A method includes receiving, by an electronic device, a positioning request; responding to the positioning request; determining a target time source having the highest priority in at least two time sources; providing, for a GPS chip, a target time currently corresponding to the target time source; and performing GPS positioning based on the target time.

There is provided a method of parameter estimation in a multi-channel signal environment system wherein a plurality of receiving antennas receives signals or waves from one or more targets due to one or more transmitters that transmit a predetermined signal that is reflected back from the targets or receives signals that are directly transmitted from one or more external transmitters to the receiving antennas and then processed over multiple frequencies or channels by a digital receiver connected to one or more processors. The method comprises steps including (a) comparing received voltages to an analytic or a table driven calibrated channel model without only relying on information from lossy intermediate steps such as time of arrival (“TOA”) or angle of arrival (“AOA”) measurements; and (b) mitigating channel model calibration errors, including multiplicative channel noise, phase noise, clutter or multipath modeling errors, by using a noise model to estimate away error nuisance parameters, either during a prior calibration process or during a real time calibration process concurrent with localization and parameter estimation during normal system operation.

According to one or more embodiments herein, interferometry-based satellite location accuracy is provided. In one embodiment, a method comprises: determining, generally at a substantially given time, a reference satellite having a known accurate location within angular proximity of a communication satellite having a known general location; determining an accurate angular position of the communication satellite with relation to the reference satellite from the perspective of at least one ground station antenna of a known accurate location; determining an additional location reference measurement of the communication satellite; determining an accurate location of the communication satellite at the substantially given time based at least in part on the accurate angular position of the communication satellite with relation to the reference satellite from the perspective of the at least one ground station antenna and the additional location reference measurement of the communication satellite; and utilizing the accurate location of the communication satellite.

Methods and apparatuses for performing communication in a wireless communication system. A user equipment (UE) receives first satellite ephemeris information related to a first satellite and information related to a first validity duration corresponding to the first satellite from a base station; and restarts a first validity timer, based on second satellite ephemeris information related to the first satellite being received from the base station while the first validity timer having the first validity duration is running. The UE obtains a first TA for the first satellite based on the first satellite ephemeris information before the first validity timer restarts, expires, or stops after starting based on the first validity duration, and the UE obtains a second TA for the first satellite based on the second satellite ephemeris information before the first validity timer expires or stops after restarting based on a second validity duration.

A method and a user equipment (UE) for timing alignment is provided. The method comprises receiving, from a Base Station (BS), a first configuration indicating at least one of a scheduling offset, a common Timing Advance (TA), and satellite ephemeris information; receiving, from the BS, a second configuration indicating a TA offset for a TA variable; determining a UE-specific TA based on the satellite ephemeris information; determining a total TA based on at least one of the TA variable, the TA offset for the TA variable, the common TA, and the UE-specific TA; and starting, from a transmission by the UE, a time window after an additional time based on the total TA and the scheduling offset.

Methods and apparatuses for performing communication in a wireless communication system. A user equipment (UE) receives first satellite ephemeris information related to a first satellite and information related to a first validity duration corresponding to the first satellite from a base station; and restarts a first validity timer, based on second satellite ephemeris information related to the first satellite being received from the base station while the first validity timer having the first validity duration is running. The UE obtains a first TA for the first satellite based on the first satellite ephemeris information before the first validity timer restarts, expires, or stops after starting based on the first validity duration, and the UE obtains a second TA for the first satellite based on the second satellite ephemeris information before the first validity timer expires or stops after restarting based on a second validity duration.

Vehicles in traffic are expected to communicate wirelessly, to avoid collisions and facilitate the flow of traffic. Unfortunately, in 5G and 6G, the process of finding a wireless address of a specific vehicle is slow and difficult. Disclosed is a “connectivity matrix”, an emblem that vehicles can display, showing a pattern of black and white squares that forms a unique code. Another vehicle can autonomously read the code and look up the wireless address in a tabulation. The tabulation relates each code to the relevant wireless address, and optionally other information about the vehicle. The two vehicles can then transfer messages, including emergency messages, without delay. At freeway speeds, this can save lives. A central entity maintains the tabulation, ensuring that each wireless address is associated with a unique connectivity matrix code. Roadside companies and access points can also display a connectivity matrix, promote communication with prospective customers.

A system or method for generating or distributing GNSS corrections can include or operate to: generate a set of corrections based on satellite observations, wherein each correction of the set of corrections comprises an area associated with the correction, a tag, and correction data; update a set of stored corrections with the set of received corrections based on a tag associated with each correction of the set of stored corrections and the tag associated with each correction of the set of received corrections; and transmit stored corrections of the set of stored corrections to the GNSS receiver when the area associated with the stored corrections matches the locality of the GNSS receiver.

The carrier phase ready coherent acquisition of a global navigation satellite system (GNSS) snapshot signal includes receiving in a snapshot receiver different GNSS signals from correspondingly different GNSS satellites, and performing multi-hypothesis (MH) acquisition upon each of GNSS signal in order to produce a complete set of secondary code index hypotheses, each hypothesis producing a corresponding acquisition result according to an identified peak at a correct code-phase and Doppler frequency. The secondary code index hypotheses are adjusted for each different GNSS signal based upon a flight time difference determined for each GNSS satellite, so as to produce a new set of hypotheses. Finally, one of the hypotheses in the new set may be selected as a correct hypothesis according to a predominate common index amongst the hypotheses in the new set, and the acquisition results for each of the different GNSS signals may be filtered utilizing the correct hypothesis.

This disclosure relates generally to root zone moisture estimation for vegetation cover using remote sensing. Conventionally, it is challenging to estimate root zone soil moisture using only satellite data. Moreover, estimation of soil moisture under vegetation cover based on bare surface soil moisture and vegetation parameters is not available. The disclosed method and system facilitate estimation of an ensemble of soil moisture under vegetation cover and root zone soil moisture using process based soil water balance for spatial estimation of root zone soil moisture. The system estimates bare surface soil moisture for different soil types/textures using the baseline bare surface model and soil properties derived from satellite data and in-situ sensors. The method further provides temporal spatially distributed soil moisture inputs to an intelligent irrigation management/information system which is very important to reduce and regulate water consumption.