Abstract: For global navigation satellite system (GNSS)-independent operation of auxiliary PNT systems, one or more ground stations of the auxiliary system have access to a non-GNSS source of precision timing. That source and known locations of the ground stations may be used to derive timing corrections to account for imperfect clocks in the satellites for non-purpose-built satellite systems being used for PNT. Crosslinks between satellites and/or propagation of timing correction through other ground stations are used to better control the timing and resulting precession of PNT in the PNT auxiliary system. The timing correction may be provided as a service to end users, other constellations, and/or other satellite operators.

Abstract: For validation of wireless signals, a wireless receiver receives a validation signal that includes information from a target signal. By using digital signature, message authentication code (MAC), and/or hashing, the validation signal is verified to be from a trusted source. By comparing the information from the verified validation signal with the target signal, the target signal is confirmed to be genuine or not a spoofing signal. In one approach, the validation signal is provided from a different transmission source than the target signal. In another approach, modulation estimation rather than known modulation is used as the information for the validation signal for comparison with the target signal despite not knowing the spread pattern of the coding. In yet another approach, a one-way function is used to generate a pseudorandom code to spread a first component of the a first signal below the noise floor. The input to the one-way function is a second component sent at a time later than the time.

Abstract: For validation of position, navigation, time (PNT) signals, a hash included in messages with PNT data is used to validate the source of the message without backhaul. Different tags from a hash chain are included in different messages. The receiver is pre-loaded with the root or later trusted hash tag of the chain as created. The hash of any received message may be hashed by the receiver. The result of the hashing will match the pre-loaded or trusted hash tag if the transmitter of the message is a valid source. The PNT data may be validated using a digital signature formed from the PNT data for one or more messages and the hash tag wherein a hash tag of the chain in a subsequently received message is used as the key. The digital signature may be formed from data across multiple messages.

Abstract: Aspects of the disclosure relate to a method for determining a location of a first device. The method comprises receiving, by the first device, at least one first signal from at least one second device. The method further comprises determining, by the first device, estimated first signal properties of at least one first signal. Also, the method comprises generating, by the first device, at least one second signal based on at least a portion of the estimated first signal properties. Further, the method comprises transmitting, by the first device, at least one second signal to at least one third device. In one or more embodiments, estimated second signal properties of at least one second signal are determined by at least one third device. In at least one embodiment, the location of the first device is determined by utilizing at least a portion of the estimated second signal properties.

Abstract: Aspects of the disclosure relate to positioning, navigation, and timing (PNT) satellite beam and data scheduling. In one or more embodiments, a method for determining a location and/or time offset of at least one receiver involves transmitting, by at least one satellite, at least one beam, which is a sweeping beam. In one or more embodiments, each of the beams comprises at least one signal used for positioning, navigation, or timing. The method further comprises varying, by at least one satellite, aspects of at least one signal based on optimization parameters. In at least one embodiment, the optimization parameters comprise a location of a beam footprint of at least one beam. In one or more embodiments, at least one receiver receives at least one signal. In at least one embodiment, the location and/or the time offset of at least one receiver is determined by using at least one signal.

Abstract: For assisted satellite time and location (STL) in low earth orbit (LEO) and/or burst transmission-based STL, assistance is provided. Ephemeris information is provided to receivers of signals from LEO satellites, allowing the receivers to operate better in PNT based on the signals from the LEO satellites. Other information may be used to assist, such as terrestrial-based time and/or location of the receiver. For burst transmissions, the data (e.g., spread code) used for some or all the burst transmission is provided to the receiver, which may then replicate the signal. This replica signal assists in PNT based on the signals from the satellites transmitting the burst signals.

Abstract: For global navigation satellite system (GNSS)-independent operation of auxiliary PNT systems, one or more ground stations of the auxiliary system have access to a non-GNSS source of precision timing. That source and known locations of the ground stations may be used to derive timing corrections to account for imperfect clocks in the satellites for non-purpose-built satellite systems being used for PNT. Crosslinks between satellites and/or propagation of timing correction through other ground stations are used to better control the timing and resulting precession of PNT in the PNT auxiliary system. The timing correction may be provided as a service to end users, other constellations, and/or other satellite operators.

Abstract: For validation of position, navigation, time (PNT) signals, a hash included in messages with PNT data is used to validate the source of the message without backhaul. Different tags from a hash chain are included in different messages. The receiver is pre-loaded with the root or later trusted hash tag of the chain as created. The hash of any received message may be hashed by the receiver. The result of the hashing will match the pre-loaded or trusted hash tag if the transmitter of the message is a valid source. The PNT data may be validated using a digital signature formed from the PNT data for one or more messages and the hash tag wherein a hash tag of the chain in a subsequently received message is used as the key. The digital signature may be formed from data across multiple messages.

Abstract: For validation of position, navigation, time (PNT) signals, a hash included in messages with PNT data is used to validate the source of the message without backhaul. Different tags from a hash chain are included in different messages. The receiver is pre-loaded with the root or later trusted hash tag of the chain as created. The hash of any received message may be hashed by the receiver. The result of the hashing will match the pre-loaded or trusted hash tag if the transmitter of the message is a valid source. The PNT data may be validated using a digital signature formed from the PNT data for one or more messages and the hash tag wherein a hash tag of the chain in a subsequently received message is used as the key. The digital signature may be formed from data across multiple messages.

Abstract: A method and system are disclosed for providing an estimate of a location of a user receiver device. The method involves emitting, from at least one vehicle, at least one spot beam on Earth; and receiving, with the user receiver device, at least one spot beam. The method further involves calculating, with the user receiver device, the estimate of the location of the user receiver device according to the user receiver device's location within at least one spot beam. Each spot beam contains at least one acquisition signal, which may comprise at least one ring channel. Each ring channel comprises a frame count; a space vehicle identification (SVID); a spot beam identification (ID); and/or X, Y, Z coordinates of the vehicle emitting the spot beam relative to an Earth coordinate system. In one or more embodiments, at least one vehicle may be a satellite and/or a pseudolite.

Abstract: A system and methods for resolving integer cycle ambiguity in medium wave carrier radio signals are presented. A satellite signal is received at a receiving location and a measured code phase of the satellite signal is measured. A satellite location estimate of the receiving location is computed based on the measured code phase. Medium wave radio carrier signals from medium wave radio transmitters are received at the receiving location. A number of wavelengths of the medium wave radio carrier signals from the satellite location estimate to each of the medium wave radio transmitters is determined respectively. A carrier phase of each of the medium wave radio carrier signals is measured. An improved position estimate of the receiving location is computed based on the number of wavelengths and the carrier phase of each of the medium wave radio carrier signals, and a location of each of the medium wave radio transmitters.

Abstract: A system, method, and apparatus for secure routing based on a degree of trust are disclosed herein. The disclosed method involves assigning a level of trust to at least one network node, and utilizing the level of trust to determine a degree of security of the network node(s). The level of trust of the network node(s) is related to an amount of certainty of the physical location of the network node(s). The amount of certainty is attained from the network node(s) being located in a known secure location, and/or from verification of the physical location of the network node(s) by using satellite geolocation techniques or by using network ping ranging measurements. The method further involves utilizing the level of trust of the network node(s) to determine a degree of trust of at least one path for routing the data, where the path(s) includes at least one of the network nodes.

Abstract: A system, method, and apparatus for secure routing based on the physical location of routers are disclosed herein. The disclosed method for secure data transmission of at least one data packet through a plurality of network nodes involves defining a source network node, a destination network node, and at least one security constraint, which is based on the physical location of at least one of the network nodes. The method further involves comparing available network nodes with the security constraint(s) to determine which of the available network nodes meet the security constraint(s) and, thus, are qualified network nodes. Additionally, the method involves determining a route comprising at least one of the qualified network nodes to route the data packet(s) through from the source network node to the destination network node. Further, the method involves transmitting the data packet(s) through the route of the qualified network node(s).

Abstract: A system and method for verifying and/or geolocating network nodes in attenuated environments for cyber and network security applications are disclosed. The system involves an origination network node, a destination network node, and at least one router network node. The origination network node is configured for transmitting a data packet to the destination network node through at least one router network node. The data packet contains a security signature portion, a routing data portion, and a payload data portion. The security signature portion comprises a listing of at least one network node that the data packet travelled through from the origination network node to the destination network node. In addition, the security signature portion comprises geolocation information, identifier information, and timing information for at least one network node in the listing.

Abstract: A system, method, and apparatus for the authentication of the physical location of a target node are disclosed herein. In one or more embodiments, the authentication of the target node's physical location is achieved by using ping ranging measurements obtained from the amount of time that elapses during ping messages being sent between the target node and at least one trusted node with a known physical location. The physical location of the trusted node(s) is obtained by using satellite geolocation techniques. The accuracy of the ranging measurements may be improved upon by using pre-coordination and/or priority determination of the ping messages being sent between the target node and the trusted node(s). In at least one embodiment, the ping messages are sent by dedicated ping response hardware that is associated with the target node and/or the trusted node(s). In some embodiments, the ping messages include a pseudo random code bit sequence.

Abstract: A system, method, and apparatus for contextual-based virtual data boundaries are disclosed herein. In particular, the present disclosure relates to improvements in access control that work to restrict the accessibility of data based on assigning contextual data thresholds that create a virtual boundary. Specifically, the disclosed method involves assigning at least one threshold to at least one contextual criterion. The method further involves determining whether contextual information from the claimant meets at least one threshold to at least one contextual criterion. Also, the method involves authenticating the claimant, if the contextual information from the claimant meets at least one of the thresholds to at least one contextual criterion. Further, the method involves allowing the claimant access to the data, if the claimant is authenticated.

Abstract: A system and method for verifying and/or geolocating network nodes in a network in attenuated environments for cyber and network security applications are disclosed. The system involves an origination network node, a destination network node, and at least one router network node. The origination network node is configured for transmitting a data packet downstream to the destination network node through at least one router network node. The data packet contains a header portion and a payload data portion. At least one of the network nodes is an enabled network node. The enabled network node(s) is configured to verify any of the network nodes that are located upstream from the enabled network node(s) by analyzing the header portion and/or the payload data portion of the data packet.

Abstract: A system and method for verifying and/or geolocating network nodes in a network in attenuated environments for cyber and network security applications are disclosed. The system involves an origination network node, a destination network node, and at least one router network node. The origination network node is configured for transmitting a data packet downstream to the destination network node through at least one router network node. The data packet contains a header portion and a payload data portion. At least one of the network nodes is an enabled network node. The enabled network node(s) is configured to verify any of the network nodes that are located upstream from the enabled network node(s) by analyzing the header portion and/or the payload data portion of the data packet.

Abstract: A transmission-based authentication system and method to prevent an unauthorized claimant from tracking a signal are disclosed herein. In one or more embodiments, the method involves transmitting, from at least one transmission source, a plurality of authentication signals. The method further involves receiving, from at least one receiving source, a resultant signal that includes at least two of the authentication signals. Further, the method involves authenticating, with at least one authenticator device, at least one claimant by comparing properties of the resultant signal the claimant receives from the receiving source location(s) to expected properties of the resultant signal that the claimant should receive from the receiving source location(s). The properties that are compared are signal power, doppler shift, time of reception, and/or signal modulation. The transmission source(s) is employed in at least one satellite and/or at least one pseudo-satellite.

Abstract: System, methods, and devices for a self-sustaining differential corrections network that employs roving reference devices (RRDs) as reference stations for improving positioning, navigation, and timing (PN&T) solutions for other enabled local roving and/or stationary receiving devices (RDs) are disclosed herein. The disclosed differential correction system enhancement leverages RRDs enabled for a non-global positioning system (non-GPS), secondary PN&T signal to characterize local errors. These local errors are then used by local RDs in combination with a signal to calculate an improved PN&T estimate for the RDs.