Abstract: A high-frequency beyond line of sight ad-hoc communication system is disclosed. In embodiments, the system includes an originating node. The originating node is configured to transmit a transmission. In, the system includes a destination node. The destination node is configured to receive the transmission using one or more antennas. In, the system includes one or more relay nodes, which are configured to relay the transmission from the operating mode to the destination mode in a time diverse manner. The relay nodes further comprise a controller, configured to facilitate high-frequency beyond line of sight communication between the originating node and the destination node, wherein the transmission is carried in accordance with a TDMA based waveform that supports frames and time slots. In embodiments, the one or more relay nodes are further configured to relay the transmission from the originating mode to the destination mode in a frequency diverse manner.

Abstract: A high-frequency beyond line of sight ad-hoc communication system is disclosed. In embodiments, the system includes an originating node. The originating node is configured to transmit a transmission. In, the system includes a destination node. The destination node is configured to receive the transmission using one or more antennas. In, the system includes one or more relay nodes, which are configured to relay the transmission from the operating mode to the destination mode in a time diverse manner. The relay nodes further comprise a controller, configured to facilitate high-frequency beyond line of sight communication between the originating node and the destination node, wherein the transmission is carried in accordance with a TDMA based waveform that supports frames and time slots. In embodiments, the one or more relay nodes are further configured to relay the transmission from the originating mode to the destination mode in a frequency diverse manner.

Abstract: A system and method for HF positioning characterizes the undulations of the ionosphere in real-time to determine the refraction altitude of a specific HF frequency at a specific time of day at a specific position. The system accounts for the seasonal (summer, winter) and daily (daylight, night, grey-line transition) variations of the ionosphere determining a highly accurate timing error relative to a timing reference. The system employs a novel approach that is capable of passively and accurately determining a position anywhere in the world without use of a GNSS signal receiving known-time transmissions of narrow band HF timing signals refracted via ionospheric skywave.

Abstract: High frequency (HF) communication devices and methods capable of supporting HF tactical communications are disclosed. A communication device may include a time source configured to provide timing information for the communication device, where the timing information is synchronized with other communication devices participating in the same network the communication device is configured to participate in. The communication device may also include one or more processors in communication with the time source. The one or more processors may be configured to facilitate beyond line of sight reflective communications between the communication device and another communication device participating in the same network, wherein the beyond line of sight reflective communications are carried out in a time synchronized manner and in accordance with a time division multiple access (TDMA) based waveform that supports time slots.

Abstract: A communication network includes and a communication method uses a communication node configured to use a time division multiple access protocol to allow communication in the network. The time division multiple access protocol is configured to allocate time slots. The communication node includes a main transceiver and an auxiliary transceiver. The communication node is configured to listen for a synchronization signal using the main transceiver during a first window and to listen for a synchronization signal during a second window using the auxiliary transceiver.

Abstract: Timing interrogation methods and communication devices utilizing such timing interrogation methods are disclosed. The timing interrogation method may include: sending a round-trip timing interrogation preamble from a first radio node to a second radio node via the ionosphere; receiving a round-trip timing response at the first radio node via the ionosphere from the second radio node; receiving a time of arrival record at the first radio node via the ionosphere from the second radio node, wherein the time of arrival record indicates the time of arrival of the round-trip timing interrogation preamble at the second radio node according to timing information maintained by the second radio node; calculating timing information based on the time of arrival record and a propagation time of the round-trip timing interrogation preamble and the round-trip timing response; and adjusting time information maintained by the first radio node according to the calculated timing information.

Abstract: A communication system periodically changes the carrier wave frequency or phase such that a signal traveling a reflected path no longer destructively interferes with a signal traveling a direct line-of-sight path. The communication system negotiates a periodic frequency or phase shift with a receiver, and then shifts the frequency or phase according to the negotiated schedule to maintain continuous communication.

Abstract: A system and method for ad-hoc beyond line of sight high frequency (HF) radio frequency communication is disclosed. Embodiments of the present invention may augment the HF waveform incorporated with Advanced automatic link establishment (A2LE) to determine relay-hop paths between a plurality of HF nodes. Systems herein may setup and teardown bi-directional one hop HF communication sessions between two HF nodes having RF connectivity directly as well as through an intermediary relay node. Additionally, the setup and teardown may include bi-directional relay hop HF communication sessions between two HF nodes through multiple intermediary relay nodes. In performing the bi-directional relay hop HF communication sessions, systems herein may select a relay node, perform automatic link monitoring and link re-establishment, support message store and forward, and route HF communication along a path around potential barriers to communication (e.g., nuclear scintillation, solar flares, and coronal mass events).

Abstract: The present invention includes providing a multidirectional antenna unit including a plurality of directional antenna elements configured to spatially segment an operational theatre into a plurality of segmented regions, receiving radio frequency signals via the plurality of directional antenna elements from the plurality of segmented region, identifying a directional antenna element having the highest signal-to-jamming ratio, and connecting the directional antenna element having the highest signal-to-jamming ratio to a multifunction information distribution system terminal.

Abstract: An interference cancellation system supports a dynamic operating range from maximum interfering signal level to the on-channel noise floor. The system uses a novel combination of analog and digital processing effectively cancelling 1) high-level interfering signal components, 2) low-level interfering noise, and 3) distortion components. The system employs an interrelated combination of cross-domain analog and digital processing techniques to defeat the inherent dynamic range limitations existing in either individual domain.

Abstract: Present novel and non-trivial apparatus and method for generating low latency position information from position signals transmitted in a narrow bandwidth channel of a radio frequency are disclosed. An aircraft (i.e., ownship) and each target (e.g., aircraft) of a time-division multiple access (“TDMA”) network receives its respective position derived from its individual source such as a satellite navigation system. A processing module of a communication device installed in ownship and each target generate position signals, and during the allocated time slots of an interface protocol, exchange position information with the others in the network over a narrow bandwidth channel (e.g., bandwidths of 25 KHz or less) of a radio frequency in the VHF range or lower UHF range. The interface protocol may also be comprised of a voice contention time slot for the transmission of messages and an order wire for the administration of the network.

Abstract: A system for improving jamming resistance comprising a first node suitable for transmitting a coded packet and a second node suitable for receiving the coded packet. The first node generates a plurality of coded preamble packets and transmits the plurality of coded preamble packets to the second node on a plurality of frequency channels, the second node receives the plurality of coded preamble packets, determines a relative strength for each of the plurality of frequency channels based on a frequency channel condition determined from the transmission of the plurality of coded preamble packets and transmits a frequency channel response to the first node.

Abstract: Present novel and non-trivial apparatus and method for generating low latency position information from position signals transmitted in a narrow bandwidth channel of a radio frequency are disclosed. An aircraft (i.e., ownship) and each target (e.g., aircraft) of a time-division multiple access (“TDMA”) network receives its respective position derived from its individual source such as a satellite navigation system. A processing module of a communication device installed in ownship and each target generate position signals, and during the allocated time slots of an interface protocol, exchange position information with the others in the network over a narrow bandwidth channel (e.g., bandwidths of 25 KHz or less) of a radio frequency in the VHF range or lower UHF range. The interface protocol may also be comprised of a voice contention time slot for the transmission of messages and an order wire for the administration of the network.

Abstract: A system may include a receiver having a number of reception channels spread across an instantaneous radio frequency bandwidth, each one of the reception channels for receiving a different radio frequency within the instantaneous radio frequency bandwidth. The system may also include control programming for positioning the receiver on one of a number of synchronization frequencies transmitting a synchronization preamble, where a number of reception channels is less than a number of synchronization frequencies, and a probability of not receiving one or more of the synchronization frequencies is smaller than a required message error rate for receiving the plurality of synchronization frequencies.

Abstract: A node for communicating with multiple ad hoc communication networks includes a first antenna configured to communicate in a first frequency band associated with a first ad hoc communication network and a second antenna configured to communicate in a second frequency band associated with a second ad hoc communication network. A transceiver is coupled to the first antenna and the second antenna. The transceiver is configured to transmit and receive messages. A control circuit is coupled to the transceiver and is configured to implement an access protocol having a time slot section. The access protocol is configured to switch communications in the time slot section between the first frequency band and the second frequency band.

Abstract: A device reconfigurable to support communication using different communication technologies is provided. The device includes, but is not limited to, a plurality of communication processing modules and a switching interface. The switching interface couples to the plurality of communication processing modules. An instruction set is written into the device to select one or more communication processing module of the plurality of communication processing modules to connect using the switching interface. One or more of the communication processing modules may be programmable. The instruction set may include programmable parameters and/or programming instructions for the one or more programmable communication processing modules. As a result, the device is reprogrammable and reconfigurable to process different communication signals while utilizing less power than conventional designs.

Abstract: A method for sharing thermal load between nodes in a communication network includes monitoring the thermal load of a first node in the communication network. The first node is an advantaged node. When the thermal load of the first node is a predetermined value, a second node is selected as an advantaged node. A notification message is transmitted to the plurality of nodes in the communication network identifying the second node as an advantaged node for at least a subset of message traffic of the first node.

Abstract: A power supply for a communications device, including a controllable regulator that varies power drawn from a power input according to communications requirements of the communications device. The controllable regulator increases power drawn from the power input immediately before an increase of power is required by the communications device when a magnitude of a rate of change of required power exceeds a predetermined level. An active filter is connected to an output of the controllable regulator. The active filter is controlled to variably divert power that is output from the controllable regulator in excess of what is required by the communications device, wherein electromagnetic emissions resulting from the rate of change of power are reduced.

Abstract: A system for pre-processing transmission sequences in a jammed environment. System a transmitter suitable for transmitting the synchronization preamble further comprising a pseudo noise generator suitable for running a non predictable pseudo random algorithm. Pseudo random algorithm is suitable for generating a codeword operable as a pointer indexed into a table of gold sequences. Pointer is suitable for selecting a pseudo random selection of gold sequences from the table of gold sequences. Pseudo random selection of gold sequences forms a synchronization preamble. Gold sequences are concatenated together to form the synchronization preamble. System further comprises a receiver configured to receive the transmitted synchronization preamble further comprising of a decryption key suitable for decrypting received synchronization preamble.

Abstract: A method for reallocating bandwidth includes assigning a node to a position message slot, running an allocation algorithm, generating a table based on the allocation algorithm, selecting a row of the table, aligning a value of the row with a node identifier; and assigning the node to a mini-slot within the position message slot based on the aligning of the value of the row and the node identifier.