# US 10,871,576 B2 · Error mitigation in doppler based satellite positioning system measurements > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,871,576 B2 - Document ID: US10871576B2 - Status: Granted - Kind: B2 - Application number: 16/108,019 - Filed: 2018-08-21 - Published: 2019-11-21 - Granted: 2020-12-22 - Earliest claimed: 2018-05-16 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Gautam Nirula; William Morrison; Songwon Jee - Web page: https://patentgrep.com/patent/US10871576B2 ## CPC - G01S 19/40: Correcting position, velocity or attitude - G01S 19/22: Multipath-related issues - G01S 19/254: {relating to Doppler shift of satellite signals} - G01S 19/29: carrier {including Doppler,} related {(G01S19/246 takes precedence)} - G01S 19/52: Determining velocity - G01S 19/47: the supplementary measurement being an inertial measurement, e.g. tightly coupled inertial - G01S 19/49: whereby the further system is an inertial position system, e.g. loosely-coupled - 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 Disclosed embodiments facilitate accuracy and decrease error in terrestrial positioning systems, including errors induced by multipath (e.g. ground reflections) in doppler based measurements of SVs. In some embodiments, one or more Global Navigation Satellite System (GNSS) doppler measurements and one or more corresponding GNSS pseudorange measurements for one or more satellites may be obtained. One or more GNSS doppler estimates corresponding to the one or more GNSS doppler measurements may be determined, wherein for a GNSS doppler measurement, the corresponding GNSS doppler estimate may be determined based, in part, on the GNSS doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS doppler measurement. A speed of the UE may be determined based, in part, on the one or more GNSS doppler estimates. ## Claims ### Claim 1 A method of determining a speed of a user equipment (UE), the method comprising: measuring Global Navigation Satellite System (GNSS) Doppler measurements and corresponding GNSS pseudorange measurements for GNSS satellites; determining one or more GNSS Doppler estimates corresponding to the GNSS Doppler measurements, wherein for a GNSS Doppler measurement, a corresponding GNSS Doppler estimate is determined based, in part, on the GNSS Doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS Doppler measurement; and determining the speed of the UE based, at least in part, on the GNSS Doppler estimates. ### Claim 2 (depends on 1) The method of claim 1, wherein the corresponding GNSS Doppler estimate is determined based further on one or more GNSS environmental parameters associated with the GNSS Doppler measurement. ### Claim 3 (depends on 2) The method of claim 2, wherein the one or more GNSS environmental parameters associated with the GNSS Doppler measurement comprise one or more of: a GNSS timestamp associated with the GNSS Doppler measurement; or a GNSS position fix associated with the GNSS Doppler measurement; or a GNSS position fix uncertainty associated with the GNSS Doppler measurement; or a GNSS Heading and GNSS heading uncertainty associated with the GNSS Doppler measurement; or Dilution of Precision parameters associated with the GNSS Doppler measurement; or a type of position fix associated with the GNSS Doppler measurement. ### Claim 4 (depends on 1) The method of claim 1, wherein determining the corresponding GNSS Doppler estimate comprises: determining, for the GNSS Doppler measurement, a correction, wherein the correction is determined based on the GNSS Doppler measurement and the pseudorange measurement corresponding to the GNSS Doppler measurement; and applying the correction to the GNSS Doppler measurement to obtain the corresponding GNSS Doppler estimate. ### Claim 5 (depends on 4) The method of claim 4, wherein the correction is determined further based on at least one of: one or more Inertial Measurement Unit (IMU) measurements, or one or more sensor measurements by the UE. ### Claim 6 (depends on 4) The method of claim 4, wherein the correction is determined based on a mathematical model. ### Claim 7 (depends on 1) The method of claim 1, wherein determining the corresponding GNSS Doppler estimate comprises: predicting the corresponding GNSS Doppler estimate based on the GNSS Doppler measurement and the GNSS pseudorange measurement corresponding to the GNSS Doppler measurement, wherein the corresponding GNSS Doppler estimate is predicted using a predictive model based on machine learning. ### Claim 8 (depends on 7) The method of claim 7, wherein the predictive model is based on at least one of: a Generalized Additive Model (GAM), or a Recursive Neural Network (RNN), or a Convolutional Neural Network (CNN), or a Fully Connected Network (FCN), or an adaptive boosting model, or a Generative Adversarial Network (GAN), or a combination thereof. ### Claim 9 (depends on 7) The method of claim 7, wherein the corresponding GNSS Doppler estimate is predicted based in part on one or more of: Inertial Measurement Unit (IMU) measurements, or sensor measurements by the UE. ### Claim 10 (depends on 1) The method of claim 1, further comprising: determining, based on the speed of the UE over a time interval, a distance travelled by the UE. ### Claim 11 A User Equipment (UE) comprising: a Global Navigation Satellite System (GNSS) receiver capable of receiving GNSS signals, wherein the GNSS receiver is configured to measure GNSS Doppler measurements and corresponding GNSS pseudorange measurements for GNSS satellites; and a processor coupled to the GNSS receiver, wherein the processor is configured to: determine GNSS Doppler estimates corresponding to the one or GNSS Doppler measurements, wherein for a GNSS Doppler measurement, a corresponding GNSS Doppler estimate is determined based, in part, on the GNSS Doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS Doppler measurement; and determine a speed of the UE based, at least in part, on the GNSS Doppler estimates. ### Claim 12 (depends on 11) The UE of claim 11, wherein processor is configured to determine the corresponding GNSS Doppler estimate based further on one or more GNSS environmental parameters associated with the GNSS Doppler measurement. ### Claim 13 (depends on 12) The UE of claim 12, wherein the one or more GNSS environmental parameters associated with the GNSS Doppler measurement comprise one or more of: a GNSS timestamp associated with the GNSS Doppler measurement; or a GNSS position fix associated with the GNSS Doppler measurement; or a GNSS position fix uncertainty associated with the GNSS Doppler measurement; or a GNSS Heading and GNSS heading uncertainty associated with the GNSS Doppler measurement; or Dilution of Precision parameters associated with the GNSS Doppler measurement; or a type of position fix associated with the GNSS Doppler measurement. ### Claim 14 (depends on 11) The UE of claim 11, wherein to determine the corresponding GNSS Doppler estimate, the processor is configured to: determine, for the GNSS Doppler measurement, a correction, wherein the correction is determined based on the GNSS Doppler measurement and the pseudorange measurement corresponding to the GNSS Doppler measurement; and apply the correction to the GNSS Doppler measurement to obtain the corresponding GNSS Doppler estimate. ### Claim 15 (depends on 14) The UE of claim 14, wherein the correction is determined further based on at least one of: one or more Inertial Measurement Unit (IMU) measurements, or one or more sensor measurements by the UE. ### Claim 16 (depends on 14) The UE of claim 14, wherein the correction is determined based on a mathematical model. ### Claim 17 (depends on 11) The UE of claim 11, wherein to determine the corresponding GNSS Doppler estimate, processor is configured to: predict the corresponding GNSS Doppler estimate based on the GNSS Doppler measurement and the GNSS pseudorange measurement corresponding to the GNSS Doppler measurement, wherein the corresponding GNSS Doppler estimate is predicted using a predictive model based on machine learning. ### Claim 18 (depends on 17) The UE of claim 17, wherein the predictive model is based on at least one of: a Generalized Additive Model (GAM), or a Recursive Neural Network (RNN), or a Convolutional Neural Network (CNN), or a Fully Connected Network (FCN), or an adaptive boosting model, or a Generative Adversarial Network (GAN), or a combination thereof. ### Claim 19 (depends on 17) The UE of claim 17, wherein the corresponding GNSS Doppler estimate is predicted based in part on one or more of: Inertial Measurement Unit (IMU) measurements, or sensor measurements by the UE. ### Claim 20 (depends on 11) The UE of claim 11, wherein processor is further configured to: determine, based on the speed of the UE over a time interval, a distance travelled by the UE. ### Claim 21 A User Equipment (UE) comprising: means for measuring GNSS Doppler measurements and corresponding GNSS pseudorange measurements for GNSS satellites; means for determining one or more GNSS Doppler estimates corresponding to the GNSS Doppler measurements, wherein for a GNSS Doppler measurement, a corresponding GNSS Doppler estimate is determined based, in part, on the GNSS Doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS Doppler measurement; and means for determining a speed of the UE based, at least in part, on the GNSS Doppler estimates. ### Claim 22 (depends on 21) The UE of claim 21, wherein the corresponding GNSS Doppler estimate is determined based further on one or more GNSS environmental parameters associated with the GNSS Doppler measurement. ### Claim 23 (depends on 21) The UE of claim 21, wherein the means for determining the corresponding GNSS Doppler estimate comprises: means for determining, for the GNSS Doppler measurement, a correction, wherein the correction is determined based on the GNSS Doppler measurement and the pseudorange measurement corresponding to the GNSS Doppler measurement; and means for applying the correction to the GNSS Doppler measurement to obtain the corresponding GNSS Doppler estimate. ### Claim 24 (depends on 23) The UE of claim 23, wherein the correction is determined based on a mathematical model. ### Claim 25 (depends on 21) The UE of claim 21, wherein the means for determining GNSS Doppler estimates further comprises: means for predicting the corresponding GNSS Doppler estimate based on the GNSS Doppler measurement and the GNSS pseudorange measurement corresponding to the GNSS Doppler measurement, wherein the means for predicting the corresponding GNSS Doppler estimate comprises a predictive model based on machine learning. ### Claim 26 A non-transitory computer-readable medium comprising executable instructions that, when executed, cause to configure a processor on a User Equipment (UE) to: obtain measure one or more GNSS Doppler measurements and one or more corresponding GNSS pseudorange measurements for one or more GNSS satellites; determine one or more GNSS Doppler estimates corresponding to the one or more GNSS Doppler measurements, wherein for a GNSS Doppler measurement, a corresponding GNSS Doppler estimate is determined based, in part, on the GNSS Doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS Doppler measurement; and determine a speed of the UE based, at least in part, on the one or more GNSS Doppler estimates. ### Claim 27 (depends on 26) The computer-readable medium of claim 26, wherein the corresponding GNSS Doppler estimate is determined based further on one or more GNSS environmental parameters associated with the GNSS Doppler measurement. ### Claim 28 (depends on 26) The computer-readable medium of claim 26, wherein the executable instructions to determine the corresponding GNSS Doppler estimate further configure the processor to: determine, for the GNSS Doppler measurement, a correction, wherein the correction is determined based on the GNSS Doppler measurement and the pseudorange measurement corresponding to the GNSS Doppler measurement; and apply the correction to the GNSS Doppler measurement to obtain the corresponding GNSS Doppler estimate. ### Claim 29 (depends on 28) The computer-readable medium of claim 28, wherein the correction is determined based on a mathematical model. ### Claim 30 (depends on 26) The computer-readable medium of claim 26, wherein the executable instructions to determine the corresponding GNSS Doppler estimate further configure the processor to: predict the corresponding GNSS Doppler estimate based on the GNSS Doppler measurement and the GNSS pseudorange measurement corresponding to the GNSS Doppler measurement, wherein the corresponding GNSS Doppler estimate is predicted using a predictive model based on machine learning.