Abstract: Apparatuses, methods, and systems are described for a receiver of signals from one or more satellite navigational systems to detect and/or eliminate impaired satellites/signals and/or “false positives” from the set of satellites being estimated/acquired. One method includes acquiring coarse position, time, and frequency values for each of a plurality of satellites from one or more satellite navigational systems and then selecting a set of satellites based on whether one or more of their corresponding acquired coarse values are within a minimum range. An intersection point of the position domain correlograms generated from vectors of each satellite in the selected set is determined and, using that intersection point, satellites/signals are eliminated from the selected set of satellites.

Abstract: Apparatuses, methods, and systems are described for a receiver of signals from one or more satellite navigational systems to detect and/or eliminate impaired satellites/signals and/or “false positives” from the set of satellites being estimated/acquired. One method includes acquiring coarse position, time, and frequency values for each of a plurality of satellites from one or more satellite navigational systems and then selecting a set of satellites based on whether one or more of their corresponding acquired coarse values are within a minimum range. An intersection point of the position domain correlograms generated from vectors of each satellite in the selected set is determined and, using that intersection point, satellites/signals are eliminated from the selected set of satellites.

Abstract: Methods and apparatuses for a receiver of signals from one or more satellite navigational systems to detect and/or eliminate impaired satellites from the set of estimated/acquired satellites in view are described. One method includes acquiring coarse position, time, and frequency values for each of a plurality of satellites from one or more satellite navigational systems, the plurality of satellites being those currently estimated to be in view of the receiver; determining whether one or more of the acquired coarse values are within a minimum range; and if it is determined that the one or more acquired coarse values are within the minimum range: determining a pseudo-true peak of a position domain correlogram comprising Line of Sight (LOS) vectors of each of the plurality of satellites; and identifying any satellite whose cross-correlation peak is beyond a maximum distance from the pseudo-true peak as an impaired satellite.

Abstract: Methods and apparatuses for a receiver of signals from one or more satellite navigational systems to detect and/or eliminate impaired satellites from the set of estimated/acquired satellites in view are described. One method includes acquiring coarse position, time, and frequency values for each of a plurality of satellites from one or more satellite navigational systems, the plurality of satellites being those currently estimated to be in view of the receiver; determining whether one or more of the acquired coarse values are within a minimum range; and if it is determined that the one or more acquired coarse values are within the minimum range: determining a pseudo-true peak of a position domain correlogram comprising Line of Sight (LOS) vectors of each of the plurality of satellites; and identifying any satellite whose cross-correlation peak is beyond a maximum distance from the pseudo-true peak as an impaired satellite.

Abstract: Systems, methods, and apparatuses are provided for compensating for ionospheric delay in multi constellation Global Navigation Satellite Systems (GNSSs). In one method, a single Radio Frequency (RF) path receiver receives a first signal at a first frequency from a first satellite in a first GNSS constellation, receives a second signal at a second frequency from a second satellite in a second GNSS constellation, and calculates the ionospheric delay using the received first signal and the received second signal.

Abstract: Systems, methods, and apparatuses for a satellite navigational system receiver to select a subset of tracking satellites from the satellites in view are described. In one method, after selecting the satellite with a highest elevation, satellites are selected for the tracking subset by searching the sectors of an azimuth plane map in sequence.

Abstract: According to certain aspects, the invention includes using acquisition channel results from a number of satellites to achieve composite weak acquisition. According to certain other aspects, the invention also includes solving for an improved position estimate and, with a sufficiently accurate, either initial or improved position estimate, also solving for GPS system time using a composite of acquired signals from a plurality of satellites. Within commonly experienced initial position and time uncertainties, the geometric range changes are fairly linear, which allows the point of convergence of ranges to solve for GPS position and subsequently for time with reasonable accuracy, which is the equivalent to obtaining frame sync without any data demodulation or preamble matching.

Abstract: Systems, methods, and apparatuses are provided for compensating for ionospheric delay in multi constellation Global Navigation Satellite Systems (GNSSs). In one method, a single Radio Frequency (RF) path receiver receives a first signal at a first frequency from a first satellite in a first GNSS constellation, receives a second signal at a second frequency from a second satellite in a second GNSS constellation, and calculates the ionospheric delay using the received first signal and the received second signal.

Abstract: Systems, methods, and apparatuses for a satellite navigational system receiver to select a subset of tracking satellites from the satellites in view are described. In one method, after selecting the satellite with a highest elevation, satellites are selected for the tracking subset by searching the sectors of an azimuth plane map in sequence.

Abstract: According to certain aspects, the invention includes using acquisition channel results from a number of satellites to achieve composite weak acquisition. According to certain other aspects, the invention also includes solving for an improved position estimate and, with a sufficiently accurate, either initial or improved position estimate, also solving for GPS system time using a composite of acquired signals from a plurality of satellites. Within commonly experienced initial position and time uncertainties, the geometric range changes are fairly linear, which allows the point of convergence of ranges to solve for GPS position and subsequently for time with reasonable accuracy, which is the equivalent to obtaining frame sync without any data demodulation or preamble matching.