# US 2019/0246366 A1 · Channel Usage Indication and Synchronization for LTE Operation in Unlicensed Bands > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0246366 A1 - Document ID: US20190246366A1 - Status: Published application - Kind: A1 - Application number: 16/387,040 - Filed: 2019-04-17 - Published: 2019-08-08 - Earliest claimed: 2014-09-24 - Assignees: InterDigital Patent Holdings, Inc. - Applicants: InterDigitial Patent Holdings, Inc. - Inventors: Pouriya Sadeghi; Janet A. Stern-Berkowitz; Moon-il Lee; J. Patrick Tooher; Marian Rudolf - Web page: https://patentgrep.com/patent/US20190246366A1 ## CPC - H04W 56/001: {Synchronization between nodes} - 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 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04W 56/00: Synchronisation arrangements - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W 76/27: Transitions between radio resource control [RRC] states - 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 Systems, methods, and instrumentalities are disclosed for LTE operation in an unlicensed spectrum (LTE-U). A wireless transmit/receive unit (WTRU) may establish a connection with a first cell on a licensed frequency band. The WTRU may receive a first downlink transmission from a second cell operating on an unlicensed frequency band. The WTRU may determine that a synchronization signal transmission from a third cell operating on the unlicensed frequency band is transmitted using one or more resource elements. The WTRU may perform frequency and/or timing estimation based on the synchronization signal transmission. The WTRU may perform rate matching around the one or more resource elements that correspond to the synchronization signal transmission. The WTRU may perform rate matching around the one or more resource elements by de-mapping symbols of the downlink transmission. ## Claims ### Claim at position 1 1-34. (canceled) ### Claim 35 A wireless transmit/receive unit (WTRU) comprising: a processor configured to: receive downlink control information (DCI) for a physical downlink shared channel (PDSCH) transmission, the DCI indicating a rate matching configuration for the PDSCH transmission; determine, based on the DCI, a total number of resource elements used for the PDSCH transmission; determine a transport block size (TBS) for the PDSCH transmission based on the total number of resource elements allocated for the PDSCH transmission; and receive the PDSCH transmission comprising a transport block with the determined TBS in accordance with the rate matching configuration indicated in the DCI. ### Claim 36 (depends on 35) The WTRU of claim 35, wherein the rate matching configuration indicates one or more resource elements that are skipped during de-mapping. ### Claim 37 (depends on 35) The WTRU of claim 35, wherein the processor is further configured to receive a synchronization signal, and wherein the synchronization signal comprises at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel (PBCH), a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), or a demodulation reference signal (DMRS). ### Claim 38 (depends on 35) The WTRU of claim 35, wherein the rate matching configuration indicates one or more time and/or frequency resources to be rate matched around when receiving the PDSCH transmission. ### Claim 39 (depends on 35) The WTRU of claim 35, wherein the processor is further configured to perform frequency or timing estimation based on a synchronization signal transmission. ### Claim 40 (depends on 35) The WTRU of claim 35, wherein the rate matching configuration is indicated by a rate matching indicator that identifies the one or more resource elements that are rate matched around when receiving the PDSCH transmission. ### Claim 41 (depends on 35) The WTRU of claim 35, wherein the rate matching configuration is a first rate matching configuration, and wherein the processor is further configured to receive a semi-static configuration corresponding to a plurality of rate matching configurations and the DCI indicates to apply the first rate matching configuration of the plurality of rate matching configurations for the PDSCH transmission. ### Claim 42 (depends on 35) The WTRU of claim 35, wherein the processor is configured to determine the one or more resources that are rate matched around based on the rate matching configuration, and wherein PDSCH data for the WTRU is not mapped to the one or more resource that are rate matched around. ### Claim 43 A method comprising: receiving downlink control information (DCI) for a physical downlink shared channel (PDSCH) transmission, the DCI indicating a rate matching configuration for the PDSCH transmission; determining, based on the DCI, a total number of resource elements used for the PDSCH transmission; determining a transport block size (TBS) for the PDSCH transmission based on the total number of resource elements allocated for the PDSCH transmission; and receiving the PDSCH transmission comprising a transport block with the determined TBS in accordance with the rate matching configuration indicated in the DCI. ### Claim 44 A wireless transmit/receive unit (WTRU) comprising: a processor configured to: receive a power offset indication that indicates a power offset between a synchronization signal transmission and a reference signal transmission; determine, based on the received power offset indication, a reference signal transmission power level; and receive the reference signal transmission. ### Claim 45 (depends on 44) The WTRU of claim 44, wherein the power offset indication is received via higher layer signaling. ### Claim 46 (depends on 44) The WTRU of claim 44, wherein the power offset indication is received in a radio resource control (RRC) message. ### Claim 47 (depends on 44) The WTRU of claim 44, wherein the reference signal transmission comprises a channel state information reference signal (CSI-RS). ### Claim 48 (depends on 44) The WTRU of claim 44, wherein the processor is further configured to determine a synchronization signal transmission power level. ### Claim 49 (depends on 48) The WTRU of claim 48, wherein the processor is further configured to measure the synchronization signal transmission to determine the synchronization signal transmission power level. ### Claim 50 (depends on 48) The WTRU of claim 48, wherein the reference signal transmission power level is determined using the power offset and the synchronization signal transmission power level. ### Claim 51 (depends on 44) The WTRU of claim 44, wherein the processor is further configured to determine the power offset based on the power offset indication. ### Claim 52 (depends on 44) The WTRU of claim 44, wherein the processor is configured to perform frequency or timing estimation based on the synchronization signal transmission. ### Claim 53 (depends on 44) The WTRU of claim 44, wherein the synchronization signal transmission comprises a primary synchronization signal (PSS) and a secondary synchronization signal (SSS).