Method and apparatus for transmitting reference signal

• US 9,602,258 B2
• Filed: 03/25/2013
• Issued: 03/21/2017
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Bonghoe, Seo, Dongyoun, You, Hyangsun, Ahn, Joonkui
• Primary Examiner(s): Nguyen, Brian D
• Assistant Examiner(s): NGUYEN, TOAN D
• Application Number:
  US14/384,574
• Publication Number:
  US 20150055574A1
• Time in Patent Office: 1,457 Days
• US Class Current: 1/1
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• CPC Class Codes: H04J 11/0073 Acquisition of primary synchronisation channel, e.g. detection of cell-ID within cell-ID group
• CPC Class Codes: H04J 11/0076 Acquisition of secondary synchronisation channel, e.g. detection of cell-ID group
• CPC Class Codes: H04J 2211/005 Long term evolution [LTE]
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

Disclosed are a method and an apparatus for transmitting a reference signal. The method for transmitting the reference signal comprises the step of: transmitting a secondary synchronization signal (SSS) and a primary synchronization signal (PSS) from a subframe including an N (natural number wherein N>1) number of resource blocks (RB) and a plurality of orthogonal frequency division multiplexing (OFDM) symbols; and transmitting from the subframe the reference signal which is generated on the basis of a cell identifier, wherein the reference signal can be transmitted from an M (natural number wherein K<=M<N) number of RBs which includes a K number of RBs in the OFDM symbols that remain after excluding the OFDM symbols from which the SSS and the PSS are transmitted. As a result, demodulation capability of a terminal can be increased.

Claims

1. A method for transmitting a reference signal, the method comprising:

transmitting a secondary synchronization signal (SSS) and a primary synchronization signal (PSS) in a subframe including N resource blocks (RBs) and a plurality of orthogonal frequency division multiplexing (OFDM) symbols; and

transmitting a reference signal created based on a cell identifier in the subframe,

wherein the PSS is transmitted in K contiguous RBs selected from a plurality of RBs in a sixth OFDM symbol of the subframe,

wherein the SSS is transmitted in K contiguous RBs selected from the plurality of RBs in a seventh OFDM symbol of the subframe,

wherein the reference signal is transmitted in M RBs including K RBs in the remaining OFDM symbols except for the sixth OFDM symbol and the seventh OFDM symbol,

wherein N is a natural number greater than 1,

wherein K is a natural number less than N,

wherein M is a natural number greater than or equal to K and less than N,

wherein M is an even number when N is an even number,

wherein M is an odd number when N is an odd number, and

wherein the reference signal is transmitted through an additional frequency bandwidth when a frequency band in which the reference signal is transmitted and a boundary of the RBs in which the reference signal is transmitted do not coincide with each other.

2. The method of claim 1, wherein:

the reference signal is transmitted in K RBs when N and K are both even numbers;

the reference signal is transmitted in K+1 RBs when N is an even number and K is an odd number; and

the K RBs and the K+1 RBs are frequency bands selected based on center RBs among the N RBs.

3. The method of claim 1, wherein:

the reference signal is transmitted in K RBs when N and K are both odd numbers;

the reference signal is transmitted in K+1 RBs when N is an odd number and K is an even number; and

the K RBs and the K+1 RBs are frequency bands selected based on center RBs among the N RBs.

4. A base station for transmitting a reference signal in a wireless communication system, the base station comprising:

a processor configured to transmit a secondary synchronization signal (SSS) and a primary synchronization signal (PSS) in a subframe including N resource blocks (RBs) and a plurality of orthogonal frequency division multiplexing (OFDM) symbols and to transmit a reference signal created based on a cell identifier in the subframe,

wherein the PSS is transmitted in K contiguous RBs selected from a plurality of RBs in a sixth OFDM symbol of the subframe,

wherein the SSS is transmitted in K contiguous RBs selected from the plurality of RBs in a seventh OFDM symbol of the subframe,

wherein the reference signal is transmitted in M RBs including K RBs in the remaining OFDM symbols except for the sixth OFDM symbol and the seventh OFDM symbol,

wherein N is a natural number greater than 1,

wherein K is a natural number less than N,

wherein M is a natural number greater than or equal to K and less than N,

wherein M is an even number when N is an even number,

wherein M is an odd number when N is an odd number, and

wherein the reference signal is transmitted through an additional frequency bandwidth when a frequency band in which the reference signal is transmitted and a boundary of the RBs in which the reference signal is transmitted do not coincide with each other.

5. The base station of claim 4, wherein the processor is further configured to:

transmit the reference signal in the K RBs when N and K are both even numbers; and

transmit the reference signal in K+1 RBs when N is an even number and K is an odd number,

wherein the K RBs and the K+1 RBs are frequency bands selected based on center RBs among the N RBs.

6. The base station of claim 4, wherein the processor is further configured to:

transmit the reference signal in K RBs when N and K are both odd numbers; and

transmit the reference signal in K+1 RBs when N is an odd number and K is an even number,

wherein the K RBs and the K+1 RBs are frequency bands selected based on center RBs among the N RBs.