A device that includes a receiver that receives multiple positioning signals from a satellite, including a positioning signal and remaining positioning signals, and a processor communicatively coupled to the receiver. The processor determines a speed value of the device based on a Doppler shift of the positioning signal. The speed value is a magnitude of a velocity of the device in a direction. The processor also determines that the speed value is not consistent with at least one other measurement and determines the position of the device using the remaining positioning signals.

An assisted satellite positioning system based on detecting signals from a number of satellites includes: (a) a mobile receiver; and (b) a base station communicating with the receiver over a low-power wireless communication network, the base station providing ephemeris data of a selected number of the satellites, but not all, using a compressed data format. The ephemeris data may include data concerning doppler frequency variations or elevation variations of the selected satellites over a predetermined time interval. The doppler frequency variations and the elevation variations may be represented in the compressed format by coefficients of a polynomial function of time. The polynomial function may be weighted to have lesser relative errors in larger doppler frequencies than lesser doppler frequencies, or to have lesser relative errors in lesser elevations than larger elevations. In one implementation, the low-power wireless communication network—such as a LoRa network—that has a range of at least 10 miles.

The approach presented here relates to a method for detecting a group runtime variation for a navigation sensor for a navigation system for a vehicle. The method comprises a step of reading and a step of determining. In the reading step, at least one first GNSS simulator signal is read from a virtual satellite of a virtual global navigation satellite system at a first time and a second GNSS simulator signal is read from the virtual satellite or from at least one second virtual satellite of the virtual navigation satellite system at a second time different to the first time by means of a read device. The group runtime variation is determined using the first GNSS simulator signal and the second GNSS simulator signal in the determining step.

The present disclosure relates to a method for performing a parallel search for a first positioning fix in a Global Navigation Satellite System (GNSS) receiver. The method includes, in some instances, determining prepositioning information, wherein the prepositioning information includes a receiver information and a satellite information for each satellite in a plurality of satellites. The method further includes determining a code phase search range and a frequency search range, based on the prepositioning information, for each satellite in the plurality of satellites. The method further includes determining a starting point information for each satellite in the plurality of satellites, wherein each respective starting point information is representative of an offset from a center of a search range of the respective satellite. The method further includes performing the parallel search for all satellites in the plurality of satellites based on the respective code phase search range, the respective frequency search range and the respective starting point information.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

A method for generating a feature-based localization map for a global navigation satellite system (GNSS) -based localization and/or a feature-based localization includes generating feature information for the feature-based localization map using at least one GNSS information, generating GNSS-related meta-information that allows inferences to be drawn about a GNSS situation on which the generation of the feature information was based, and assigning the generated GNSS-related meta-information to the generated feature information.

A method or system can include or be configured to receive a set of satellite observations, receiving sensor data, determining a position estimate and associated positioning error for a rover based on the set of satellite observations and the sensor data, determine a protection level associated with the position estimate based on a set of potential faults, and optionally provide an alert when the positioning error exceeds the protection level.

A multipath suppression method based on a steepest descent method includes stripping, according to carrier Doppler shift information fed back by a phase-locked loop, a carrier from an intermediate-frequency signal input into a tracking loop; constructing, on the basis of the autocorrelation characteristics of a ranging code, a quadratic cost function related to a measurement deviation of the ranging code, the cost function being not affected by a multipath signal; and finally, designing a new tracking loop of the ranging code according to the quadratic cost function and the principle of the steepest descent method, such that the loop has a multipath suppression function without increasing the computational burden. Compared with a narrow-distance correlation method, the current method reduces computing resources by ⅓, the design and adjustment of parameters are simple and feasible, a multipath suppression effect is superior, and a high engineering application value is obtained.

An electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, is processed for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that defines a rate-line having a rate-line frequency that is related to the bauded signal and to the motion of the transmitter relative to the receiver. The rate-line frequency is tracked in time to generate data indicative of Doppler shift associated with the satellite. The data are then supplied to a tracking receiver.

A method for compensating for the absence of GPS data during a period of GPS signal loss in determining travel mileage of a vehicle includes: detecting vehicle motion using an accelerometer during a period of time in which a GPS tracking device is unable to determine a location of the vehicle due to loss of GPS signal; determining a first location of the vehicle corresponding to the last known GPS location data point stored in memory; determining a second location of the vehicle corresponding to a point at which the GPS signal is reacquired; and calculating the distance between the first and second locations based on a straight-line distance calculation between the first and second locations, or based on the use of geospatial mapping data to plot a roadway route between the first and second locations.