A Global Navigation Satellite System (GNSS) positioning techniques is provided. A method to improve the time required to compute a position measurement in a GNSS receiver, and the time required to make this position measurement accurate is also provided. The method comprises computing a snapshot PVT (Position Velocity and Time) measurement, and use it to reduce the time required to acquire new signals to compute a conventional PVT measurement. A receiver implementing the method is further provided.

A Global Navigation Satellite System (GNSS) positioning techniques is provided. A method to improve the time required to compute a position measurement in a GNSS receiver, and the time required to make this position measurement accurate is also provided. The method comprises computing a snapshot PVT (Position Velocity and Time) measurement, and use it to reduce the time required to acquire new signals to compute a conventional PVT measurement. A receiver implementing the method is further provided.

Various arrangements for compensating for Doppler shift on a non-terrestrial orthogonal frequency division multiplex (OFDM) network are presented. A received frequency of a downlink satellite message received from a satellite may be determined. A downlink frequency delta between an expected frequency of the downlink satellite message and the received frequency of the downlink satellite message can be calculated. An uplink frequency delta based on the calculated downlink frequency delta may be calculated. An uplink transmission frequency at which an uplink OFDM symbol is transmitted may be calculated based on the calculated uplink frequency delta.

A system and method to opportunistically receive and use measurements on a priori unknown radio signals, not intended for radio navigation or geolocation, in conjunction with aiding data to improve navigation/geolocation position and time estimation yield and accuracy.

Embodiments relate to a location server, a wireless device and methods performed therein for positioning the wireless device. The wireless device (120) is arranged to perform measurements associated to estimating the position of the wireless device (120), wherein the wireless device (120) is configured to: perform a code phase measurement on a satellite signal between a satellite and the wireless device (120), wherein the code phase measurement indicates a number of cycles of a code phase of the satellite signal, the number comprising a first integer part and a first fractional part; perform a carrier phase measurement on the first fractional part; and send to a location server (130) a report of the code phase measurement and the carrier phase measurement, for estimating the position of the wireless device (120).

A ranging code correlation function detection system for use in a global navigation satellite system (GNSS) receiver includes a correlation block to correlate a digitized GNSS signal (e.g. at or above a critical sampling rate) with a corresponding ranging code at each of a plurality of different offsets from a current estimate of a code delay to generate a plurality of correlation data points; an interpolation filter configured to generate at least one estimated correlation data point that lies between two of the correlation data points based on the current estimate of the code delay. In some cases the ranging code correlation function detection system may also include a discriminator block configured to generate an updated estimate of the code delay based on the at least one estimated correlation data point.

Disclosed embodiments facilitate accuracy and decrease error in terrestrial positioning systems, including errors induced by multipath (e.g. ground reflections) in doppler based measurements of SVs. In some embodiments, one or more Global Navigation Satellite System (GNSS) doppler measurements and one or more corresponding GNSS pseudorange measurements for one or more satellites may be obtained. One or more GNSS doppler estimates corresponding to the one or more GNSS doppler measurements may be determined, wherein for a GNSS doppler measurement, the corresponding GNSS doppler estimate may be determined based, in part, on the GNSS doppler measurement and a GNSS pseudorange measurement corresponding to the GNSS doppler measurement. A speed of the UE may be determined based, in part, on the one or more GNSS doppler estimates.

Various arrangements for compensating for Doppler shift on a non-terrestrial orthogonal frequency division multiplex (OFDM) network are presented. An absolute location of the UE instance may be determined. A relative velocity of the UE instance with respect to a satellite of the non-terrestrial OFDM network may be determined. A frequency delta due to Doppler shift may be determined. A transmission frequency at which an uplink OFDM symbol is to be transmitted to the satellite of the non-terrestrial OFDM network may be determined using the frequency delta.

A system and method for detection of an aerial drone in an environment includes a baseline of geo-mapped sensor data in a temporal and location indexed database formed by (i) using at least one sensor to receive signals from the environment and converting into digital signals for further processing; (ii) deriving time delays, object signatures, Doppler shifts, reflectivity, and/or optical characteristics from the received signals; (iii) geo-mapping the environment using GNSS and the sensor data; and (iv) logging sensor data over a time interval, for example 24 hours to 7 days. Live sensor data can be then be monitored and signature data can be derived by computing at least one parameter such as direction and signal strength. The live data is continuously or periodically compared to the baseline data to identify a variance, if any, which may be indicative of a detection event.

A position detection method to be executed by a computer, the position detection method includes transmitting, by a sensor terminal, a signal obtained by performing capture processing on a satellite signal from a satellite of a search target according to an order of the satellites of the search targets; calculating, by a calculation device, a position of the sensor terminal based on a signal transmitted by the sensor terminal; and determining a satellite having a highest discovery probability based on a specific estimation method for second and subsequent search targets, using an index which is reflected larger as the discovery probability of other satellites is higher or lower, in a case where the first satellite is captured when a first search target is determined.