# US 10,375,686 B2 · Method and apparatus for component carrier aggregation in wireless communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,375,686 B2 - Document ID: US10375686B2 - Status: Granted - Kind: B2 - Application number: 15/988,881 - Filed: 2018-05-24 - Published: 2018-09-27 - Granted: 2019-08-06 - Earliest claimed: 2009-01-30 - Assignees: InterDigital Patent Holdings, Inc. - Applicants: Interdigital Patent Holdings, Inc. - Inventors: Kyle Jung-Lin Pan; Jean-Louis Gauvreau; Guodong Zhang; Philip J. Pietraski; Sung-Hyuk Shin - Web page: https://patentgrep.com/patent/US10375686B2 ## CPC - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 5/001: {the frequencies being arranged in component carriers} - H04L 5/0037: {Inter-user or inter-terminal allocation} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 5/0091: {Signalling for the administration of the divided path, e.g. signalling of configuration information} - H04L 27/2656: {Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A wireless transmit/receive unit (WTRU) receives a downlink subframe having multiple component carriers, each component carrier having control information encoded in a physical data control channel (PDCCH). The WTRU performs a blind decoding of control information in a first PDCCH located within a first component carrier to obtain a location of a second PDCCH located within a second component carrier, where the location of the second PDCCH is relative to a location of the first PDCCH as control channel element offset. The WTRU decodes the second PDCCH at the obtained location. ## Claims ### Claim 1 A wireless transmit/receive unit (WTRU) comprising a processor configured to: receive search space restriction information, wherein the search space restriction information comprises an indication of which aggregation levels should be used for decoding physical downlink control channel (PDCCH) candidates in a search space, and the search space restriction information further comprises an indication of which control channel element (CCE) candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level; decode a control channel transmission in accordance with the search space restriction information, the control channel transmission comprising downlink control information for a data transmission; and process the data transmission in accordance with the downlink control information comprised in the control channel transmission. ### Claim 2 (depends on 1) The WTRU as in claim 1, wherein the indication of which CCE candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level indicates that certain CCE candidates can be excluded when performing blind decoding at a given aggregation level. ### Claim 3 (depends on 1) The WTRU of claim 1, wherein the indication of which CCE candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level is provided for each aggregation level configured for the search space. ### Claim 4 (depends on 1) The WTRU of claim 1, wherein the search space is a WTRU-specific search space. ### Claim 5 (depends on 1) The WTRU of claim 1, wherein the search space restriction information is received via radio resource control (RRC) signaling. ### Claim 6 (depends on 1) The WTRU of claim 1, wherein decoding a control channel transmission in accordance with the search space restriction information results in the WTRU attempting to decode a subset of a set of possible CCE candidates for a given aggregation level. ### Claim 7 (depends on 1) The WTRU of claim 1, wherein the search space restriction information is provided per component carrier. ### Claim 8 A method implemented by a wireless transmit/receive unit (WTRU), the method comprising: receiving search space restriction information, wherein the search space restriction information comprises an indication of which aggregation levels should be used for decoding physical downlink control channel (PDCCH) candidates in a search space, and the search space restriction information further comprises an indication of which control channel element (CCE) candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level; decoding a control channel transmission in accordance with the search space restriction information, the control channel transmission comprising downlink control information for a data transmission; and processing the data transmission in accordance with the downlink control information comprised in the control channel transmission. ### Claim 9 (depends on 8) The method as in claim 8, wherein the indication of which CCE candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level indicates that certain CCE candidates can be excluded when performing blind decoding at a given aggregation level. ### Claim 10 (depends on 8) The method of claim 8, wherein the indication of which CCE candidates should be used to attempt to decode a PDCCH candidate at a given aggregation level is provided for each aggregation level configured for the search space. ### Claim 11 (depends on 8) The method of claim 8, wherein the search space is a WTRU-specific search space. ### Claim 12 (depends on 8) The method of claim 8, wherein the search space restriction information is received via radio resource control (RRC) signaling. ### Claim 13 (depends on 8) The method of claim 8, wherein decoding a control channel transmission in accordance with the search space restriction information results in the WTRU attempting to decode a subset of a set of possible CCE candidates for a given aggregation level. ### Claim 14 (depends on 8) The method of claim 8, wherein the search space restriction information is provided per component carrier. ### Claim 15 A network node comprising a processor configured to: send search space restriction information to a wireless transmit/receive unit (WTRU), wherein the search space restriction information comprises an indication of which aggregation levels should be used by the WTRU for decoding physical downlink control channel (PDCCH) candidates in a search space, and the search space restriction information further indicates which control channel element (CCE) candidates should be used by the WTRU to attempt to decode a PDCCH candidate at a given aggregation level; send a control channel transmission in accordance with the search space restriction information, the control channel transmission comprising downlink control information for a data transmission; and process the data transmission in accordance with the downlink control information comprised in the control channel transmission.