Abstract: System and device configurations, and processes are provided for determining position based on low Earth orbit (LEO) satellite signals. Frameworks described herein can include performing Doppler frequency measurement for received quadrature phase shift keying (QPSK) signals. The framework may include channel tracking operations to determine Doppler shift measurements, a navigation filter operation to determine clock drift based on each Doppler shift measurement from each channel tracking loop, and determining position of a device based on LEO satellite signal sources. Frameworks described herein are also provided for carrier phase differential (CD)—low Earth orbit (LEO) (CD-LEO) measurements that may utilize a base and a rover without requiring prior knowledge of rover position. Embodiments can also cancel effects of ionospheric and tropospheric delays on the carrier phase and CD-LEO measurements.

Abstract: Systems, device configurations, and processes are provided for navigation and determination of navigation observables based on low Earth orbit (LEO) satellite signals. A method for navigation includes using differential carrier phase measurement of LEO signals including correction of position estimates using integer ambiguity resolution and double difference carrier phase determinations. Frameworks described herein can use a computationally efficient integer ambiguity resolution to reduce the size of the integer least squares (ILS) determination. The framework may include a joint probability density function (pdf) of the megaconstellation LEO satellites' azimuth and elevation angle to characterize a LEO system. Embodiments are also directed to correction of ambiguities of carrier phase differential (CD)-low Earth orbit (LEO) (CD-LEO) measurements that may utilize a base and a rover without requiring prior knowledge of rover position.

Abstract: Processes and device configurations are provided for navigation using communications signal observables and using differential and non-differential frameworks. Communication signals, such as cellular communication signals may be used to obtain position estimates of a device such as a rover or unmanned aerial vehicle. Frameworks are provided for determination of position estimates with and without the use of a base station device. Processes can include use of position estimates to aid navigation.

Abstract: This disclosure is directed to sub-meter level navigation accuracy for Unmanned Aerial Vehicles (UAVs) using broadband communication signals, such as cellular long-term evolution (LTE) signals. A framework and methods are provided using a receiver and controller to produce at least one of carrier phase, code phase, and Doppler frequency measurements from received LTE signals. Single difference measurements may be used to remove clock bias. LTE ENodeB clock biases are initialized using the known initial position of the UAV. The measurements are fused via an extended Kalman filter (EKF) to estimate the UAV position and integer ambiguities of the carrier phase single difference measurements. LTE signals can have different carrier frequencies and conventional algorithms do not estimate the integer ambiguities. Processes are described to detect cycle slip, where the carrier phase measurements from the LTE eNodeB multiple antenna ports are used to detect cycle slip.

Abstract: Systems, device configurations, and processes are provided for blind opportunistic navigation (BON) including cognitive deciphering of partially known signals of opportunity and blind Doppler estimation from LEO satellite signal. In one embodiment a method includes receiving a signal of opportunity and using a framework for BON. In one embodiment, the framework includes performing blind Doppler estimation and tracking, performing coherent integration, and performing blind beacon detection/tracking. Coherent integration may be performed once a blind estimate of the Doppler is produced, and detecting symbols of a beacon sequence is performed for at least one of acquiring, tracking, and navigating with the received signal of opportunity. According to another embodiment, a method for blind Doppler estimation, includes receiving a signal of opportunity, performing an initial wipe-off operation, performing a blind residual Doppler estimation, and performing a Doppler ambiguity resolution.

Abstract: Systems, device configurations, and processes are provided for tracking and navigation using low-earth orbit satellite (LEO) signals. Embodiments are provided to track LEO satellites in the absence or during interrupted service by global position sources (e.g., GNSS). Operations and a framework are provided to use low-earth orbit (LEO) downlink transmissions as a source of positioning data. Operations can include performing a Doppler frequency measurement on received satellite downlink transmissions to determine a pseudorange rate measurement for a vehicle relative to at least one LEO satellite. Pseudorange rate measurements may be used to correct vehicle position data of a vehicles inertial navigation system (INS) and for control/navigation of the vehicle. Embodiments allow for simultaneous tracking of LEO satellites and navigation of a vehicle, such as an unmanned aerial vehicle.

Abstract: Processes and device configurations, including a receiver structure, are provided to jointly estimate the time-of-arrival (TOA) and azimuth and elevation angles of direction-of-arrival (DOA) from signals of opportunity, such as received cellular long-term evolution (LTE) signals. In one embodiment, a matrix pencil (MP) algorithm is used to obtain a coarse estimate of the TOA and DOA. Tracking loop configurations are provided to refine the estimates and jointly track the TOA and DOA changes. One or more solutions are provided for acquisition and tracking in the presence of noise and multipath signals. Processes and devices configurations are provided to use refined estimates to determine position and for use in navigation of a device.

Abstract: Processes and device configurations are provided for extracting observables from communications signals. Methods include performing a frequency extraction on received communication signals to determine a carrier frequency, acquiring an estimation of channel frequency response and a frame start time. Signal tracking is performed to update frame start time of a signal physical broadcast channel block structure (SS/PBCH) in the communication signal, and at least one observable is extracted from the communications signal based on the updated estimate of frame start time. Characteristics of communications signal, such as frame structure including a synchronization signal physical broadcast channel block structure (SS/PBCH) may be used to opportunistically extract time of arrival (TOA) from communications signals. Symbols and subcarriers of new radio signals may be used to extract reference signals, and to determine one or more navigation observables based on communication signal.

Abstract: A spatial approach is provided to mitigate multipath error for an indoor pedestrian localization system using broadband communication signals, such as cellular long-term evolution (LTE) carrier phase measurements. Motion of a receiver may be used to synthesize an antenna array from time-separated elements. Received data may then be combined for synthetic aperture navigation that allows for suppressing multipath error based on determination of direction-of-arrival (DOA) of the incoming communication (e.g., LTE) signals. In one embodiment, navigation observables may be determined based on determined direction of arrival.

Abstract: Systems, device configurations, and processes are provided for tracking and navigation using low-earth orbit satellite (LEO) signals. Embodiments are provided to track LEO satellites in the absence or during interrupted service by global position sources (e.g., GNSS). Operations and a framework are provided to use low-earth orbit (LEO) downlink transmissions as a source of positioning data. Operations can include performing a Doppler frequency measurement on received satellite downlink transmissions to determine a pseudorange rate measurement for a vehicle relative to at least one LEO satellite. Pseudorange rate measurements may be used to correct vehicle position data of a vehicles inertial navigation system (INS) and for control/navigation of the vehicle. Embodiments allow for simultaneous tracking of LEO satellites and navigation of a vehicle, such as an unmanned aerial vehicle.

Abstract: System and device configurations, and processes are provided for determining position based on low Earth orbit (LEO) satellite signals. Frameworks described herein can include performing Doppler frequency measurement for received quadrature phase shift keying (QPSK) signals. The framework may include channel tracking operations to determine Doppler shift measurements, a navigation filter operation to determine clock drift based on each Doppler shift measurement from each channel tracking loop, and determining position of a device based on LEO satellite signal sources. Frameworks described herein are also provided for carrier phase differential (CD)—low Earth orbit (LEO) (CD-LEO) measurements that may utilize a base and a rover without requiring prior knowledge of rover position. Embodiments can also cancel effects of ionospheric and tropospheric delays on the carrier phase and CD-LEO measurements.

Abstract: Systems, device configurations, and processes are provided for navigation and determination of navigation observables based on low Earth orbit (LEO) satellite signals. A method for navigation includes using differential carrier phase measurement of LEO signals including correction of position estimates using integer ambiguity resolution and double difference carrier phase determinations. Frameworks described herein can use a computationally efficient integer ambiguity resolution to reduce the size of the integer least squares (ILS) determination. The framework may include a joint probability density function (pdf) of the megaconstellation LEO satellites' azimuth and elevation angle to characterize a LEO system. Embodiments are also directed to correction of ambiguities of carrier phase differential (CD)-low Earth orbit (LEO) (CD-LEO) measurements that may utilize a base and a rover without requiring prior knowledge of rover position.

Abstract: Systems, device configurations and methods are provided for indoor localization for a navigator receiver based on broadband communication signals such as LTE. In one embodiment, an LTE-IMU framework determines receiver position indoors. Two different designs of LTE receivers are provided based on code phase and carrier phase determinations of the received signal. A base/navigator framework is presented to correct unknown clock biases of the LTE eNodeBs. In this framework, the base receiver is placed outdoors, has knowledge of its own position, and makes pseudorange measurements to eNodeBs in the environment whose positions are known. The base transmits these pseudoranges to the indoor navigating receiver, which is also making pseudorange measurements to the same eNodeBs. The navigating receiver differences the base and navigator pseudoranges.

Abstract: This disclosure is directed to sub-meter level navigation accuracy for Unmanned Aerial Vehicles (UAVs) using broadband communication signals, such as cellular long-term evolution (LTE) signals. A framework and methods are provided using a receiver and controller to produce at least one of carrier phase, code phase, and Doppler frequency measurements from received LTE signals. Single difference measurements may be used to remove clock bias. LTE ENodeB clock biases are initialized using the known initial position of the UAV. The measurements are fused via an extended Kalman filter (EKF) to estimate the UAV position and integer ambiguities of the carrier phase single difference measurements. LTE signals can have different carrier frequencies and conventional algorithms do not estimate the integer ambiguities. Processes are described to detect cycle slip, where the carrier phase measurements from the LTE eNodeB multiple antenna ports are used to detect cycle slip.

Abstract: Processes and device configurations, including a receiver structure, are provided to jointly estimate the time-of-arrival (TOA) and azimuth and elevation angles of direction-of-arrival (DOA) from signals of opportunity, such as received cellular long-term evolution (LTE) signals. In one embodiment, a matrix pencil (MP) algorithm is used to obtain a coarse estimate of the TOA and DOA. Tracking loop configurations are provided to refine the estimates and jointly track the TOA and DOA changes. One or more solutions are provided for acquisition and tracking in the presence of noise and multipath signals. Processes and devices configurations are provided to use refined estimates to determine position and for use in navigation of a device.

Abstract: A spatial approach is provided to mitigate multipath error for an indoor pedestrian localization system using broadband communication signals, such as cellular long-term evolution (LTE) carrier phase measurements. Motion of a receiver may be used to synthesize an antenna array from time-separated elements. Received data may then be combined for synthetic aperture navigation that allows for suppressing multipath error based on determination of direction-of-arrival (DOA) of the incoming communication (e.g., LTE) signals. In one embodiment, navigation observables may be determined based on determined direction of arrival.

Abstract: Systems, device configurations and methods are provided for indoor localization for a navigator receiver based on broadband communication signals such as LTE. In one embodiment, an LTE-IMU framework determines receiver position indoors. Two different designs of LTE receivers are provided based on code phase and carrier phase determinations of the received signal. A base/navigator framework is presented to correct unknown clock biases of the LTE eNodeBs. In this framework, the base receiver is placed outdoors, has knowledge of its own position, and makes pseudorange measurements to eNodeBs in the environment whose positions are known. The base transmits these pseudoranges to the indoor navigating receiver, which is also making pseudorange measurements to the same eNodeBs. The navigating receiver differences the base and navigator pseudoranges.