# US 10,320,544 B2 · Method and apparatus for transmitting a reference signal in a multi-antenna system

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,320,544 B2
- Document ID: US10320544B2
- Status: Granted
- Kind: B2
- Application number: 15/913,491
- Filed: 2018-03-06
- Published: 2018-07-12
- Granted: 2019-06-11
- Earliest claimed: 2009-09-16
- Assignees: LG Electronics Inc.
- Applicants: LG Electronics Inc.
- Inventors: Min Seok Noh; Hyun Soo Ko; Seung Hee Han; Jae Hoon Chung; Moon Il Lee
- Web page: https://patentgrep.com/patent/US10320544B2

## CPC

- H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)}
- H04L 5/0023: {Time-frequency-space}
- H04L 27/2605: {Symbol extensions, e.g. Zero Tail, Unique Word [UW]}
- H04L 27/2613: {Structure of the reference signals}
- H04L 27/2633: {using partial FFTs}
- H04L 27/2636: {with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]}
- H04L 27/2637: {with direct modulation of individual subcarriers}
- H04W 72/0446: Resources in time domain, e.g. slots or frames
- H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal
- H04B 7/0613: {using simultaneous transmission (H04B7/0686 takes precedence)}
- H04W 88/06: adapted for operation in multiple networks {or having at least two operational modes}, e.g. multi-mode terminals
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04B: TRANSMISSION

## Abstract

A method for transmitting a demodulation reference signal (DM-RS), by a user equipment (UE), in a wireless communication system is discussed. The method includes receiving, by the UE from a base station, a cyclic shift field in downlink control information (DCI), wherein the cyclic shift field indicates first, second, and third cyclic shift values for first, second, and third layers respectively, generating, by the UE, first, second, and third DMRSs for the first, second, and third layers respectively, based on first, second, and third cyclic shifts respectively, wherein the first, second, and third cyclic shifts are determined based on the first, second, and third cyclic shift values respectively, and transmitting, by the UE to the base station, the first, second, and third DMRSs.

## Claims

### Claim 1

A method for transmitting demodulation reference signals (DMRSs), by a user equipment (UE), in a wireless communication system, the method comprising:
receiving, by the UE from a base station, a cyclic shift field in downlink control information (DCI), wherein the cyclic shift field indicates first, second, and third cyclic shift values for first, second, and third layers respectively, by table below:
First cyclic
Second cyclic
Third cyclic
shift value
shift value
shift value
Cyclic shift field
for first layer
for second layer
for third layer
000
0
6
3
001
6
0
9
010
3
9
6
011
4
10
7
100
2
8
5
101
8
2
11
110
10
4
1
111
9
3
0
generating, by the UE, first, second, and third DMRSs for the first, second, and third layers respectively, based on first, second, and third cyclic shifts respectively, wherein the first, second, and third cyclic shifts are determined based on the first, second, and third cyclic shift values respectively; and
transmitting, by the UE to the base station, the first, second, and third DMRSs.

### Claim 2

A user equipment (UE) in a wireless communication system, the UE comprising:
a memory;
a transceiver; and
a processor, operably coupled to the memory and the transceiver, that:
controls the transceiver to receive, from a base station, a cyclic shift field in downlink control information (DCI), wherein the cyclic shift field indicates first, second, and third cyclic shift values for first, second, and third layers respectively, by table below:
First cyclic
Second cyclic
Third cyclic
shift value for
shift value
shift value
Cyclic shift field
first layer
for second layer
for third layer
000
0
6
3
001
6
0
9
010
3
9
6
011
4
10
7
100
2
8
5
101
8
2
11
110
10
4
1
111
9
3
0
generates first, second, and third demodulation reference signals (DMRSs) for the first, second, and third layers respectively, based on first, second, and third cyclic shifts respectively, wherein the first, second, and third cyclic shifts are determined based on the first, second, and third cyclic shift values respectively, and
controls the transceiver to transmit, to the base station, the first, second, and third DMRSs.