A method is provided for acquiring a signal from a satellite in a global navigation satellite system. The signal includes a pseudorandom code. The method includes, for each time period of a plurality of time periods: generating samples of the signal, segments of the samples of the signal are correlated with a local copy of the pseudorandom code, thereby producing correlation values for the time period. A discrete Fourier transform is performed using, as inputs, the correlation values for the respective time period, thereby producing a frequency representation of the correlation values for the time period. The frequency representations of the correlation values for the plurality of time periods are combined according to a data hypothesis. When a magnitude of the combined frequency representations meets predefined criteria, a frequency corresponding to the magnitude is selected as a tracking frequency for the satellite.

The present disclosure relates to a technical field for airborne navigation and discloses a data acquisition system and method for airborne navigation devices based on unmanned aerial vehicle. The system includes an unmanned aerial vehicle flight control system, a navigation devices test antenna array, a multi-channel signal processing module, a signal acquisition module, an ADS-B transmitting module, a GNSS receiver, a UHF data link receiver, a power module and a ground station. The unmanned aerial vehicle is equipped with corresponding modules to receive signals from ground navigation devices, perform corresponding processing and storage, and transmit data to the ground, at the same time, receive control instructions sent by the ground to complete corresponding monitoring, analysis and inspection.

The present disclosure relates to a technical field for airborne navigation and discloses a data acquisition system and method for airborne navigation devices based on unmanned aerial vehicle. The system includes an unmanned aerial vehicle flight control system, a navigation devices test antenna array, a multi-channel signal processing module, a signal acquisition module, an ADS-B transmitting module, a GNSS receiver, a UHF data link receiver, a power module and a ground station. The unmanned aerial vehicle is equipped with corresponding modules to receive signals from ground navigation devices, perform corresponding processing and storage, and transmit data to the ground, at the same time, receive control instructions sent by the ground to complete corresponding monitoring, analysis and inspection.

A system and method for detecting spoofing of global navigation satellite system (GNSS) signals using a single antenna is provided.

A system and method for detecting spoofing of global navigation satellite system (GNSS) signals using a single antenna is provided.

An apparatus control method includes: controlling a first frequency band receive chain, of an apparatus, to alternate being on and off with a first duty cycle, the first frequency band receive chain being configured to measure satellite signals within a first frequency band; determining one or more performance criteria; and controlling, based on the one or more performance criteria, a second frequency band receive chain, of the apparatus, to alternate being on and off with a second duty cycle, the second frequency band receive chain being configured to measure satellite signals within a second frequency band.

A mobile electronic device including: a movement detection sensor; a positioning module; a processor; and a memory, wherein the processor determines whether the device is moving on the basis of a first tentative determination result obtained by determining whether the device is moving based on a value obtained from the movement detection sensor as well as a second tentative determination result obtained by determining whether the device is moving based on positional information detected by the positioning module, and, upon determining that the device is moving, stores the positional information detected by the positioning module in the memory.

Systems and methods are provided for utilizing a connector to connect an external antenna to a mobile device. GNSS signals, associated with at least two different frequency bands, may be received at the external antenna and the GNSS signals may be transmitted to a connector module of the connector. The connector module may convert analog GNSS signals to generate digital radio frequency (RF) signals. The connector module may encrypt the digital RF signals to generate encrypted digital RF signals. The encrypted digital RF signals may be transmitted from the connector module to the mobile device. A multifrequency GNSS functionality module of the chipset may utilize decrypted digital RF signals to obtain GNSS raw measurements. The multifrequency GNSS functionality module and/or an application executing on the mobile device may utilize the GNSS raw measurements to compute position, velocity, and/or time (PVT).

Systems and methods are provided for utilizing a connector to connect an external antenna to a mobile device. GNSS signals, associated with at least two different frequency bands, may be received at the external antenna and the GNSS signals may be transmitted to a connector module of the connector. The connector module may convert analog GNSS signals to generate digital radio frequency (RF) signals. The connector module may encrypt the digital RF signals to generate encrypted digital RF signals. The encrypted digital RF signals may be transmitted from the connector module to the mobile device. A multifrequency GNSS functionality module of the chipset may utilize decrypted digital RF signals to obtain GNSS raw measurements. The multifrequency GNSS functionality module and/or an application executing on the mobile device may utilize the GNSS raw measurements to compute position, velocity, and/or time (PVT).

A method of inferring the GPS location of a device with a GPS receiver is disclosed. The method includes using signals from two GPS satellites to determine two candidate GPS locations. Geographic information can be used to estimate the probability that the device is at each location. If one of the two candidate GPS locations has a substantially higher probability of being the correct location, that location may be selected as the inferred GPS location. The method may also include making use of additional sensed data that could be provided using sensors onboard the device.