Technique for transmitting and receiving downlink reference signals

Patent metadata

Field	Value
Publication number	US-2016007328-A1
Application number	US-201514852807-A
Country	US
Kind code	A1
Filing date	Sep 14, 2015
Priority date	Feb 3, 2009
Publication date	Jan 7, 2016
Grant date	—

Abstract

A technique for receiving and transmitting downlink reference signals is disclosed. When transmitting downlink data demodulation reference signals (DMRS) (or reference signals for downlink data demodulation) by using two or more layers, the DMRS of each layer may be multiplexed by using a code division multiplexing method and then transmitted. The DMRS for each of the two or more layers may be used for one user equipment or for two or more user equipments. And, downlink control signals for transmitting and receiving such DMRS may be configured to have the same format regardless of a single-user mode (or SU-MIMO mode) or a multi-user mode (or MU-MIMO mode), thereby being used.

First claim

What is claimed is:

1 . A method of transmitting downlink signals to a user equipment (UE) at a base station (BS) in a multiple input multiple output (MIMO) wireless communication system, the method comprising:
transmitting a downlink control channel to the UE; and transmitting a downlink data channel and a downlink reference signal for the demodulation of a downlink data channel, to the UE, wherein: when the downlink data channel comprises only one transmission layer, the downlink control channel includes information indicating which antenna port is used for transmitting the downlink reference signal among a plurality of antenna ports, and when the downlink data channel comprises two or more transmission layers, the downlink reference signal is transmitted on two or more fixed antenna ports among the plurality of antenna ports.

2 . The method of claim 1 , wherein the downlink data channel and the downlink reference signal are processed according to a same precoding procedure.

3 . The method of claim 1 , wherein:
when the downlink data channel comprises only the one transmission layer, the downlink data channel is transmitted on the indicated antenna port, and when the downlink data channel comprises the two or more transmission layers, the downlink data channel is transmitted on the two or more fixed antenna ports.

4 . A method of receiving downlink signals from a base station (BS) at a user equipment (UE) in a multiple input multiple output (MIMO) wireless communication system, the method comprising:
receiving a downlink control channel from the BS; and receiving a downlink data channel and a downlink reference signal for demodulation of the downlink data channel from the BS, wherein: when the downlink data channel comprises only one transmission layer, the downlink control channel includes information indicating which antenna port is used for receiving the downlink reference signal among a plurality of antenna ports, and when the downlink data channel comprises two or more transmission layers, the downlink reference signal is received on two or more fixed antenna ports among the plurality of antenna ports.

5 . The method of claim 4 , wherein the downlink data channel and the downlink reference signal are processed according to a same precoding procedure by the BS.

6 . The method of claim 4 , wherein:
when the downlink data channel comprises only the one transmission layer, the downlink data channel is received on the indicated antenna port, and when the downlink data channel comprises the two or more transmission layers, the downlink data channel is received on the two or more fixed antenna ports.

7 . A base station (BS) in a multiple input multiple output (MIMO) wireless communication system, the BS comprising:
a processor for generating downlink signals comprising a downlink control channel, a downlink data channel and a downlink reference signal for the demodulation of a downlink data channel; and a transmitter module for transmitting the downlink control channel, the downlink data channel and the downlink reference signal to a user equipment (UE), wherein: when the downlink data channel comprises only one transmission layer, the downlink control channel includes information indicating which antenna port is used for transmitting the downlink reference signal among a plurality of antenna ports, and when the downlink data channel comprises two or more transmission layers, the downlink reference signal is transmitted on two or more fixed antenna ports among the plurality of antenna ports.

8 . The BS of claim 7 , wherein the processor processes the downlink data channel and the downlink reference signal according to a same precoding procedure.

9 . The BS of claim 7 , wherein:
when the downlink data channel comprises only the one transmission layer, the downlink data channel is transmitted on the indicated antenna port, and when the downlink data channel comprises the two or more transmission layers, the downlink data channel is transmitted on the two or more fixed antenna ports.

10 . A user equipment (UE) in a multiple input multiple output (MIMO) wireless communication system, the UE comprising:
a receiver for receiving, from a base station (BS), downlink signals comprising a downlink control channel, a downlink data channel and a downlink reference signal for a demodulation of the downlink data channel; and a processor for processing the downlink signals, wherein: when the downlink data channel comprises only one transmission layer, the downlink control channel includes information indicating which antenna port is used for receiving the downlink reference signal among a plurality of antenna ports, and when the downlink data channel comprises two or more transmission layers, the downlink reference signal is received on two or more fixed antenna ports among the plurality of antenna ports.

11 . The UE of claim 10 , wherein the downlink data channel and the downlink reference signal are processed according to a same precoding procedure by the BS.

12 . The UE of claim 10 , wherein:
when the downlink data channel comprises only the one transmission layer, the downlink data channel is received on the indicated antenna port, and when the downlink data channel comprises the two or more transmission layers, the downlink data channel is received on the two or more fixed antenna ports.

Assignees

• Lg Electronics Inc

Inventors

• Lee Moon Il
• Lee Wook Bong
• Chung Jae Hoon
• Ko Hyun Soo
• Ihm Bin Chul

Classifications

• H04W72/23 Primary

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04L5/0023

  Time-frequency-space · CPC title

• H04L25/03343

  Arrangements at the transmitter end · CPC title

• H04W72/042 Primary

  Electricity · mapped topic

• H04B7/0452

  Multi-user MIMO systems · CPC title