Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections to signals, the Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame, the Doppler corrections applied using Doppler null steering along Null directions. The receiver node is configured to determine a parameter of the signals and an authenticity of the signals based on the parameter.

Abstract: A system may include a transmitter node and a receiver node. Each node may include a communications interface including at least one antenna element and a controller operatively coupled to the communications interface, the controller including one or more processors, wherein the controller of the receiver node has information of own node velocity and own node orientation. The receiver node may be in motion and the transmitter node may be stationary. Each node may be time synchronized to apply Doppler corrections associated with said node's own motions relative to a common reference frame. The common reference frame may be known to the transmitter node and the receiver node prior to the transmitter node transmitting signals to the receiver node and prior to the receiver node receiving the signals from the transmitter node.

Abstract: A communications node of a mobile ad hoc network (MANET) or like multi-node network may receive a preamble and/or header portion associated with a resource allocation message (e.g., as opposed to the full message) transmitted by another network node in motion relative to the receiving node. The receiving node determines a receiver-side Doppler nulling direction (e.g., for offsetting Doppler shift associated with the motion of the transmitting node relative to the receiving node) by adjusting a receiving frequency of the preamble and/or header portion through one or more nulling frequencies, each nulling frequency associated with a nulling direction for offsetting Doppler shift due to relative motion in that direction. Based on the determination of a receiver-side Doppler nulling frequency, the receiving node can determine a velocity and direction of the relative motion between the receiving and transmitting nodes.

Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with a directional antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame. The common reference frame may be known to the receiver or transmitter node prior to the receiver node or transmitter receiving signals from a source.

Abstract: A system may include a transmitter node and a receiver node. Each node may include a communications interface including at least one antenna element and a controller operatively coupled to the communications interface, the controller including one or more processors, wherein the controller has information of own node velocity and own node orientation. Each node of the transmitter node and the receiver node may be in motion relative to each other. Each node may be time synchronized to apply Doppler corrections associated with said node's own motions relative to a common reference frame. The common reference frame may be known to the transmitter node and the receiver node prior to the transmitter node transmitting signals to the receiver node and prior to the receiver node receiving the signals from the transmitter node. The receiver node may be configured to be in a state of reduced emissions.

Abstract: Lossless digital cancelation of internally generated spurious products within a signal receiver system is provided. In embodiments, the receiver system generates reference frequencies corresponding to internal components within the receiver (e.g., mixers, oscillators, clocks, analog-digital converters (ADC)) that introduce spurious products into the digitization of a received RF signal. The receiver system precisely duplicates each introduced spurious product based on the reference frequencies and filters out each corresponding spurious product out of the digitized signal. Individualized canceler circuits for each introduced spurious product adjust the corresponding duplicate spurious products to cancel out the introduced spurious product from the digitized signal, resulting in an output signal free of self-generated interference.

Abstract: A system includes a transmitter node and a receiver node. Each node of the transmitter node and the receiver node are time synchronized to apply Doppler corrections associated with said node’s own motions relative to a stationary common inertial reference frame. The stationary common inertial reference frame is known to the transmitter node and the receiver node prior to the transmitter node transmitting a plurality of packets to the receiver node and prior to the receiver node receiving the plurality of packets from the transmitter node. The plurality of packets each comprise at least a preamble and a body payload. The body payload comprises a plurality of symbols. The plurality of symbols are separated into a plurality of blocks. The plurality of blocks are scanned at separate null directions.

Abstract: A system includes a transmitter node and a receiver node. Each node of the transmitter node and the receiver node are time synchronized to apply Doppler corrections associated with said node's own motions relative to a stationary common inertial reference frame. The stationary common inertial reference frame is known to the transmitter node and the receiver node prior to the transmitter node transmitting a plurality of signals to the receiver node and prior to the receiver node receiving the plurality of signals from the transmitter node. The receiver node performs adaptive digitization of the signals to account for a speed of the platform.

Abstract: A system includes at least a transmitting (Tx) and receiving (Rx) node of a non-terrestrial network (NTN) including one or more non-terrestrial nodes (e.g., operating in earth orbit or extra-terrestrial space). Each node may include a communications interface with antenna elements and a controller, which may include one or more processors and have information of own-node velocity and own-node orientation relative to a common reference frame. Each node may be time synchronized to apply Doppler corrections associated with the node's own motions relative to the common reference frame. Based on the Doppler corrections, each node may determine a relative bearing to the other node. The non-terrestrial node is configured for operation on a non-terrestrial platform (e.g., a satellite in earth orbit), which may be an extra-terrestrial platform operating in spaceflight beyond the earth's atmosphere or in association with a non-Earth solar system object.

Abstract: A Search and Rescue (SAR) system is disclosed. The SAR system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with at least one antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections associated with the receiver or transmitter node’s own motions relative to the common reference frame. For example, the transmitter node may serve as an emergency locator beacon and mark a location of interest, and the receiver node may determine the marked location of interest based at least on the Doppler corrections.

Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an antenna element. A controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections to signals, the Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame, the Doppler corrections applied using Doppler null steering along Null directions. The system may be configured to, via the Doppler null steering, at least one of: track an expendable asset of the system relative to a target; discover a rendezvous node; or identify at least one of a network relay node or a relay location for a network relay node.

Abstract: A system is disclosed. The system may be a directional communications network (e.g., MANET) including at least a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an omnidirectional antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame known to the receiver or transmitter node prior to the receiver or transmitter node receiving signals from a source. The receiver or transmitter node may be time synchronized to apply Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame. The transmitter and receiver nodes may exchange medium access control (MAC) packets prior to establishing directional communications links, determining bearings to each other via Doppler corrections with respect to the packet exchanges.

Abstract: A node of a multi-node network (e.g., a transmitter (Tx) node or receiver (Rx) node) is disclosed. The node may include a communications interface with antenna elements and a controller. The controller may include one or more processors and have information of own-node velocity and own-node orientation relative to a common reference frame. The node may be time synchronized to apply Doppler corrections associated with the node’s own motions relative to the common reference frame. The node may receive an input sequence via a zero or near-zero Doppler path from a source node, the input sequence one of a set possible correlation sequence uniquely identifying the source node. The controller includes a correlator with sub-correlator blocks for breaking the input sequence into a set of N sub-sequences. Based on sequence processing by the sub-correlators, the correlator outputs the decoded input sequence and associated delay metrics.

Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections to signals, the Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame, the Doppler corrections applied using Doppler null steering along Null directions. The receiver node is configured to determine a bearing angle based on the signals based on Doppler null steering; and to determine a range based on two-way time-of-flight based ranging signals.

Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an antenna element. A controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections to signals, the Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame, the Doppler corrections applied using Doppler null steering along Null directions. The system may be configured to, via the Doppler null steering, flood a communication data packet to a destination node based on a spatial awareness. The system may limit the flooding to only be towards the destination node and/or for a maximum number of hops.

Abstract: A system includes a transmitter node and a receiver node. Each node of the transmitter node and the receiver node include a communications interface and a controller operatively coupled to the communications interface. The controller includes one or more processors. Each node of the transmitter node and the receiver node are in motion relative to each other and to a common reference frame. Each node of the transmitter node and the receiver node are time synchronized to apply Doppler corrections associated with said node's own motions relative to the common reference frame. The receiver node is configured to determine a bearing and a range each between the receiver node and the transmitter node. The receiver node is automatically maintained within a formation relative to the transmitter node based on the bearing and range in the station keeping mode.

Abstract: A system is disclosed. The system may include a receiver or transmitter node. The receiver or transmitter node may include a communications interface with an antenna element and a controller. The controller may include one or more processors and have information of own node velocity and own node orientation relative to a common reference frame. The receiver or transmitter node may be time synchronized to apply Doppler corrections to signals, the Doppler corrections associated with the receiver or transmitter node's own motions relative to the common reference frame, the Doppler corrections applied using Doppler null steering along Null directions. The receiver node may comprise a correlator configured to process the signals which are based on the Doppler null steering.

Abstract: A system may include a mobile ad-hoc network (MANET) including nodes. The nodes may include beacon-based clusterhead (BB-CH) nodes and members. Each of the nodes may be configured to transmit communication data packets and transmit beacons. Each of the nodes may have passive spatial awareness. For each of at least some of the BB-CH nodes having members, a BB-CH node may be configured to compile spatial awareness information of all members of the BB-CH node. The compiled spatial awareness information may include a BB-CH node identification, position-location information (PLI) of the BB-CH node, a quantity of the members, and a member list with PLI. For each of the at least some of the BB-CH nodes, the BB-CH node may be configured to broadcast, via efficient flooding, some or all of the compiled spatial awareness information to every connected node.

Abstract: A system and method for frequency offset determination in a MANET via Doppler nulling techniques is disclosed. In embodiments, a receiving (Rx) node of the network monitors a transmitting (Tx) node of the network, which scans through a range or set of Doppler nulling angles adjusting its transmitting frequency to resolve Doppler frequency offset at each angle, the Doppler frequency shift resulting from the motion of the Tx node relative to the Rx node. The Rx node detects the net frequency shift at each nulling direction and can thereby determine frequency shift points (FSP) indicative of the relative velocity vector between the Tx and Rx nodes. If the set of Doppler nulling angles is known to it, the Rx node can determine frequency shift profiles based on the FSPs, and derive therefrom the relative velocity and angular direction of motion between the Tx and Rx nodes.

Abstract: A system may include a transmitter node and a receiver node. Each node may include a communications interface including at least one antenna element and a controller operatively coupled to the communications interface, the controller including one or more processors. Each node may be time synchronized to apply Doppler corrections to said node's own motions relative to a stationary common inertial reference frame. The stationary common inertial reference frame may be known to the transmitter node and the receiver node prior to the transmitter node transmitting signals to the receiver node and prior to the receiver node receiving the signals from the transmitter node.