Secondary code determination in a snapshot receiver based upon transmission time alignment

    公开(公告)号:US11947019B2

    公开(公告)日:2024-04-02

    申请号:US17494249

    申请日:2021-10-05

    IPC分类号: G01S19/24 G01S19/43 G01S19/23

    摘要: The carrier phase ready coherent acquisition of a global navigation satellite system (GNSS) snapshot signal includes receiving in a snapshot receiver different GNSS signals from correspondingly different GNSS satellites, and performing multi-hypothesis (MH) acquisition upon each of GNSS signal in order to produce a complete set of secondary code index hypotheses, each hypothesis producing a corresponding acquisition result according to an identified peak at a correct code-phase and Doppler frequency. The secondary code index hypotheses are adjusted for each different GNSS signal based upon a flight time difference determined for each GNSS satellite, so as to produce a new set of hypotheses. Finally, one of the hypotheses in the new set may be selected as a correct hypothesis according to a predominate common index amongst the hypotheses in the new set, and the acquisition results for each of the different GNSS signals may be filtered utilizing the correct hypothesis.

    Bit transition enhanced direct position estimation in global satellite system positioning

    公开(公告)号:US11733393B2

    公开(公告)日:2023-08-22

    申请号:US17167936

    申请日:2021-02-04

    摘要: Embodiments of the present invention provide a method, system and computer program product for bit transition enhanced direct position estimation (DPE) from global navigation satellite system (GNSS) signals and includes the reception in a GNSS receiver of signals from multiple, different satellites in multiple satellite constellations adapted for use with the GNSS. The method estimates the GNSS receiver parameters position, velocity, clock bias, clock drift, and optionally and if unknown, the receiver time. The method generates a model of the received GNSS signals that depends on the receiver parameters. Uniquely, the method includes the synchronization of both a primary code and also a secondary code in the received GNSS signal model, in addition to time delays, Doppler shifts, and other relevant parameters for positioning. Finally, if the secondary code of a particular signal is unknown, the method determines the combination of bit transitions that maximizes the optimization problem.

    COLLABORATIVE DIFFERENTIAL GLOBAL NAVIGATION SATELLITE SYSTEM (GNSS)

    公开(公告)号:US20240302535A1

    公开(公告)日:2024-09-12

    申请号:US18120389

    申请日:2023-03-11

    IPC分类号: G01S19/07

    CPC分类号: G01S19/071 G01S19/072

    摘要: Differential global navigation satellite system (GNSS) positioning includes establishing a communicative coupling between a central computing node and a multiplicity of different roving receivers disposed within a geographic region of common atmospheric error. Each of the different roving receivers generates observable data from GNSS signals received from different ones of a selection of satellites in a GNSS constellation accessible from the geographic region of common atmospheric error. Differential GNSS additionally includes collecting the observable data from the different roving receivers in memory of the central computing node and computing a position of a specific one of the different roving receivers based upon a reduction of error determined from differencing performed upon the collected observable data from others of the different roving receivers. Finally, differential GNSS includes transmitting the computed position over the communicative coupling to the specific one of the roving receivers.

    BIT TRANSITION ENHANCED DIRECT POSITION ESTIMATION IN GLOBAL SATELLITE SYSTEM POSITIONING

    公开(公告)号:US20220244404A1

    公开(公告)日:2022-08-04

    申请号:US17167936

    申请日:2021-02-04

    摘要: Embodiments of the present invention provide a method, system and computer program product for bit transition enhanced direct position estimation (DPE) from global navigation satellite system (GNSS) signals and includes the reception in a GNSS receiver of signals from multiple, different satellites in multiple satellite constellations adapted for use with the GNSS. The method estimates the GNSS receiver parameters position, velocity, clock bias, clock drift, and optionally and if unknown, the receiver time. The method generates a model of the received GNSS signals that depends on the receiver parameters. Uniquely, the method includes the synchronization of both a primary code and also a secondary code in the received GNSS signal model, in addition to time delays, Doppler shifts, and other relevant parameters for positioning. Finally, if the secondary code of a particular signal is unknown, the method determines the combination of bit transitions that maximizes the optimization problem.

    TIME FREE POSITION DETERMINATION OF A ROVING RECEIVER USING A REFERENCE RECEIVER

    公开(公告)号:US20220196850A1

    公开(公告)日:2022-06-23

    申请号:US17127803

    申请日:2020-12-18

    摘要: A time-free position determination of a roving receiver includes acquiring from a snapshot receiver in a cloud executing process, a snapshot position of the snapshot receiver received by the snapshot receiver for a single epoch from a constellation of global positioning satellites, the snapshot position including a multiplicity of time-free observables. The method additionally includes retrieving into the cloud executing process baseline position data for a fixed receiver received from the constellation and comprising time-referenced observables. Finally, the method includes compositing in the cloud executing process the time-free observables of the snapshot position with the time referenced observables of the baseline position data to produce time and position data for the snapshot receiver.