This letter shows the first carrier phase tracking and positioning results with Starlink's low earth orbit (LEO) satellite signals. An adaptive Kalman filter based algorithm for beat from unknown Starlink signals is proposed. Experimental show of six satellites a horizontal error 7.7 m known receiver altitude.

Exploiting cellular long-term evolution (LTE) downlink signals for navigation purposes is considered. First, the transmitted LTE signal model presented and relevant positioning timing information that can be extracted from these are identified. Second, a software-defined receiver (SDR) capable of acquiring, tracking, producing pseudoranges designed. Third, threshold-based approach detecting first peak channel impulse response proposed in which threshold adapts to environmental noise level....

Global navigation satellite systems (GNSSs) have been the prevalent positioning, navigation, and timing technology over past few decades. However, GNSS signals suffer from four main limitations.

A framework for ground vehicle localization that uses cellular signals of opportunity (SOPs), a digital map, an inertial measurement unit (IMU), and Global Navigation Satellite System (GNSS) receiver is developed. This aims to enable in urban environment where GNSS could be unusable or unreliable. The proposed employs extended Kalman filter (EKF) fuse pseudorange observables extracted from SOPs, IMU measurements, GNSS-derived position estimates (when available). EKF coupled with map-matching...

This letter shows the first acquisition, Doppler tracking, and positioning results with Starlink's low Earth orbit satellite signals. A generalized-likelihood-ratio-based test is proposed to acquire downlink Kalman-filter-based algorithm for tracking frequency from unknown Starlink signals developed. Experimental show of six satellites, achieving a horizontal error 10 m.

A framework for opportunistic navigation with multi-constellation low Earth orbit (LEO) satellite signals is proposed. receiver architecture suitable processing both time division (TDMA) and frequency multiple access (FMDA) from Orbcomm Iridium NEXT satellites presented to produce Doppler measurements LEO satellites. An extended Kalman filter (EKF)-based estimator formulated solve a stationary receiver's position using the resulting measurements. Experimental results are showing positioning...

A navigation framework with carrier phase differential measurements from megaconstellation low Earth orbit (LEO) satellite signals is developed. The measurement errors due to ephemeris and ionospheric tropospheric delays are derived the statistics of dilution precision characterized. Moreover, joint probability density function LEO satellites' azimuth elevation angles 1) enable performance characterization frameworks satellites in a computationally efficient way 2) facilitate parameter...

A framework for positioning with low Earth orbit (LEO) satellite signals is proposed. The employs an extend Kalman filter (EKF) to estimate a receiver's position using Doppler frequency measurements from LEO satellites. satellites' positions and velocities are known through two-line element (TLE) files. receiver architecture acquire track extract satellites discussed. Simulation results show that 11 m accuracy can be achieved 25 Experimental presented demonstrating the proposed stationary...

A framework that could achieve submeter-level unmanned aerial vehicle (UAV) horizontal navigation in multipath-free environments with cellular carrier phase measurements is developed. This exploits the "loose" synchronization between base transceiver station (BTS) clocks. It shown through extensive experimental data beat frequency stability of BTSs approaches atomic standards and clock deviations can be realized as a stable autoregressive moving average model. BTS model referred to loose...

A method for achieving lane-level localization in global navigation satellite system (GNSS)-challenged environments is presented. The proposed uses the pseudoranges drawn from unknown ambient cellular towers as an exclusive aiding source a vehicle-mounted light detection and ranging (lidar) sensor. following scenario considered. vehicle its lidar with GNSS signals enters environment where these become unusable. equipped receiver capable of producing to environment. These are fused through...

A framework for navigation using cellular code division multiple access (CDMA) signals is studied in this paper. Theoretical lower bounds on the performance pseudorange measurements drawn from CDMA base transceiver stations (BTSs) are derived. Moreover, a mapper/navigator presence of timing discrepancies between mapper and navigator. In framework, mapping receiver (mapper) estimates stochastic dynamic clock biases BTSs shares these with navigating (navigator). The optimal analyzed, practical...

A software-defined receiver (SDR) for navigation using cellular code-division multiple access (CDMA) signals is presented. The forward link signal structure described, and models the transmitted received are developed. Particular attention paid to relevant information that could be extracted subsequently exploited positioning timing purposes. pseudorange from proposed modeled error studied in an additive white Gaussian channel. Experimental results with aerial ground vehicles utilizing SDR...

An opportunistic framework to navigate with differential carrier phase measurements from megaconstellation low Earth orbit (LEO) satellite signals is proposed. A computationally efficient integer ambiguity resolution algorithm proposed reduce the size of least-squares (ILS) problem, whose complexity grows exponentially number satellites. The Starlink constellation used as a specific example demonstrate efficacity algorithm, showing 60% reduction in ILS problem. joint probability density...

The navigation performance with low Earth orbit (LEO) satellite signals is evaluated. framework used to perform this evaluation tightly integrates a vehicle’s inertial system (INS) Doppler and pseudorange measurements from LEO satellites. following scenario considered. A vehicle has access global (GNSS) priori, uncertain information about states. navigates by integrating GNSS its onboard INS. During the period when are available, tracks satellites measurements, refining estimates their Next,...

I am not afraid of the GPS jammer, as long there are ambient signals opportunity (SOPs) to exploit in environment. In environments where challenged (e.g., indoors and deep urban canyons) or denied under jamming spoofing attacks), SOPs could serve an alternative positioning, navigation, timing (PNT) source GPS, more generally, global navigation satellite systems (GNSS). This article presents a radio simultaneous localization mapping (radio SLAM) approach that enables exploitation for...

This paper presents two frameworks for precise unmanned aerial vehicle (UAV) navigation with cellular carrier phase measurements. The first framework relies on a mapping UAV and navigating sharing Experimental results show that 63.06 cm position root mean-square error (RMSE) is achieved this framework. second leverages the relative stability of base transceiver station (BTS) clocks, which alleviates need mapper. It was shown through experimental data beat frequency BTSs approaches atomic...

This paper presents low-level models of cellular LTE signals along with an architecture for a software-defined radio (SDR) that is capable (1) extracting the essential parameters navigation from received and (2) acquiring tracking real transmit-ted multiple base stations. Moreover, method obtaining time-of-arrival (TOA) estimates highly robust against interference noise in environment presented. relies on estimating channel impulse response signal. The proposed SDR evaluated ground vehicle...

This article presents a framework for opportunistic unmanned aerial vehicle (UAV) navigation by exploiting carrier phase measurements from ambient cellular signals of opportunity. In the proposed framework, base transceiver stations (BTSs) are not assumed to be synchronous. A complete that employs an extended Kalman filter (EKF) is presented, including initialization and process measurement noise covariance selection. The EKF estimates position velocity UAV, as well differences between...

A neural network (NN)-based delay-locked loop (DLL) for multipath mitigation in Global Positioning System (GPS) receivers is developed. The NN operates on equally-spaced samples of the autocorrelation function. trained using a statistical distribution model that takes into consideration time delay and power attenuation. performance proposed method compared numerically experimentally with three other conventional techniques: early-minus-late DLL, narrow correlator, high resolution correlator....

A Doppler tracking and beacon detection framework for blind opportunistic navigation (BON) with low Earth orbit (LEO) satellite signals is proposed. The BON cognitively deciphers partially known of opportunity (SOPs) exploits them purposes. When only the bandwidth length an Mary phase shift keying (MPSK) SOP available, enables acquisition terrestrial space-based SOPs in a fashion. computationally efficient algorithm presented to blindly detect estimate frequency. applied decipher C/A...

This letter presents the first user equipment (UE)-based 5G navigation framework that exploits "on-demand" downlink signals. In this framework, entire system bandwidth of incoming signals is utilized in an opportunistic fashion. The proposed involves a cognitive approach to acquire so-called ultimate reference signal (URS), which includes as well "always-on" (RSs). Experimental results are presented showing acquired URS: (i) spans bandwidth, (ii) increases carrier-to-noise ratio by 10 dB...

A framework for simultaneously tracking Orbcomm low Earth orbit (LEO) satellites and using Doppler measurements drawn from their signals to aid a vehicle's inertial navigation system (INS) is developed. The developed enables navigating vehicle exploit ambient LEO satellite signal its INS in tightly-coupled fashion the event global (GNSS) become unusable. An overview of extended Kalman filter-based simultaneous (STAN) provided. Experimental results are presented showing an unmanned aerial...

A detailed software-defined receiver (SDR) architecture for navigation using cellular code division multiple access (CDMA) signals is presented. The forward-link signal structure described and models the transmitted received are developed. Particular attention paid to relevant information that could be extracted subsequently exploited timing purposes. differences between a typical GPS proposed CDMA highlighted. Moreover, framework based on mapping/navigating scheme in environment studied....