# US 9,438,403 B2 · Method and apparatus for transmitting a reference signal in a wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,438,403 B2 - Document ID: US9438403B2 - Status: Granted - Kind: B2 - Application number: 14/728,770 - Filed: 2015-06-02 - Published: 2015-09-17 - Granted: 2016-09-06 - Earliest claimed: 2010-05-04 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Min Gyu Kim; Suck Chel Yang; Joon Kui Ahn; Dong Youn Seo - Web page: https://patentgrep.com/patent/US9438403B2 ## CPC - H04L 27/2613: {Structure of the reference signals} - H04L 1/1812: Hybrid protocols; Hybrid automatic repeat request [HARQ] - H04L 1/1861: {Physical mapping arrangements (for ACK signaling see also H04L5/0053)} - 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 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)} - H04L 27/26: Systems using multi-frequency codes (H04L27/32 takes precedence) - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04L 5/0057: {Physical resource allocation for CQI} - 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) ## Abstract A method of transmitting a reference signal in a wireless communication system; and a user equipment therefore are described. The method according to one embodiment includes selecting one or more values among a set {0, 3, 6, 8, 10}; cyclically shifting a base sequence based on the one or more values selected from the set {0, 3, 6, 8, 10}; and transmitting the reference signal based on the cyclically shifted base sequence to a base station. The reference signal is transmitted on a first orthogonal frequency division multiplexing (OFDM) symbol and a second OFDM symbol. The first OFDM symbol is a second OFDM symbol among 7 OFDM symbols in one slot. The second OFDM symbol is a sixth OFDM symbol among the 7 OFDM symbols in the slot. ## Claims ### Claim 1 A method of transmitting a reference signal in a wireless communication system, the method comprising: selecting one or more values among a set {10, 3, 6, 8, 10}; cyclically shifting a base sequence based on the one or more values selected from the set {10, 3, 6, 8, 10}; and transmitting the reference signal based on the cyclically shifted base sequence to a base station, wherein the reference signal is transmitted on a first orthogonal frequency division multiplexing (OFDM) symbol and a second OFDM symbol, wherein the first OFDM symbol is a second OFDM symbol among 7 OFDM symbols in one slot, and wherein the second OFDM symbol is a sixth OFDM symbol among the 7 OFDM symbols in the slot. ### Claim 2 (depends on 1) The method of claim 1, further comprising: generating the base sequence for the reference signal. ### Claim 3 (depends on 1) The method of claim 1, further comprising: receiving, from the base station, a resource configuration including information regarding a plurality of resource candidates. ### Claim 4 (depends on 3) The method of claim 3, further comprising: receiving, from the base station, information indicating a resource index among the plurality of resource candidates; and determining a cyclic shift index according to the resource index. ### Claim 5 (depends on 4) The method of claim 4, wherein the reference signal is used to demodulate a hybrid automatic repeat request (HARQ) positive-acknowledgement (ACK)/negative-acknowledgement (NACK) signal. ### Claim 6 (depends on 5) The method of claim 5, wherein the HARQ ACK/NACK signal is spread to an orthogonal sequence, and wherein an orthogonal sequence index for identifying the orthogonal sequence is determined on the basis of the resource index. ### Claim 7 A user equipment for transmitting a reference signal in a wireless communication system, the user equipment comprising: a transceiver configured to transmit and receive a radio signal; and a processor operatively coupled to the transceiver and configured to: select one or more values among a set {0, 3, 6, 8, 10}, cyclically shift a base sequence based on the one or more values selected from the set {0, 3, 6, 8, 10}, and transmit the reference signal based on the cyclically shifted base sequence to a base station, wherein the reference signal is transmitted on a first orthogonal frequency division multiplexing (OFDM) symbol and a second OFDM symbol, wherein the first OFDM symbol is a second OFDM symbol among 7 OFDM symbols in one slot, and wherein the second OFDM symbol is a sixth OFDM symbol among the 7 OFDM symbols in the slot. ### Claim 8 (depends on 7) The user equipment of claim 7, wherein the processor is further configured to generate the base sequence for the reference signal. ### Claim 9 (depends on 7) The user equipment of claim 7, wherein the processor is further configured to receive, from the base station, a resource configuration including information regarding a plurality of resource candidates. ### Claim 10 (depends on 7) The user equipment of claim 7, wherein the processor is further configured to: receive, from the base station, information indicating a resource index among the plurality of resource candidates, and determine a cyclic shift index according to the resource index. ### Claim 11 (depends on 10) The user equipment of claim 10, wherein the reference signal is used to demodulate a hybrid automatic repeat request (HARQ) positive-acknowledgement (ACK)/negative-acknowledgement (NACK) signal. ### Claim 12 (depends on 11) The user equipment of claim 11, wherein the HARQ ACK/NACK signal is spread to an orthogonal sequence, and wherein an orthogonal sequence index for identifying the orthogonal sequence is determined on the basis of the resource index.