# US 2025/0093455 A1 · Graph-based facility navigation using rf fingerprints > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0093455 A1 - Document ID: US20250093455A1 - Status: Published application - Kind: A1 - Application number: 18/467,443 - Filed: 2023-09-14 - Published: 2025-03-20 - Earliest claimed: 2023-09-14 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Benjamin Tarlow; Murray Jarvis; Nicolas Graube - Web page: https://patentgrep.com/patent/US20250093455A1 ## CPC - G01S 5/02521: {using a radio-map} - G01C 21/206: {specially adapted for indoor navigation} - G01C 21/3446: {Details of route searching algorithms, e.g. Dijkstra, A*, arc-flags or using precalculated routes} - H04W 40/02: Communication route or path selection, e.g. power-based or shortest path routing - H04W 64/006: {with additional information processing, e.g. for direction or speed determination} - 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 - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract This disclosure provides systems, methods, and devices for wireless communication that support guidance of users to particular locations within a facility. In a first aspect, RF fingerprints are determined at locations within the facility based on signal strengths from RF devices, including electronic shelf labels (ESLs). A graph may be determined based on the RF fingerprints. A current location for a user may be determined based on a current RF fingerprint for the user. A route through the graph may be determined through the facility and may be displayed to the user as the user navigates the facility. Other aspects and features are also claimed and described. ## Claims ### Claim 1 A method comprising: determining a plurality of radio frequency (RF) fingerprints at corresponding locations within a facility, the plurality of RF fingerprints indicating signal strengths from RF devices at the corresponding locations, the RF devices including electronic shelf labels (ESLs); determining a graph based on the plurality of RF fingerprints; receiving a current RF fingerprint for a user within the facility; determining, based on the current RF fingerprint, a current location of the user within the graph; determining a route to a target product by traversing the graph from the current location to a target location for the target product; and displaying the route to a user while navigating the facility to the target location. ### Claim 2 (depends on 1) The method of claim 1, wherein the graph contains nodes corresponding to the RF fingerprints and edges connecting the nodes based on similarity measures between corresponding RF fingerprints. ### Claim 3 (depends on 2) The method of claim 2, wherein determining the current location of the user comprises determining, as the current location of the user, a closest matching node for the current RF fingerprint within the graph. ### Claim 4 (depends on 3) The method of claim 3, wherein the route is determined to contain a sequence of nodes within the graph connecting the closest matching node to the target location. ### Claim 5 (depends on 4) The method of claim 4, wherein the route is determined to traverse the graph from the current location to a target location with the fewest number of nodes, where edges connecting the sequence of nodes within the route meet a predetermined similarity requirement. ### Claim 6 (depends on 2) The method of claim 2, wherein the route is determined to traverse the graph from the current location to the target location while optimizing an average similarity measure for edges included in the route. ### Claim 7 (depends on 1) The method of claim 1, wherein the target location is an ESL corresponding to the target product. ### Claim 8 (depends on 1) The method of claim 1, wherein the plurality of RF fingerprints are measured by each of at least a subset of the ESLs. ### Claim 9 (depends on 1) The method of claim 1, wherein the plurality of RF fingerprints are determined based on maximum values of RF signals measured while moving through the facility. ### Claim 10 (depends on 1) The method of claim 1, wherein displaying the route includes (i) illuminating a sequence of ESLs along the route, (ii) displaying a progress indicator on a mobile device associated with the user, (iii) displaying a sequence of products along the route, or (iv) a combination thereof. ### Claim 11 A system comprising: a memory storing processor-readable code; and at least one processor coupled to the memory, the at least one processor configured to execute the processor-readable instructions to cause the at least one processor to perform operations comprising: determining a plurality of radio frequency (RF) fingerprints at corresponding locations within a facility, the plurality of RF fingerprints indicating signal strengths from RF devices at the corresponding locations, the RF devices including electronic shelf labels (ESLs); determining a graph based on the plurality of RF fingerprints; receiving a current RF fingerprint for a user within the facility; determining, based on the current RF fingerprint, a current location of the user within the graph; determining a route to a target product by traversing the graph from the current location to a target location for the target product; and displaying the route to a user while navigating the facility to the target location. ### Claim 12 (depends on 11) The system of claim 11, wherein the graph contains nodes corresponding to the RF fingerprints and edges connecting the nodes based on similarity measures between corresponding RF fingerprints. ### Claim 13 (depends on 12) The system of claim 12, wherein determining the current location of the user comprises determining, as the current location of the user, a closest matching node for the current RF fingerprint within the graph. ### Claim 14 (depends on 13) The system of claim 13, wherein the route is determined to contain a sequence of nodes within the graph connecting the closest matching node to the target location. ### Claim 15 (depends on 14) The system of claim 14, wherein the route is determined to traverse the graph from the current location to a target location with the fewest number of nodes, where edges connecting the sequence of nodes within the route meet a predetermined similarity requirement. ### Claim 16 (depends on 12) The system of claim 12, wherein the route is determined to traverse the graph from the current location to the target location while optimizing an average similarity measure for edges included in the route. ### Claim 17 (depends on 11) The system of claim 11, wherein the target location is an ESL corresponding to the target product. ### Claim 18 (depends on 11) The system of claim 11, wherein the plurality of RF fingerprints are measured by each of at least a subset of the ESLs. ### Claim 19 (depends on 11) The system of claim 11, wherein the plurality of RF fingerprints are determined based on maximum values of RF signals measured while moving through the facility. ### Claim 20 (depends on 11) The system of claim 11, wherein displaying the route includes (i) illuminating a sequence of ESLs along the route, (ii) displaying a progress indicator on a mobile device associated with the user, (iii) displaying a sequence of products along the route, or (iv) a combination thereof. ### Claim 21 A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform operations comprising: determining a plurality of radio frequency (RF) fingerprints at corresponding locations within a facility, the plurality of RF fingerprints indicating signal strengths from RF devices at the corresponding locations, the RF devices including electronic shelf labels (ESLs); determining a graph based on the plurality of RF fingerprints; receiving a current RF fingerprint for a user within the facility; determining, based on the current RF fingerprint, a current location of the user within the graph; determining a route to a target product by traversing the graph from the current location to a target location for the target product; and displaying the route to a user while navigating the facility to the target location. ### Claim 22 (depends on 21) The non-transitory computer-readable medium of claim 21, wherein the graph contains nodes corresponding to the RF fingerprints and edges connecting the nodes based on similarity measures between corresponding RF fingerprints. ### Claim 23 (depends on 22) The non-transitory computer-readable medium of claim 22, wherein determining the current location of the user comprises determining, as the current location of the user, a closest matching node for the current RF fingerprint within the graph. ### Claim 24 (depends on 23) The non-transitory computer-readable medium of claim 23, wherein the route is determined to contain a sequence of nodes within the graph connecting the closest matching node to the target location. ### Claim 25 (depends on 24) The non-transitory computer-readable medium of claim 24, wherein the route is determined to traverse the graph from the current location to a target location with the fewest number of nodes, where edges connecting the sequence of nodes within the route meet a predetermined similarity requirement. ### Claim 26 A guidance system comprising: a plurality of electronic shelf labels (ESLs); and a computing device configured to perform operations comprising: determining a plurality of radio frequency (RF) fingerprints at corresponding locations within a facility, the plurality of RF fingerprints indicating signal strengths from the plurality of ESLs; determining a graph based on the plurality of RF fingerprints; receiving a current RF fingerprint for a user within the facility; determining, based on the current RF fingerprint, a current location of the user within the graph; determining a route to a target product by traversing the graph from the current location to a target location for the target product; and displaying the route to a user while navigating the facility to the target location. ### Claim 27 (depends on 26) The guidance system of claim 26, wherein the graph contains nodes corresponding to the RF fingerprints and edges connecting the nodes based on similarity measures between corresponding RF fingerprints. ### Claim 28 (depends on 27) The guidance system of claim 27, wherein determining the current location of the user comprises determining, as the current location of the user, a closest matching node for the current RF fingerprint within the graph. ### Claim 29 (depends on 28) The guidance system of claim 28, wherein the route is determined to contain a sequence of nodes within the graph connecting the closest matching node to the target location. ### Claim 30 (depends on 29) The guidance system of claim 29, wherein the route is determined to traverse the graph from the current location to a target location with the fewest number of nodes, where edges connecting the sequence of nodes within the route meet a predetermined similarity requirement.