A receiver is arranged to receive a plurality of Global Navigation Satellite System (GNSS) signals from up to four different satellite navigation systems including a GLONASS system, a BeiDou system, a GPS system, and a Galileo system. Received GNSS signals are mixed with a first local frequency signal to generate a plurality of mixed signals. The mixed signals are processed in up to three parallel branches. In a first branch, a first portion of the mixed signals are transformed by passing the first portion through a band-pass filter having a bandwidth between about 0 MHz and 46 MHz and by amplifying the filtered signals with an AGC circuit. In a second branch, a second portion of the mixed signals are transformed by rejecting image signals of the second portion with an image rejection filter and mixing image rejection filter output signals with a second local frequency signal to derive first remixed signals. In a third branch, a third portion of the mixed signals are transformed by adjusting a phase of the third portion to overlap a band of the first remixed signals. The adjusted third portion of the mixed signals and the first remixed signals are concurrently band pass filtered with a low IF filter.

Various methods and apparatus relating to synchronizing location information between two or more devices are described. In some embodiments, the devices are both configured to generate GNSS receiver data that is synchronized to achieve greater location accuracy. In some embodiments, the GNSS receiver data can be weighted when one set of GNSS receiver data is known to have a higher accuracy than another set of GNSS receiver data.

Methods and systems are described for establishing high-accuracy absolute landmarks that can be used to locate a vehicle's location during a vehicle/HAAL interaction event in some embodiments. Comparing that information with GNSS satellite data allows GNSS satellite errors to be determined and either used by a first vehicle and/or conveyed to other vehicles in the region in some embodiments. Methods and systems are also described for obtaining effectively continuous values of intermittently measured road surface parameters that are determined over time by discrete measurements by systems in a plurality of vehicles in some embodiments.

A navigation system for a mobile object generates navigation data for the mobile object based on satellite navigation signals received from a plurality of satellites and base data received from a stationary base station. The navigation data includes code phase estimates and carrier phase estimates for the plurality of satellites. The system computes position, velocity and time estimates for the mobile object in accordance with the code phase estimates and carrier phase estimates, and performs a navigation function for the mobile object in accordance with the position, velocity and time estimates. The system generates code phase estimates by performing a Vector Delay Locked Loop (VDLL) computation process that drives a code NCO for each channel of a plurality of channels, and generates carrier phase estimates for the plurality of satellites by performing a RTK Vector Phase Locked Loop computation process that drives a carrier NCO for each channel.

The system and method facilitates Real-Time-Kinematic (RTK) GNSS with long baseline between a rover receiver and a base station receiver, even in the presence of scintillation or ionospheric disturbances that spatially fluctuate. Residual atmospheric errors can be estimated by a dual error model in a filter to promote efficient fixing or resolution of carrier phase ambiguities.

Systems and methods are provided for improving geolocation services, like GPS, using network device measurements. For example, a plurality of access points (APs) or other network devices may be implemented in a network environment and constructed with a GPS chip. Range measurements can be collected from these network devices and incorporated with the GPS locations using various methods described herein to improve the overall location determination of these devices.

The present disclosure relates to a precise point positioning (PPP) method performed by a satellite navigation device. In one embodiment, the method comprises: receiving multiple positioning signals from a plurality of navigation satellites of a satellite-based navigation system using a multi-frequency receiver; receiving space segment correction data for the navigation satellites of the satellite-based navigation system; separately requesting and receiving local assistance data, wherein the local assistance data represents atmospheric errors in the vicinity of the satellite navigation device; and computing at least one of a precise position or time based on the received positioning signals, the space segment correction data and the local assistance data. The present disclosure further relates to a satellite navigation device, method for providing assistance data to at least one satellite navigation device, an assistance server, a satellite-based positioning system, and a computer program.

The system and method facilitates Real-Time-Kinematic (RTK) GNSS with long baseline between a rover receiver and a base station receiver, even in the presence of scintillation or ionospheric disturbances that spatially fluctuate. Residual atmospheric errors can be estimated by a dual error model in a filter to promote efficient fixing or resolution of carrier phase ambiguities.

Perception data based multipath identification and correction is based on recognition that sensors such as radar, LIDAR, and cameras can generate perception data indicative of locations and properties of terrestrial objects in an environment surrounding a satellite navigation device (e.g., a GNSS receiver), which data may then be used in training, or updating, a model for determining or correcting distances to satellites to account for multipath. Multipath identification includes identifying multipaths to train the model, e.g., by using perception data to perform ray tracing. Multipath correction includes using the model to correct distance errors due to the multipaths or, equivalently, using the model to determine distances to satellites in a manner that accounts for the multipaths.

A space based multi-band GPS/GNSS navigation system, including: a first RF card with a space grade application specific integrated circuit (ASIC) implementing two RF channels configured to receive and process two different received navigation signals; a space grade navigation processor configured to: execute processor instructions to process the two different received navigation signals to produce position, velocity, and time information; and process measurements using an Extended Kalman filter for enhanced performance at high altitude, including cis-lunar and lunar space.