# US 2014/0155082 A1 · Methods and Apparatus for Estimating Time of Arrival Information Associated with a Wireless Signal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0155082 A1 - Document ID: US20140155082A1 - Status: Published application - Kind: A1 - Application number: 13/689,973 - Filed: 2012-11-30 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Motorola Mobility LLC - Applicants: Motorola Mobility LLC - Inventors: Thomas P. Krauss; Michael J. Carney; Anthony R. Schooler - Web page: https://patentgrep.com/patent/US20140155082A1 ## CPC - H04W 24/02: Arrangements for optimising operational condition - G01S 5/0218: {Multipath in signal reception} - G01S 5/0221: {Receivers} - G01S 5/0273: {using multipath or indirect path propagation signals in position determination} - G01S 19/22: Multipath-related issues - G01S 5/10: Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements {, e.g. omega or decca systems}(G01S5/12 takes precedence {; beacons and receivers cooperating therewith G01S1/306, G01S1/308}) - G01S 5/14: Determining absolute distances from a plurality of spaced points of known location - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract Methods and apparatus for estimating time of arrival information associated with a wireless signal are disclosed. In an embodiment, a wireless device (102), or any other suitable device or system, determines a channel type based on multiple occurrences of a reference signal (700) (e.g., determine if a channel is delay-spread or non-delay-spread based on a ratio of largest peak to a mean of other peaks). The wireless device (102) then selects a time of arrival generator (800 or 900) based on the channel type (e.g., use delay-spread estimator if ratio is below threshold, and use non-delay-spread estimator if ratio is above threshold). The wireless device then (102) estimates the time of arrival information using the selected time of arrival generator (800 or 900) (e.g., sum peaks from multiple occasions and then estimate for delay-spread or estimate the time of arrival from each occasion and then average for non-delay-spread). ## Claims ### Claim 1 A method of estimating time of arrival information associated with a wireless signal, the method comprising: determining a channel type based on multiple occurrences of a reference signal; selecting a time of arrival generator based on the channel type; and estimating the time of arrival information using the selected time of arrival generator. ### Claim 2 (depends on 1) The method of claim 1, wherein determining the channel type based on multiple occurrences of the reference signal includes classifying a channel as one of (a) a delay-spread channel, and (b) a non-delay-spread channel. ### Claim 3 (depends on 2) The method of claim 2, wherein determining the channel type based on multiple occurrences of the reference signal includes determining a ratio of a first peak to a mean of a plurality of peaks, wherein the first peak is larger than each of the plurality of peaks. ### Claim 4 (depends on 3) The method of claim 3, wherein the plurality of peaks is determined by correlation of a received wireless signal with a reference signal. ### Claim 5 (depends on 3) The method of claim 3, wherein the ratio is a minimum ratio selected from a plurality of ratios. ### Claim 6 (depends on 5) The method of claim 5, wherein selecting the time of arrival generator based on the channel type includes selecting a first time of arrival generator if the ratio is not beyond a desired threshold. ### Claim 7 (depends on 6) The method of claim 6, wherein estimating the time of arrival information using the selected time of arrival generator includes summing peaks from multiple occasions to form a multi-occasion correlation, and estimating the time of arrival information based on the multi-occasion correlation. ### Claim 8 (depends on 5) The method of claim 5, wherein selecting the time of arrival generator based on the channel type includes selecting a second time of arrival generator if the ratio is beyond a desired threshold. ### Claim 9 (depends on 8) The method of claim 8, wherein estimating the time of arrival information using the selected time of arrival generator includes estimating a plurality of individual time of arrival estimates, each corresponding to the plurality of peaks from a measurement occasion, and estimating the time of arrival information based on the mean of the plurality of individual time of arrival estimates. ### Claim 10 (depends on 1) The method of claim 1, wherein the reference signal comprises a positioning reference symbol. ### Claim 11 (depends on 1) The method of claim 1, further comprising triangulating a physical position of a wireless device based on the time of arrival information. ### Claim 12 An apparatus for estimating time of arrival information associated with a wireless signal, the apparatus comprising: a radio frequency receiver structured to receive the wireless signal; and a controller, operatively coupled to the radio frequency receiver, the controller being structured to: classify a channel type based on multiple occurrences of a reference signal; select a time of arrival generator based on the channel type; and estimate the time of arrival information using the selected time of arrival generator. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the controller is structured to classify a channel as one of (a) a delay-spread channel, and (b) a non-delay-spread channel. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the controller is structured to determine a ratio of a first peak to a mean of a plurality of peaks, wherein the first peak is larger than each of the plurality of peaks. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the plurality of peaks is determined by correlation of a received wireless signal with a reference signal. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the ratio is a minimum ratio selected from a plurality of ratios. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the controller is structured to select a first time of arrival generator if the ratio is not beyond a desired threshold. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the controller is structured to sum peaks from multiple occasions to form a multi-occasion correlation, and estimate the time of arrival information based on the multi-occasion correlation. ### Claim 19 (depends on 16) The apparatus of claim 16, wherein the controller is structured to select a second time of arrival generator if the ratio is beyond a desired threshold. ### Claim 20 (depends on 19) The apparatus of claim 19, wherein the controller is structured to estimate a plurality of individual time of arrival estimates, each corresponding to the plurality of peaks from a measurement occasion, and estimating the time of arrival information based on the mean of the plurality of individual time of arrival estimates. ### Claim 21 (depends on 12) The apparatus of claim 12, wherein the reference signal comprises a positioning reference symbol. ### Claim 22 (depends on 12) The apparatus of claim 12, wherein a second controller is structured to triangulate a physical position associated with the apparatus based on the time of arrival information. ### Claim 23 A method of estimating time of arrival information associated with a wireless signal, the method comprising: classifying a channel as one of (a) a delay-spread channel, and (b) a non-delay-spread channel based on multiple occurrences of a positioning reference symbol from a plurality of antennas by determining a ratio of a first peak to a mean of a plurality of peaks, wherein the first peak is larger than each of the plurality of peaks, and the ratio is a minimum ratio selected from a plurality of ratios; if the ratio is not beyond a desired threshold, estimating the time of arrival information by summing each peak that occurs at a common time offset in the plurality of peaks from multiple occasions to form a multi-occasion correlation, and estimating the time of arrival information based on the multi-occasion correlation; and if the ratio is beyond the desired threshold, estimating the time of arrival information by estimating a plurality of individual time of arrival estimates, each corresponding to the plurality of peaks from one occasion, and estimating the time of arrival information based on the mean of the plurality of individual time of arrival estimates.