In certain embodiments, a wireless device obtains one or more NTN-related metrics for each of a plurality of cells in a non-terrestrial network and selects a cell for camping based at least in part on the one or more NTN-related metrics. The one or more NTN-related metrics comprise: a geographical distance between the wireless device and a reference point; a distance between the wireless device and the one or more satellites serving each cell; an RTT offered by the one or more satellites serving each cell; RTT variations in each cell; a requirement to pre-compensate the RTT by means of GNSS measurements; a velocity of the satellite serving each cell; an angle of elevation between the device and the satellite(s) serving each cell; a Doppler shift induced by the satellite serving each cell; a tracking area code broadcasted by the cell; and/or a signal strength/quality offset.

The disclosure concerns a method for providing GNSS sensor data, comprising at least the following steps: (a) receiving GNSS satellite signals; (b) evaluating the received GNSS satellite signals to ascertain GNSS sensor data; (c) rating the received GNSS satellite signals on the basis of at least one GNSS-specific performance criterion; and (d) associating a rating that results from step (c) with the related GNSS sensor data.

One example includes a passive radar receiver system including an RF receiver front-end to receive a wireless source signal and a reflected signal. An antenna switch of the front-end switches a first antenna to a receiver chain during a first time to generate first radar signal data based on a combined wireless signal comprising wireless source signal and the reflected signal, and switches a second antenna to the receiver chain during a second time to generate second radar signal data based on the combined wireless signal. A signal processor generates source signal data associated with the wireless source signal based on the first and second radar signal data and generates reflected signal data associated with the reflected signal based on the first and second radar signal data, and generates target radar data associated with a target based on the source and reflected radar signal data.

A positioning device receives multiple positioning signals respectively transmitted from multiple positioning satellites, changes a condition of the positioning satellites to be used in a positioning calculation processing based on a determination of whether a surrounding environment is an environment in which a multipath is likely to occur, and performs the positioning calculation processing by using the positioning signals from the positioning satellites that satisfy the condition.

A satellite system operates at altitudes between 100 and 350 km relying on vehicles including a self-sustaining ion engine to counteract atmospheric drag to maintain near-constant orbit dynamics. The system operates at altitudes that are substantially lower than traditional satellites, reducing size, weight and cost of the vehicles and their constituent subsystems such as optical imagers, radars, and radio links. The system can include a large number of lower cost, mass, and altitude vehicles, enabling revisit times substantially shorter than previous satellite systems. The vehicles spend their orbit at low altitude, high atmospheric density conditions that have heretofore been virtually impossible to consider for stable orbits. Short revisit times at low altitudes enable near-real time imaging at high resolution and low cost. At such altitudes, the system has no impact on space junk issues of traditional LEO orbits, and is self-cleaning in that space junk or disabled craft will de-orbit.

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.

An example method includes obtaining, by a global navigation satellite system (GNSS) processor of a mobile computing device and based on signals received from GNSS satellites, a stream of I/Q samples; providing, by the GNSS processor and for another processor, the stream of I/Q samples; receiving, by the GNSS processor and from the other processor, aiding data that is determined based on the stream of I/Q samples, wherein the aiding data, that includes: a code phase, a frequency, and a time for a GNSS satellite of the GNSS satellites; and processing, by the GNSS processor and based on the aiding data, the stream of I/Q samples to determine a first fix for the mobile computing device.

An electronic device (such as a transponder or an aircraft that includes the transponder) is described. This electronic device may include: one or more omnidirectional antennas; and one or more integrated circuits (such as one or more radios) that transmit and receive RF signals. During operation, the electronic device may receive, using the one or more omnidirectional antennas, broadcast information associated with a second electronic device (such as a second transponder or a second aircraft that includes the second transponder), where the broadcast information is compatible with a regulation from a government aviation or aviation safety administration (such as the Federal Aviation Administration or the European Union Aviation Safety Agency). Then, the electronic device may determine a track of the second electronic device based at least in part on the broadcast information.

Disclosed is incorporating an IQ stream into a test signal for a receiver in motion, configuring a path for the motion of the receiver during simulation, a period of the simulation, a transmitter constellation to emulate, and a path of at least one IQ stream transmitter. Also generating signals emulating the transmitter constellation and conditioning the stream to be merged with the signals, using distance and relative motion between receiver and transmitter to determine delay and Doppler shift between transmitter and receiver in motion, scheduling sampling of the signal, including interpolation among samples of the stream, based on delay and Doppler shift, and synthesizing a conditioned stream from the interpolation between the samples, taking into account signal level of the stream, in addition to delay and shift, and merging the conditioned signal with the signals emulating the transmitter constellation and supplying the merged signals to the receiver during the test.

Techniques are described for supporting user equipment (UE) positioning in a non-terrestrial network (NTN). To allow calculating a position/location of a UE based on reference signal (RS) measurements to and from one satellite (or a terrestrial base station), a device may be configured to calculate a doppler measurement and a range measurement and report such measurements to be used by a location server to calculate a UE position. An example device may receive a first RS (with the first RS being one of a positioning reference signal (PRS) or a sounding reference signal (SRS)), receive a second RS associated with the first RS, calculate a doppler measurement based on one or both of the first RS or the second RS, and report the doppler measurement. The doppler measurement (such as a measured frequency offset) may be used by a location server to calculate a UE position on the earth surface.