# US 10,484,156 B2 · Search space associated with physical downlink control channel based on channel quality indicators > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,484,156 B2 - Document ID: US10484156B2 - Status: Granted - Kind: B2 - Application number: 15/712,093 - Filed: 2017-09-21 - Published: 2018-05-17 - Granted: 2019-11-19 - Earliest claimed: 2016-11-16 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Chong Li; Junyi Li; Hao Xu - Web page: https://patentgrep.com/patent/US10484156B2 ## CPC - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 5/0082: {at predetermined intervals} - H04L 5/0085: {when channel conditions change} - H04L 5/0094: {Indication of how sub-channels of the path are allocated} - H04L 5/06: the signals being represented by different frequencies (combined with time-division multiplexing H04L5/26) - H04W 74/0858: {collision detection} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04W 84/042: {Public Land Mobile systems, e.g. cellular systems} - 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 first apparatus may send, to a base station, a set of channel quality indicators associated with a set of channels. The first apparatus may monitor sets of control channel elements in a search space based on the set of channel quality indicators sent to the base station. A second apparatus may receive, from a first user equipment, a set of channel quality indicators associated with a set of channels. The second apparatus may send, based on the set of channel quality indicators received from the first user equipment, control information on a physical downlink control channel associated with the first user equipment in a search space specific to the first user equipment. ## Claims ### Claim 1 A method of wireless communication for a base station, the method comprising: communicating with a first user equipment (UE) on a plurality of channels; receiving, from the first UE, a set of channel quality indicators (CQIs) associated with a set of channels that is a subset of the plurality of channels, the set of channels being based on channel qualities associated with the plurality of channels; determining, based on the received set of CQIs, a first set of control channel elements (CCEs) for a UE-specific search space specific to the first UE for receiving a physical downlink control channel (PDCCH)in at least one symbol allocated for control information; and sending, based on the determined first set of CCEs, downlink control information on the PDCCH in the UE-specific search space specific to the first UE. ### Claim 2 (depends on 1) The method of claim 1, further comprising: sending at least a portion of the downlink control information on the PDCCH in a common search space. ### Claim 3 (depends on 2) The method of claim 2, further comprising: detecting a collision between the first set of CCEs associated with the first UE and a second set of CCEs associated with a second UE, wherein downlink control information associated with the second UE is sent in the common search space based on the detected collision. ### Claim 4 (depends on 2) The method of claim 2, further comprising: decoding each CQI of the received set of CQIs; and detecting a decoding failure associated with at least one CQI of the received set of CQIs, wherein the downlink control information carried on the PDCCH is sent in the common search space based on the detected decoding failure. ### Claim 5 (depends on 1) The method of claim 1, wherein the first set of CCEs is determined based on a plurality of received sets of CQIs, each set of CQIs associated with a respective subframe. ### Claim 6 (depends on 1) The method of claim 1, further comprising: sending, to the first UE via radio resource control (RRC) signaling, information indicating at least one of the first set of CCEs associated with the UE-specific search space specific to the first UE or a second set of CCEs associated with a common search space, wherein the downlink control information carried on the PDCCH is carried on the at least one of the first set of CCEs or the second set of CCEs. ### Claim 7 (depends on 1) The method of claim 1, further comprising: receiving, from the first UE, a second set of CQIs associated with a second set of channels; determining, based on the second set of CQIs, a second set of CCEs for second downlink control information carried on the PDCCH; and sending, based on the second set of CCEs, the second downlink control information carried on the PDCCH. ### Claim 8 (depends on 7) The method of claim 7, wherein the first set of CCEs are included in a first subframe and the second set of CCEs are included in a second subframe, the first set of CCEs included in the first subframe being in different locations than the second set of CCEs included in the second subframe. ### Claim 9 An apparatus for wireless communication, the apparatus comprising: means for communicating with a first user equipment (UE) on a plurality of channels: means for receiving, from the first UE, a set of channel quality indicators (CQIs) associated with a set of channels that is a subset of the plurality of channels, the set of channels being based on channel qualities associated with the plurality of channels; means for determining, based on the received set of CQIs, a first set of control channel elements (CCEs) for a UE-specific search space specific to the first UE for receiving a physical downlink control channel (PDCCH) in at least one symbol allocated for control information; and means for sending, based on the determined first set of CCEs, downlink control information on the PDCCH in the UE-specific search space specific to the first UE. ### Claim 10 (depends on 9) The apparatus of claim 9, further comprising: means for sending at least a portion of the downlink control information on the PDCCH in a common search space. ### Claim 11 (depends on 10) The apparatus of claim 10, further comprising: means for detecting a collision between the first set of CCEs associated with the first UE and a second set of CCEs associated with a second UE, wherein downlink control information associated with the second UE is sent in the common search space based on the detected collision. ### Claim 12 (depends on 10) The apparatus of claim 10, further comprising: means for decoding each CQI of the received set of CQIs; and means for detecting a decoding failure associated with at least one CQI of the received set of CQIs, wherein the downlink control information carried on the PDCCH is sent in the common search space based on the detected decoding failure. ### Claim 13 (depends on 9) The apparatus of claim 9, wherein the first set of CCEs is determined based on a plurality of received sets of CQIs, each set of CQIs associated with a respective subframe. ### Claim 14 (depends on 9) The apparatus of claim 9, further comprising: means for sending, to the first UE via radio resource control (RRC) signaling, information indicating at least one of the first set of CCEs associated with the UE-specific search space specific to the first UE or a second set of CCEs associated with a common search space, wherein the downlink control information carried on the PDCCH is carried on the at least one of the first set of CCEs or the second set of CCEs. ### Claim 15 (depends on 9) The apparatus of claim 9, further comprising: means for receiving, from the first UE, a second set of CQIs associated with a second set of channels; means for determining, based on the second set of CQIs, a second set of CCEs for second downlink control information carried on the PDCCH; and means for sending, based on the second set of CCEs, the second downlink control information carried on the PDCCH. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the first set of CCEs are included in a first subframe and the second set of CCEs are included in a second subframe, the first set of CCEs included in the first subframe being in different locations than the second set of CCEs included in the second subframe. ### Claim 17 An apparatus for wireless communication, the apparatus comprising: a memory; and at least one processor coupled to the memory and configured to: communicate with a first user equipment (UE) on a plurality of channels; receive, from the first UE, a set of channel quality indicators (CQIs) associated with a set of channels that is a subset of the plurality of channels, the set of channels being based on channel qualities associated with the plurality of channels; determine, based on the received set of CQIs, a first set of control channel elements (CCEs) for a UE-specific search space specific to the first UE for receiving a physical downlink control channel (PDCCH) in at least one symbol allocated for control information; and send, based on the determined first set of CCEs, downlink control information on the PDCCH in the UE-specific search space specific to the first UE. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: send at least a portion of the downlink control information on the PDCCH in a common search space. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the at least one processor is further configured to: detect a collision between the first set of CCEs associated with the first UE and a second set of CCEs associated with a second UE, wherein downlink control information associated with the second UE is sent in the common search space based on the detected collision. ### Claim 20 (depends on 18) The apparatus of claim 18, wherein the at least one processor is further configured to: decode each CQI of the received set of CQIs; and detect a decoding failure associated with at least one CQI of the received set of CQIs, wherein the downlink control information carried on the PDCCH is sent in the common search space based on the detected decoding failure. ### Claim 21 (depends on 17) The apparatus of claim 17, wherein the first set of CCEs is determined based on a plurality of received sets of CQIs, each set of CQIs associated with a respective subframe. ### Claim 22 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: send, to the first UE via radio resource control (RRC) signaling, information indicating at least one of the first set of CCEs associated with the UE-specific search space specific to the first UE or a second set of CCEs associated with a common search space, wherein the downlink control information carried on the PDCCH is carried on the at least one of the first set of CCEs or the second set of CCEs. ### Claim 23 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: receive, from the first UE, a second set of CQIs associated with a second set of channels; determine, based on the second set of CQIs, a second set of CCEs for second downlink control information carried on the PDCCH; and send, based on the second set of CCEs, the second downlink control information carried on the PDCCH. ### Claim 24 (depends on 23) The apparatus of claim 23, wherein the first set of CCEs are included in a first subframe and the second set of CCEs are included in a second subframe, the first set of CCEs included in the first subframe being in different locations than the second set of CCEs included in the second subframe. ### Claim 25 A non-transitory computer-readable medium storing computer-executable code for wireless communication by a base station, the code comprising instructions executable by a processor to: communicate with a first user equipment (UE) on a plurality of channels; receive, from the first UE, a set of channel quality indicators (CQIs) associated with a set of channels that is a subset of the plurality of channels, the set of channels being based on channel qualities associated with the plurality of channels; determine, based on the received set of CQIs, a first set of control channel elements (CCEs) for a UE-specific search space specific to the first UE for receiving a physical downlink control channel (PDCCH) in at least one symbol allocated for control information; and send, based on the determined first set of CCEs, downlink control information on PDCCH ire the UE-specific search space specific to the first UE. ### Claim 26 (depends on 25) The non-transitory computer-readable medium of claim 25, wherein the instructions are further executable by the processor to: send at least a portion of the downlink control information on the PDCCH in a common search space. ### Claim 27 (depends on 26) The non-transitory computer-readable medium of claim 26, wherein the instructions are further executable by the processor to: detect a collision between the first set of CCEs associated with the first UE and a second set of CCEs associated with a second UE, wherein downlink control information associated with the second UE is sent in the common search space based on the detected collision. ### Claim 28 (depends on 26) The non-transitory computer-readable medium of claim 26, wherein the instructions are further executable by the processor to: decode each CQI of the received set of CQIs; and detect a decoding failure associated with at least one CQI of the received set of CQIs, wherein the downlink control information carried on the PDCCH is sent in the common search space based on the detected decoding failure. ### Claim 29 (depends on 25) The non-transitory computer-readable medium of claim 25, wherein the first set of CCEs is determined based on a plurality of received sets of CQIs, each set of CQIs associated with a respective subframe. ### Claim 30 (depends on 25) The non-transitory computer-readable medium of claim 25, wherein the instructions are further executable by the processor to: send, to the first UE via radio resource control (RRC) signaling, information indicating at least one of the first set of CCEs associated with the UE-specific search space specific to the first UE or a second set of CCEs associated with a common search space, wherein the downlink control information carried on the PDCCH is carried on the at least one of the first set of CCEs or the second set of CCEs.