A method, apparatus and computer program product are provided to correct a predicted value of the position of a navigation satellite and/or a clock offset of a clock of the navigation satellite. In the context of a method implemented by a client computing device, a prediction is received, from a serving computing device, that includes at least one predicted value for the position of the navigation satellite at one or more points in time within a prediction interval. The method also determines, with the client computing device, such as an Internet of Things device, at least one error component and, based thereupon, corrects the prediction received from the serving computing device by correction at least one predicted value for one or more of: (i) the position of the navigation satellite or (ii) the clock offset for the clock of the navigation satellite.

An anti-jamming time synchronization method and apparatus for maintaining time synchronization between a global positioning system (GPS) and a satellite-based augmentation system (SBAS) are provided. The anti-jamming time synchronization method includes receiving a GPS signal from a GPS satellite using an omnidirectional antenna, receiving an SBAS signal from an SBAS satellite using a directional antenna, calculating measurement values of the GPS signal and the SBAS signal, decoding a GPS message of the GPS signal and an SBAS message of the SBAS signal, when the measurement values are values within a normal range, synchronizing time with GPS time based on a measurement value of the GPS signal and the GPS message, and when the measurement values are values beyond the normal range, synchronizing time with the GPS time based on a measurement value of the SBAS signal and the SBAS message.

A method and system for operating an ad hoc communication network under suboptimal commercial global navigation satellite system (GNSS) conditions and a loss of a base station communication link is disclosed. The method includes configuring the ad hoc communication network to operation in in-band or out-of-band mode, allowing device-to-device D2D communication. The method further includes configuring the ad hoc communication system to operate in overlay mode, sharing communication resources between network-controlled resources and D2D resources. The method further includes configuring the D2D resources with a base station precedent to the loss of the base station communication link and enabling the ad hoc communication network to operate in frequency hopping mode. The method further includes disabling physical sidelink control channel synchronization and/or resource management within the ad hoc communication network. In some embodiments of the method, and configuring the ad hoc communication network to include at least one nonstandard-GNSS time-synchronization method.

Aspects of the subject disclosure may include, for example, a positioning system for use with a corresponding one of a plurality of UAVs, the positioning system operable to receive at least one Low Bit Rate (LBR) signal that includes satellite location data from at least one satellite via a receiver of the UAV. Current location data is generated based on the at least one LBR signal. A global positioning system (GPS) signal is generated based on the current location data for transmission, via a transmitter of the UAV, for reception by a GPS receiver. Other embodiments are disclosed.

Satellite relaying for geolocation and mitigation of GNSS denial are provided, where a method comprises: receiving, by a processing device from a communication satellite along a communication path, a message initiated at a transmission time by a transmitting device, the communication path having a target device with an unknown distance to the communication satellite; determining, by the device, a reception time upon receiving the message; determining, by the device, a time of travel of the message associated with only traversal of a portion of the communication that is path between the communication satellite and the target device based on a difference between the transmission time and the reception time; calculating, by the device, a distance between the communication satellite and the target device based on the time of travel; and performing, by the device, one or more actions based on the distance between the communication satellite and the target device.

A system and a method are disclosed for detecting a spurious signal in a Global Navigation Satellite System (GNSS) receiver. A detector of the GNSS receiver determines a first sequence of known bits or known-bit transitions of a space vehicle (SV) signal of a target SV. A second sequence is determined based on a coherent sum of the SV signal being tracked by the GNSS receiver. A first reliability sequence may be associated with the first sequence, and a second reliability sequence that may be associated with the second sequence. A correlation statistic of the first sequence is determined based on the second sequence. Whether the first SV signal is a spurious signal is determined based on a comparison of the correlation statistic to a threshold value.

The embodiments described herein provide ranging capabilities in RF-opaque environments, such as a jungle, that preclude the use of Global Positioning System (GPS) and/or laser ranging systems, utilizing transponders and GPS receivers located on aerial vehicles. The aerial vehicles operate above the RF-opaque environment, and communicate with a ranging device within the RF-opaque environment on frequencies that propagate in the RF-opaque environment. The ranging device transmits RF signals to the transponders, which are received by the transponders and sent back to the ranging device. The aerial vehicles also provide their coordinates to the ranging device using their GPS receivers. The ranging device uses information about the transmitted and received RF signals and the GPS coordinates of the aerial vehicles to calculate a distance to a property line from the ranging device, and/or to calculate a coordinate location of the ranging device.

Disclosed are techniques for positioning. A receiver measures a time of arrival (ToA) of a positioning reference signal (PRS) transmission of a first PRS sequence transmitted by a first transmitter, measures a ToA of a PRS transmission of a second PRS sequence transmitted by a second transmitter, and determines an observed time difference of arrival (OTDOA) as a difference between the ToA of the PRS transmission of the first PRS sequence and the ToA of the PRS transmission of the second PRS sequence, wherein the OTDOA is less than half a maximum differential delay expected between the PRS transmission of the first PRS sequence and the PRS transmission of the second PRS sequence, and wherein a repetition duration of the first PRS sequence and the second PRS sequence is greater than 10 milliseconds (ms) and at least twice the maximum differential delay.

According to one or more of the embodiments herein, systems and techniques for satellite relaying for geolocation and mitigation of Global Navigation Satellite System (GNSS) denial are provided. In one embodiment, a method comprises: receiving, at a processing device from a communication satellite along a communication path, a message initiated by a transmitting device and indicating a transmission time, the communication path having a target device with an unknown distance to the communication satellite; determining a reception time upon receiving the message, (the processing device and the transmitting device have synchronized clocks); determining a time difference between the transmission time and the reception time; calculating a distance between the communication satellite and the target device based on a portion of the determined time difference associated with only traversal of a portion of the communication path between the communication satellite and the target device; and performing action(s) based on the distance.

The embodiments described herein provide ranging capabilities in RF-opaque environments, such as a jungle, that preclude the use of Global Positioning System (GPS) and/or laser ranging systems, utilizing transponders and GPS receivers located on aerial vehicles. The aerial vehicles operate above the RF-opaque environment, and communicate with a ranging device within the RF-opaque environment on frequencies that propagate in the RF-opaque environment. The ranging device transmits RF signals to the transponders, which are received by the transponders and sent back to the ranging device. The aerial vehicles also provide their coordinates to the ranging device using their GPS receivers. The ranging device uses information about the transmitted and received RF signals and the GPS coordinates of the aerial vehicles to calculate a distance to a property line from the ranging device, and/or to calculate a coordinate location of the ranging device.