# US 2018/0324654 A1 · Neighbor cell measurement and reselection for narrowband operation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0324654 A1 - Document ID: US20180324654A1 - Status: Published application - Kind: A1 - Application number: 15/968,543 - Filed: 2018-05-01 - Published: 2018-11-08 - Earliest claimed: 2017-05-04 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Amith CHINCHOLI; Chun-Hao HSU; Gurdeep SINGH - Web page: https://patentgrep.com/patent/US20180324654A1 ## CPC - H04W 36/0061: {of neighbour cell information} - H04W 48/16: Discovering, processing access restriction or access information - H04W 36/0085: {Hand-off measurements} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Aspects of the present disclosure provide techniques that may be utilized by a UE for performing neighbor cell measurement and reselection in narrowband deployment scenarios, such as NB-IoT deployment scenarios. For example, a method for wireless communications by a user equipment (UE), can include determining, while communicating in a serving cell, information regarding one or more transmission deployment mode parameters of at least one neighbor cell, and performing a neighbor cell search with measurement of narrowband reference signals (NRS) based on the one or more transmission deployment mode parameters. ## Claims ### Claim 1 A method for wireless communications by a user equipment (UE), comprising: determining, while communicating in a serving cell, information regarding one or more transmission deployment mode parameters of at least one neighbor cell; and performing a neighbor cell search with measurement of narrowband reference signals (NRS) based on the one or more transmission deployment mode parameters. ### Claim 2 (depends on 1) The method of claim 1, wherein the one or more transmission deployment mode parameters comprise at least one of: a number of transmit antennas used by the neighbor cell, a raster offset of physical resource blocks (PRBs), or information regarding availability of NRS in subframes. ### Claim 3 (depends on 1) The method of claim 1, wherein the determination is based on broadcast signaling of the one or more transmission deployment mode parameters in the serving cell. ### Claim 4 (depends on 1) The method of claim 1, wherein the determining comprises: inferring a number of transmit antennas used by the at least one neighbor cell by evaluating different hypotheses corresponding to different numbers of transmit antennas; and selecting one of the different hypotheses with a higher NRS receive power (NRSRP) than another. ### Claim 5 (depends on 1) The method of claim 1, wherein: the determining comprises determining information regarding availability of NRS in subframes for the at least one neighbor cell is unknown; and the performing the neighbor cell search with measurement comprises assuming a worst case pattern of subframes with a minimum amount of subframes with NRS availability. ### Claim 6 (depends on 1) The method of claim 1, wherein: the determining comprises inferring information regarding availability of NRS in subframes for the at least one neighbor cell by evaluating different hypotheses regarding different subframe bitmaps and selecting one of the different hypotheses with a higher NRS receive power (NRSRP) than another. ### Claim 7 (depends on 6) The method of claim 6, further comprising using the NRSRP of the selected hypothesis for reselection triggering. ### Claim 8 (depends on 6) The method of claim 6, further comprising using the selected hypothesis for decoding a narrowband physical broadcast channel (NPBCH) in the at least one neighbor cell. ### Claim 9 (depends on 1) The method of claim 1, wherein the determining comprises inferring information about a raster offset by: performing an initial acquisition in the at last one neighbor cell to determine a total frequency offset; and applying the total frequency offset before refining frame and symbol timing, residual frequency error, and determining a physical cell ID (PCID) of the at least one neighbor cell. ### Claim 10 (depends on 1) The method of claim 1, wherein the determining comprises inferring information about a raster offset by: evaluating a plurality of different hypotheses for different frequency errors to find frame and symbol timing; and using one of the plurality of different hypotheses, selected based on the evaluation, to detect narrowband primary synchronization signals (NPSS) and narrowband secondary synchronization signals. ### Claim 11 An apparatus for wireless communications by a user equipment (UE), comprising: means for determining, while communicating in a serving cell, information regarding one or more transmission deployment mode parameters of at least one neighbor cell; and means for performing a neighbor cell search with measurement of narrowband reference signals (NRS) based on the one or more transmission deployment mode parameters. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the one or more transmission deployment mode parameters comprise at least one of: a number of transmit antennas used by the neighbor cell, a raster offset of physical resource blocks (PRBs), or information regarding availability of NRS in subframes. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the determination is based on broadcast signaling of the one or more transmission deployment mode parameters in the serving cell. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the means for determining comprises: means for inferring a number of transmit antennas used by the at least one neighbor cell by evaluating different hypotheses corresponding to different numbers of transmit antennas; and means for selecting one of the different hypotheses with a higher NRS receive power (NRSRP) than another. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein: the means for determining comprises means for determining information regarding availability of NRS in subframes for the at least one neighbor cell is unknown; and the means for performing the neighbor cell search with measurement comprises means for assuming a worst case pattern of subframes with a minimum amount of subframes with NRS availability. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein: the means for determining comprises means for inferring information regarding availability of NRS in subframes for the at least one neighbor cell by evaluating different hypotheses regarding different subframe bitmaps and selecting one of the different hypotheses with a higher NRS receive power (NRSRP) than another. ### Claim 17 (depends on 16) The apparatus of claim 16, further comprising means for using the NRSRP of the selected hypothesis for reselection triggering. ### Claim 18 (depends on 16) The apparatus of claim 16, further comprising means for using the selected hypothesis for decoding a narrowband physical broadcast channel (NPBCH) in the at least one neighbor cell. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein the means for determining comprises means for inferring information about a raster offset that includes: means for performing an initial acquisition in the at last one neighbor cell to determine a total frequency offset; and means for applying the total frequency offset before refining frame and symbol timing, residual frequency error, and means for determining a physical cell ID (PCID) of the at least one neighbor cell. ### Claim 20 (depends on 11) The apparatus of claim 11, wherein the means for determining comprises means for inferring information about a raster offset that includes: means for evaluating a plurality of different hypotheses for different frequency errors to find frame and symbol timing; and means for using one of the plurality of different hypotheses, selected based on the evaluation, to detect narrowband primary synchronization signals (NPSS) and narrowband secondary synchronization signals. ### Claim 21 An apparatus for wireless communication by a user equipment (UE), comprising: at least one processor configured to: determine, while communicating in a serving cell, information regarding one or more transmission deployment mode parameters of at least one neighbor cell; and perform a neighbor cell search with measurement of narrowband reference signals (NRS) based on the one or more transmission deployment mode parameters; and a memory coupled to the at least one processor. ### Claim 22 A non-transitory computer readable medium for wireless communication by a user equipment (UE) having instructions stored thereon for: determining, while communicating in a serving cell, information regarding one or more transmission deployment mode parameters of at least one neighbor cell; and performing a neighbor cell search with measurement of narrowband reference signals (NRS) based on the one or more transmission deployment mode parameters.