# US 11,122,535 B2 · Techniques for locating devices using narrowband positioning reference signals > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,122,535 B2 - Document ID: US11122535B2 - Status: Granted - Kind: B2 - Application number: 15/646,730 - Filed: 2017-07-11 - Published: 2018-01-18 - Granted: 2021-09-14 - Earliest claimed: 2016-07-15 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Renqiu Wang; Wanshi Chen; Hao Xu; Alberto Rico Alvarino; Peter Gaal - Web page: https://patentgrep.com/patent/US11122535B2 ## CPC - H04W 64/00: Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management - H04B 17/318: Received signal strength - 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 4/70: Services for machine-to-machine communication [M2M] or machine type communication [MTC] - H04W 74/004: {in the uplink, i.e. towards network} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Certain aspects of the present disclosure generally relate to DL-based and UL-based positioning reference signal (PRS) techniques that may help facilitate positioning procedures in systems deploying narrowband devices, such as NB-IoT devices. An exemplary method includes determining resources within a narrowband region of a wider system bandwidth for transmitting a positioning reference signal (PRS), transmitting the PRS using the determined resources, and estimating a position of a wireless node based on at least one first measurement of a first reference signal and the PRS transmitted within a narrowband region. ## Claims ### Claim 1 A method for wireless communications, by a base station (BS), comprising: determining resources within a narrowband region of a wider system bandwidth for transmitting a positioning reference signal (PRS); transmitting the PRS using the determined resources; determining, based on a coverage enhancement (CE) level of a wireless node, a positioning accuracy for the wireless node; and estimating a position of the wireless node based on at least one first measurement of a first reference signal, the PRS, and the determined positioning accuracy. ### Claim 2 (depends on 1) The method of claim 1, wherein the at least one first measurement comprises at least one of a measurement of a power of the first reference signal observed by the wireless node or a timing of the first reference signal observed by the wireless node. ### Claim 3 (depends on 1) The method of claim 1, wherein the first reference signal comprises at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a cell-specific reference signal (CRS), or a physical broadcast channel (PBCH) from one or more base stations. ### Claim 4 (depends on 1) The method of claim 1, wherein a configuration of the PRS is based on a virtual cell identifier (VCID) of the BS. ### Claim 5 (depends on 1) The method of claim 1, wherein determining the resources comprises determining a first number of consecutive subframes larger than a second number of consecutive subframes for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 6 (depends on 1) The method of claim 1, wherein determining the resources is based on a first periodicity that is shorter than a second periodicity used for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 7 (depends on 1) The method of claim 1, wherein determining the resources comprises determining a set of time and frequency resources not used for other downlink transmissions. ### Claim 8 (depends on 1) The method of claim 1, wherein determining the resources comprises determining a first set of frequency resources different from a second set of frequency resources used by another BS for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 9 (depends on 1) The method of claim 1, further comprising: transmitting a non-PRS signal to the wireless node; and receiving a second measurement of the non-PRS signal, wherein the estimating the position is further based on the second measurement. ### Claim 10 (depends on 9) The method of claim 9, wherein the second measurement comprises at least one of a measurement of a power of the non-PRS signal as observed by the wireless node or a measurement of a timing of the non-PRS signal as observed by the wireless node. ### Claim 11 (depends on 1) The method of claim 1, further comprising: requesting the wireless node to transmit a physical random access channel (PRACH); and receiving the PRACH, wherein the estimating the position is further based on the PRACH. ### Claim 12 (depends on 1) The method of claim 1, further comprising: receiving at least one sounding reference signal (SRS) from the wireless node, wherein the estimating the position is further based on the SRS. ### Claim 13 (depends on 1) The method of claim 1, wherein transmitting the PRS comprises transmitting the PRS to the wireless node via another wireless node having a known location, and wherein the estimating the position is further based on the known location. ### Claim 14 (depends on 1) The method of claim 1, further comprising: obtaining a second measurement of the PRS from another wireless node having a known location, wherein the estimating the position is further based on the second measurement and the known location. ### Claim 15 An apparatus for wireless communications, comprising: means for determining resources within a narrowband region of a wider system bandwidth for transmitting a positioning reference signal (PRS); means for transmitting the PRS using the determined resources; means for determining, based on a coverage enhancement (CE) level of a wireless node, a positioning accuracy for the wireless node; and means for estimating a position of the wireless node based on at least one first measurement of a first reference signal, the PRS, and the determined positioning accuracy. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the at least one first measurement comprises at least one of a measurement of a power of the first reference signal observed by the wireless node or a timing of the first reference signal observed by the wireless node. ### Claim 17 (depends on 15) The apparatus of claim 15, wherein the first reference signal comprises at least one of a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a cell-specific reference signal (CRS), or a physical broadcast channel (PBCH) from one or more base stations. ### Claim 18 (depends on 15) The apparatus of claim 15, wherein the means for determining the resources comprises means for determining a first number of consecutive subframes larger than a second number of consecutive subframes for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 19 (depends on 15) The apparatus of claim 15, wherein the means for determining the resources comprises means for determining the resources based on a first periodicity that is shorter than a second periodicity used for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 20 (depends on 15) The apparatus of claim 15, wherein the means for determining the resources comprise means for determining a set of time and frequency resources not used for other downlink transmissions. ### Claim 21 (depends on 15) The apparatus of claim 15, wherein a base station (BS) transmits the PRS and the means for determining the resources comprises means for determining a first set of frequency resources different from a second set of frequency resources used by another BS for transmitting one or more other PRS to one or more other wireless nodes. ### Claim 22 (depends on 15) The apparatus of claim 15, further comprising: means for transmitting a non-PRS signal to the wireless node; and means for receiving a second measurement of the non-PRS signal, wherein the means for estimating the position comprises means for estimating the position based on the second measurement. ### Claim 23 (depends on 15) The apparatus of claim 15, further comprising: means for requesting the wireless node to transmit a physical random access channel (PRACH); and means for receiving the PRACH, wherein the means for estimating the position comprises means for estimating the position based on the PRACH. ### Claim 24 (depends on 15) The apparatus of claim 15, further comprising: means for receiving at least one sounding reference signal (SRS) from the wireless node, wherein the means for estimating the position comprises means for estimating the position based on the SRS. ### Claim 25 (depends on 15) The apparatus of claim 15, wherein the PRS is transmitted to the wireless node from a base station via another wireless node having a known location, and wherein the means for estimating the position comprises means for estimating the position based on the known location. ### Claim 26 An apparatus for wireless communications, comprising: a processing system configured to: determine resources within a narrowband region of a wider system bandwidth for transmitting a positioning reference signal (PRS), cause transmission of the PRS using the determined resources, determine, based on a coverage enhancement (CE) level of a wireless node, a positioning accuracy for the wireless node; and estimate a position of the wireless node based on at least one first measurement of a first reference signal, the PRS, and the determined positioning accuracy; and a memory coupled with the processing system. ### Claim 27 A non-transitory computer readable medium for wireless communications storing computer executable code, the code comprising instructions for: determining resources within a narrowband region of a wider system bandwidth for transmitting a positioning reference signal (PRS); transmitting the PRS using the determined resources; determining, based on a coverage enhancement (CE) level of a wireless node, a positioning accuracy for the wireless node; and estimating a position of the wireless node based on at least one first measurement of a first reference signal, the PRS, and the determined positioning accuracy. ### Claim 28 (depends on 15) The apparatus of claim 15, further comprising: means for determining a configuration of the PRS is based on a virtual cell identifier (VCID) of the apparatus. ### Claim 29 (depends on 26) The apparatus of claim 26, wherein the processing system is further configured to: obtain a second measurement of the PRS from another wireless node having a known location; and estimate the position based further on the second measurement and the known location. ### Claim 30 (depends on 27) The non-transitory computer-readable medium of claim 27, wherein the code further comprises instructions for: obtaining a second measurement of the PRS from another wireless node having a known location; and estimating the position based further on the second measurement and the known location.