# US 12,761,375 B2 · Regional position estimator for network devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,761,375 B2 - Document ID: US12761375B2 - Status: Granted - Kind: B2 - Application number: 18/466,716 - Filed: 2023-09-13 - Published: 2025-03-13 - Granted: 2026-10-13 - Earliest claimed: 2023-09-13 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Jerome Henry; Peiman Amini; Ardalan Alizadeh; Niloo Bahadori - Web page: https://patentgrep.com/patent/US12761375B2 ## CPC - G01S 19/42: Determining position - G01S 19/07: providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections - G01S 19/30: code related {(G01S19/246 takes precedence)} - G01S 19/48: by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system - G01S 19/50: whereby the position solution is constrained to lie upon a particular curve or surface, e.g. for locomotives on railway tracks - 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 Devices, systems, methods, and processes for accurately determining a location of a device are described herein. The device may receive Global Navigation Satellite System (GNSS) data from two satellites in two time periods. The device can determine two pseudo range differences corresponding to the two satellites. The device may further determine two contours based on the two pseudo range differences. An overlap between the two contours may be utilized by the device to determine the location. The device can also determine the location of the device based on a contour and an estimated location. The device may utilize a Global Positioning System (GPS) database, an Access Points (AP) database, or one or more servers to retrieve the estimated location. The device can further configure an operating frequency and an output power based on the location in real-time. ## Claims ### Claim 1 A device, comprising: a processor; a memory communicatively coupled to the processor; at least one global navigation satellite system (GNSS) receiver configured to receive a plurality of signals from one or more satellites; and a location identification logic, configured to: identify a first contour of geolocations; identify a second contour of geolocations; determine an area of overlap between the first contour and the second contour, wherein the area of overlap forms an ellipse in which a demi-major-axis (“DMA”) length depends on a number of GNSS measurements that the device collects before the one or more satellites move out of range; and determine a location of the device based on the area of overlap in real-time. ### Claim 2 (depends on 1) The device of claim 1, wherein the location identification logic is further configured to determine a first pseudo range difference based on a first signal and a second signal received from a first satellite, and wherein the first contour of geolocations is associated with the first pseudo range difference. ### Claim 3 (depends on 2) The device of claim 2, wherein the location identification logic is further configured to determine a second pseudo range difference is based on a third signal and a fourth signal received from a second satellite, and wherein the second contour of geolocations is associated with the second pseudo range difference. ### Claim 4 (depends on 3) The device of claim 3, wherein: the first signal and the second signal are received during a first time period, and the third signal and the fourth signal are received during a second time period. ### Claim 5 (depends on 4) The device of claim 4, wherein the device is stationary during the first time period and the second time period. ### Claim 6 (depends on 4) The device of claim 4, wherein the location identification logic is further configured to: receive a fifth signal from a third satellite, wherein the fifth signal includes a pseudo random code indicative of a satellite identifier and a timestamp; determine a clock drift based on the pseudo random code; and synchronize a local clock signal based on the clock drift. ### Claim 7 (depends on 6) The device of claim 6, wherein the location identification logic determines the first pseudo range difference and the second pseudo range difference based on the local clock signal. ### Claim 8 (depends on 6) The device of claim 6, wherein the device operates in a safe mode until the location of the device is determined. ### Claim 9 (depends on 4) The device of claim 4, wherein determining the first pseudo range difference comprises: receiving the first signal from the first satellite at a first time instant; extracting a first timestamp from the first signal; receiving the second signal from the first satellite at a second time instant; extracting a second timestamp from the second signal; determining a distance travelled by the first satellite in the first time period based on a difference between the first timestamp and the second timestamp; and determining the first pseudo range difference based on the distance travelled by the first satellite in the first time period. ### Claim 10 (depends on 4) The device of claim 4, wherein determining the second pseudo range difference comprises: receiving the third signal from the second satellite at a third time instant; extracting a third timestamp from the third signal; receiving the fourth signal from the second satellite at a fourth time instant; extracting a fourth timestamp from the second signal; determining a distance travelled by the second satellite in the second time period based on a difference between the third timestamp and the fourth timestamp; and determining the second pseudo range difference based on the distance travelled by the second satellite in the second time period. ### Claim 11 (depends on 3) The device of claim 3, wherein each of the first signal and the second signal received from the first satellite, and the third signal and the fourth signal received from the second satellite includes corresponding pseudo random code, corresponding almanac data, and corresponding ephemeris data. ### Claim 12 (depends on 1) The device of claim 1, wherein the location identification logic is further configured to determine an operating frequency and an output power level of the device based on the location of the device. ### Claim 13 (depends on 1) The device of claim 1, wherein the location of the device is refined based on a plurality of contours of geolocations determined for a plurality of pseudo range differences for a plurality of satellites. ### Claim 14 A device comprising: a processor; a memory communicatively coupled to the processor; at least one global navigation satellite system (GNSS) receiver configured to receive a plurality of signals from one or more satellites; and a location identification logic, configured to: identify a first contour of geolocations; retrieve an estimated location of the device; determine an area of overlap between the first contour and the estimated location, wherein the area of overlap forms an ellipse; and determine a location of the device based on the area of overlap in real-time. ### Claim 15 (depends on 14) The device of claim 14, further comprising determining a first pseudo range difference based on a first signal and a second signal received from a first satellite in a first time period, wherein the first contour of geolocations is associated with the first pseudo range difference. ### Claim 16 (depends on 15) The device of claim 15, wherein retrieving the estimated location comprises: querying a global positioning system (GPS) database of a plurality of fixed stations; determining a set of fixed stations from the plurality of fixed stations that observe the first pseudo range difference for the first satellite in the first time period; determining a closest fixed station from the set of fixed stations; and retrieving a location of the closest fixed station from the GPS database as the estimated location. ### Claim 17 (depends on 15) The device of claim 15, wherein retrieving the estimated location comprises: detecting one or more wireless signals with one or more access point identifiers; querying a crowd-sourced database of a plurality of access points and corresponding access point identifiers; identifying one or more access points based on the one or more access point identifiers; determining a closest access point from the one or more access points; and retrieving a location of the closest access point from the crowd-sourced database as the estimated location. ### Claim 18 (depends on 15) The device of claim 15, wherein retrieving the estimated location comprises: transmitting an echo request to a plurality of servers; receiving a plurality of responses from the plurality of servers; determining a round-trip time for each response; determining a server with lowest round-trip time; and extracting a location of the server with the lowest round-trip time from corresponding response as the estimated location. ### Claim 19 A method comprising: determining a first pseudo range difference based on a first signal and a second signal received by a device from a first satellite in a first time period; identifying a first contour of geolocations having the first pseudo range difference corresponding to the first satellite in the first time period; retrieving an estimated location of the device; determining an area of overlap between the first contour and the estimated location, wherein the area of overlap forms an ellipse; and determining a location of the device based on the area of overlap in real-time, wherein the device is stationary during the first time period. ### Claim 20 (depends on 19) The method of claim 19, wherein retrieving the estimated location is retrieved from at least one of: a Global Positioning System (GPS) database or a crowd-sourced database of a plurality of access points.