Abstract: The technology disclosed teaches a method of path planning using a GNSS Forecast, requesting the GNSS Forecast of signal obscuration on behalf of a vehicle travelling in a region, receiving and using the Forecast to plan a path or route that has GNSS signals available over the path or route that satisfy a predetermined criterium. Also taught are GNSS Forecasts and planned paths or routes for a plurality of flying vehicles used by a flight control system, requesting the GNSS Forecast of signal obscuration on behalf of a flying autonomous or automated vehicle travelling in a region, receiving and using the Forecast and to plan a path with GNSS signals available over the path that satisfy predetermined criteria including accommodating real-time changes in flight paths, without leaving space, that satisfies the predetermined criteria. Also taught is certifying performance of GNSS receivers used on a flying vessel.

Abstract: The disclosed technology for preparing digital samples for synthesis of RF to simulate channels and GNSS satellites using GPUs includes receiving simulated position and velocity of an antenna, dividing the cycle into points to be converted into the synthesized signal, and computing the points. A first LUT includes pseudo random sequences combinable to produce a code that varies over time for encoding the channel, and a second LUT specifies linear combinations of the pseudo random sequences in the first LUT that produce channel codes to produce the digital sample points. Also included is using GPUs to generate the channel code for a point by mapping the channel code and time position, combining the code with data to be encoded, repeatedly applying the using and combining to produce points, using multiple GPU cores to encode sample points concurrently in the cycle, and sending an ordered sequence of points to a converter.

Abstract: The disclosed technology teaches simulating new satellite messages for a GNSS simulation, providing a configuration file and programming script file, neither of which is pre-compiled into GNSS simulation code, that specify format for a message for a satellite and message format combination not yet operational or not yet compiled into the GNSS simulation code. Included is reading and applying the configuration file and running a script from the programming script file to generate navigation data for simulating positioning messages during the GNSS simulation and using the navigation data for simulating positioning signals during the GNSS simulation and testing of a GNSS receiver against the satellite and message format combination. The disclosed technology also teaches determining message format and values to use when simulating position signals by combining field format and field data values from a combination of the configuration files, almanac, ephemeris and related data, and the programming script files.

Abstract: Disclosed is a method of enhancing RTK position resolution using an RTK-enabled GNSS positioning receiver, including receiving an RTK base station signal for differential position calculation, and receiving a forecast assured navigation signal that includes data identifying line-of-sight availability of satellites generating GNSS signals at a position of the GNSS positioning receiver. Also included is excluding from, or reducing the weighting of, GNSS position calculation satellites not identified as line-of-sight available in the forecast assured navigation signal, and computing the GNSS position calculation combining the knowledge of line of sight, or not line of sight, satellites with the RTK base station signal to perform the differential position calculation and to determine an improved calculated position of the GNSS positioning receiver.

Abstract: The disclosed technology teaches simulating new satellite messages for a GNSS simulation, providing a configuration file and programming script file, neither of which is pre-compiled into GNSS simulation code, that specify format for a message for a satellite and message format combination not yet operational or not yet compiled into the GNSS simulation code. Included is reading and applying the configuration file and running a script from the programming script file to generate navigation data for simulating positioning messages during the GNSS simulation and using the navigation data for simulating positioning signals during the GNSS simulation and testing of a GNSS receiver against the satellite and message format combination. The disclosed technology also teaches determining message format and values to use when simulating position signals by combining field format and field data values from a combination of the configuration files, almanac, ephemeris and related data, and the programming script files.

Abstract: A method is provided for calibrating a test platform including a plurality of system outputs to align RF signals generated by the system outputs. RF power of a combined RF signal is detected, where the combined RF signal is from a reference RF signal generated by a reference system output in the plurality of system outputs and a test RF signal generated by a test system output in the plurality of systems outputs. A phase of the test RF signal is iteratively shifted relative to the reference RF signal until the detected RF power reaches a minimum. The test RF signal is inverted to be in-phase with the reference RF signal when the combined RF power reaches the minimum. A system is also provided for calibrating a test platform including a plurality of system outputs to align RF signals generated by the system outputs.

Abstract: Disclosed is a method of providing dilution of precision (DOP) forecasts for GNSS navigation and optionally degree of confidence, for routing of vehicles or alerting humans in vehicles: accessing a 3D map of an area including structure solids and generating cuboids in spaces not contained in the structure solids, and iteratively over time increments, calculating GNSS satellites visible from the cuboids using the 3D map and, using at least the calculated visibility, determining a DOP forecast for GNSS signals observable in the cuboids at the time increments. The disclosed method also includes compressing the calculated DOP forecast spatially and temporally, and distributing the compressed DOP forecast via a content delivery network (CDN), responsive to queries from requestors to an API of the CDN, whereby the requestors' systems can take into account the DOP forecast for routing the vehicles or alerting the humans in the vehicles to a predicted navigation impairment.

Abstract: The disclosed technology for preparing digital samples for synthesis of RF to simulate channels and GNSS satellites using GPUs includes receiving simulated position and velocity of an antenna, dividing the cycle into points to be converted into the synthesized signal, and computing the points. A first LUT includes pseudo random sequences combinable to produce a code that varies over time for encoding the channel, and a second LUT specifies linear combinations of the pseudo random sequences in the first LUT that produce channel codes to produce the digital sample points. Also included is using GPUs to generate the channel code for a point by mapping the channel code and time position, combining the code with data to be encoded, repeatedly applying the using and combining to produce points, using multiple GPU cores to encode sample points concurrently in the cycle, and sending an ordered sequence of points to a converter.

Abstract: Disclosed is a method of providing dilution of precision (DOP) forecasts for GNSS navigation and optionally degree of confidence, for routing of vehicles or alerting humans in vehicles: accessing a 3D map of an area including structure solids and generating cuboids in spaces not contained in the structure solids, and iteratively over time increments, calculating GNSS satellites visible from the cuboids using the 3D map and, using at least the calculated visibility, determining a DOP forecast for GNSS signals observable in the cuboids at the time increments. The disclosed method also includes compressing the calculated DOP forecast spatially and temporally, and distributing the compressed DOP forecast via a content delivery network (CDN), responsive to queries from requestors to an API of the CDN, whereby the requestors' systems can take into account the DOP forecast for routing the vehicles or alerting the humans in the vehicles to a predicted navigation impairment.

Abstract: The technology disclosed teaches a method of improving accuracy of a GNSS receiver that has a non-directional antenna, with the receiver sending CDN a request for predictive data for an area that includes the receiver. Responsive to the query, the method includes receiving data regarding LOS visibility for the receiver with respect to individual satellites, and the receiver using the data for satellite selection, for choosing some and ignoring other individual satellites. Also disclosed is using the data to exclude from satellite selection at least one individual satellite based on lack of LOS visibility to the individual satellite. Further disclosed is recognizing and rejecting spoofed GNSS signals received by a GNSS receiver that has a non-directional antenna, in response to a CDN response to a request for predictive data for an area that includes the receiver, with the receiver comparing the data with measures of signals received from individual satellites.

Abstract: The technology disclosed teaches a method of path planning using a GNSS Forecast, requesting the GNSS Forecast of signal obscuration on behalf of a vehicle travelling in a region, receiving and using the Forecast to plan a path or route that has GNSS signals available over the path or route that satisfy a predetermined criterium. Also taught are GNSS Forecasts and planned paths or routes for a plurality of flying vehicles used by a flight control system, requesting the GNSS Forecast of signal obscuration on behalf of a flying autonomous or automated vehicle travelling in a region, receiving and using the Forecast and to plan a path with GNSS signals available over the path that satisfy predetermined criteria including accommodating real-time changes in flight paths, without leaving space, that satisfies the predetermined criteria. Also taught is certifying performance of GNSS receivers used on a flying vessel.

Abstract: The disclosed technology teaches simulating new satellite messages for a GNSS simulation, providing a configuration file and programming script file, neither of which is pre-compiled into GNSS simulation code, that specify format for a message for a satellite and message format combination not yet operational or not yet compiled into the GNSS simulation code. Included is reading and applying the configuration file and running a script from the programming script file to generate navigation data for simulating positioning messages during the GNSS simulation and using the navigation data for simulating positioning signals during the GNSS simulation and testing of a GNSS receiver against the satellite and message format combination. The disclosed technology also teaches determining message format and values to use when simulating position signals by combining field format and field data values from a combination of the configuration files, almanac, ephemeris and related data, and the programming script files.

Abstract: The disclosed technology teaches testing an autonomous vehicle: shielding a GNSS receiving antenna of the vehicle from ambient GNSS signals while the vehicle is under test and supplanting the ambient GNSS signals with simulated GNSS signals. Testing includes using a GNSS signal generating system: receiving the ambient GNSS signals using an antenna of the system and determining a location and acceleration of the vehicle from the GNSS signals, accessing a model of an augmented environment that includes multi-pathing and obscuration of the GNSS signals along a test path, based on the determined location—generating the simulated GNSS signals to feed to the vehicle, in real time—simulating at least one constellation of GNSS satellite sources modified according to the augmented environment, based on the determined location, and feeding the simulated signals to a receiver in the vehicle, thereby supplanting ambient GNSS as the autonomous vehicle travels along the test path.

Abstract: A method is provided for calibrating a test platform including a plurality of system outputs to align RF signals generated by the system outputs. RF power of a combined RF signal is detected, where the combined RF signal is from a reference RF signal generated by a reference system output in the plurality of system outputs and a test RF signal generated by a test system output in the plurality of systems outputs. A phase of the test RF signal is iteratively shifted relative to the reference RF signal until the detected RF power reaches a minimum. The test RF signal is inverted to be in-phase with the reference RF signal when the combined RF power reaches the minimum. A system is also provided for calibrating a test platform including a plurality of system outputs to align RF signals generated by the system outputs.

Abstract: A method is provided for aligning RF signals of a first channel bank and additional channel banks in a test platform. A plurality of correlators is used to correlate a reference code signal carrying a particular code at a particular chip rate with a received code signal carrying the particular code at the particular chip rate from the first channel bank to establish a first timing offset. The plurality of correlators is used to correlate a continuation of the reference code signal with additional received code signals carrying the particular code at the particular chip rate from the additional channel banks to establish additional timing offsets. The first timing offset and additional timing offsets are applied to the first and additional channel banks. The plurality of correlators includes at least 12 correlators, and a timing offset is established in a correlation interval having a shorter duration than the particular code.

Abstract: An automated method is provided for suppressing spurious signals in a direct digital synthesized signal. To determine magnitudes of local oscillator (“LO”) feedthrough and image frequency signal components, a digitally synthesized RF signal is digitally analyzed. To reduce the magnitude of the LO feedthrough signal component, one or more first parameters of at least one digital-to-analog converter is automatically adjusted using a first search pattern. To reduce the magnitude of image frequency signal component, at least one second parameter of the at least one digital-to-analog converter is automatically adjusted and at least one third parameter of a phase compensation network is automatically adjusted using a second search pattern. The automatically adjusting for the LO feedthrough signal component and for the image frequency signal component can be iterated.

Abstract: A method is provided for aligning RF signals of a first channel bank and additional channel banks in a test platform. A plurality of correlators is used to correlate a reference code signal carrying a particular code at a particular chip rate with a received code signal carrying the particular code at the particular chip rate from the first channel bank to establish a first timing offset. The plurality of correlators is used to correlate a continuation of the reference code signal with additional received code signals carrying the particular code at the particular chip rate from the additional channel banks to establish additional timing offsets. The first timing offset and additional timing offsets are applied to the first and additional channel banks. The plurality of correlators includes at least 12 correlators, and a timing offset is established in a correlation interval having a shorter duration than the particular code.

Abstract: A method is provided for aligning RF signals of a first channel bank and additional channel banks in a test platform. A plurality of correlators is used to correlate a reference code signal carrying a particular code at a particular chip rate with a received code signal carrying the particular code at the particular chip rate from the first channel bank to establish a first timing offset. The plurality of correlators is used to correlate a continuation of the reference code signal with additional received code signals carrying the particular code at the particular chip rate from the additional channel banks to establish additional timing offsets. The first timing offset and additional timing offsets are applied to the first and additional channel banks. The plurality of correlators includes 72 correlators, and a timing offset established in a correlation interval having a shorter duration than a length of the particular code.

Abstract: An automated method is provided for suppressing spurious signals in a direct digital synthesized signal. To determine magnitudes of local oscillator (“LO”) feedthrough and image frequency signal components, a digitally synthesized RF signal is digitally analyzed. To reduce the magnitude of the LO feedthrough signal component for the LO feedthrough signal component, one or more first parameters of at least one digital-to-analogue converter is automatically adjusted following a first search pattern. To reduce the magnitude of image frequency signal component for the image frequency signal component, at least one second parameter of the at least one digital-to-analogue converter is automatically adjusted and at least one third parameter of a phase compensation network is automatically adjusted following a second search pattern. The automatically adjusting for the LO feedthrough signal component and for the image frequency signal component can be iterated.

Abstract: A method is provided for aligning RF signals of a first channel bank and additional channel banks in a test platform. A plurality of correlators is used to correlate a reference code signal carrying a particular code at a particular chip rate with a received code signal carrying the particular code at the particular chip rate from the first channel bank to establish a first timing offset. The plurality of correlators is used to correlate a continuation of the reference code signal with additional received code signals carrying the particular code at the particular chip rate from the additional channel banks to establish additional timing offsets. The first timing offset and additional timing offsets are applied to the first and additional channel banks. The plurality of correlators includes 72 correlators, and a timing offset established in a correlation interval having a shorter duration than a length of the particular code.