of cell areas, ii) identifies the cell area where the specific UE is located through the received antenna port information, and iii) performs a separate scheduling operation for the specific UE located in the identified cell area.

5. The method of claim 4, wherein the antenna port information is transmitted by being included in at least one of channel state information and port information.

6. The method of claim 5, wherein the channel state information is a Precoding Matrix Index (PMI), and the port information is a port indicator.

7. The method of claim 4, wherein the generating comprises generating (log₂N+1) bit of antenna port information for identifying all possible combinations of 1, 2, or N antenna ports when a number of the antenna ports is N.

8. The method of claim 4, wherein the generating comprises generating a specific bit of antenna port information for identifying some of all possible combinations of 1, 2, or N antenna ports when the number of the antenna ports is N.

9. The method of claim 5, wherein, when the antenna port information is included in the port information, the port information is transmitted at a timing that is equal to that of the channel state information or transmitted in a period corresponding to an integer times of a rank index which is one of the channel state information.

10. A method of receiving information of a base station, the method comprising:

configuring the base station as including i) a plurality of remote antenna units distributedly installed in a plurality of cell areas and further configured to communicate with at least one user equipment and ii) a digital controller configured to include a plurality of output ports and to provide, though the plurality of output ports, a data service for the plurality of cell areas respectively formed by the plurality of remote antenna units;

transmitting a Channel Status Information Reference Signal (CSI-RS) to a user equipment (UE);

receiving, by the digital controller, from the UE, antenna port information for identifying an antenna port supporting a cell area where the UE is located, wherein the antenna port information is generated by the UE based on the CSI-RS;

identifying, by the digital controller, the cell area where the UE is located through the antenna port information;

performing a separate scheduling operation, by the digital controller, for the UE located in the identified cell area; and

performing, by the digital controller, a data transmission.

11. The method of claim 10, wherein the antenna port information is received by being included in one of channel state information and port information.

12. The method of claim 11, wherein the channel state information is a Precoding Matrix Index (PMI), and the port information is a port indicator.

13. The method of claim 10, wherein the receiving comprises receiving (log₂N+1) bit of antenna port information for identifying all possible combinations of 1, 2 or N antenna ports when the number of the antenna ports is N.

14. The method of claim 10, wherein the receiving comprises receiving a specific bit of antenna port information for identifying some of all possible combinations of 1, 2, or N antenna ports when the number of the antenna ports is N.

15. The method of claim 11, wherein, when the antenna port information is included in the port information, the port information is received at a timing that is equal to that of the channel state information, or received in a period corresponding to an integer times of a rank index, which is one of the channel state information.