Bae Systems Information and Electronic Systems Integration Inc.

Raytheon Company

David J Couto

Prabahan Basu

William Dugald Watson, Jr

Jonathan P Beaudeau

Harry B Marr

Michael J Shea

Apurva N Mody

Jeffery Jay Logan

John A Tranquilli, Jr

Scott A Kuzdeba

Chad E Patterson

Denis Garagic

Amit Bhatia

Timothy M Schaefer

An adaptive filter protocol stored on a non-transitory computer readable medium that is operatively in communication with a processor of a platform. The adaptive filter protocol includes a first processing loop that is operatively in communication with at least one receiving device of the platform for receiving at least one input signal. The adaptive filter protocol also includes a second processing loop that is operatively in communication with the first processing loop and has a deterministic gradient descent optimization logic and an interpolation logic. When the at least one receiving device receives the at least one input signal, the adaptive filter protocol enables the processor to generate a refined match filter parameters that substantially correlates with the initial parameters of the at least one input signal upon completing a plurality of refining cycles of the second processing loop.

Interpolated deterministic gradient adaptive filter

The discriminability of an RF fingerprint is increased by 'abstracting,' 'enhancing,' and &#x201c;reconstructing&#x201d; a digital signal before it is transmitted, where the abstraction is a reversible nonlinear compression, the enhancement is a modification of the abstracted data, and the reconstruction is a mapping-back of the abstraction. During a training phase, for each individual RF transmitter, RF fingerprints are analyzed and candidate enhancements are modified until a successful enhancement is identified that provides satisfactory discriminability improvement with minimal signal degradation. The successful enhancement is implemented in the RF transmitter, and the RF fingerprint is communicated to receivers for subsequent detection and verification. Reinforcement learning can direct modifications to the candidate enhancements. The abstraction can implement a deep generative model such as an auto-encoder. A covert data enhancement can encode covert data onto the RF fingerprint, whereby the covert data is transmitted covertly to a receiver.

RF fingerprint enhancement by manipulation of an abstracted digital signal

A multi-user system to simultaneously perform operations such as communication, RADAR, Light Detection and Ranging (LIDAR) and Relative Navigation (RELNAV). The techniques according to an embodiment includes generating a Fourier based orthogonal chirp sequence of length P, a prime number greater than the number of users targeted for communication. The orthogonal chirp sequence is based on an identifier, in the range of one to P&#x2212;1, associated with one of the targeted users. The method further includes using the orthogonal chirp sequence to generate a spread user signal based on a message directed to the one targeted users. The method further includes generating a sequence of training pulses for insertion into the spread user signal to facilitate reception of the signal. The method further includes transmitting and receiving a reflection of the spread user signal from one of the targeted users, the reflection used to detect and range the user.

Orthogonal chirps for Radar, relative navigation and ranging, Light Detection and Ranging, and communications fungibility

An electronic transmitter includes: a modulator to phase modulate a carrier signal with a baseband signal using a phase modulation sequence; and an emitter to emit the phase modulated signal. The phase modulated signal has poor autocorrelation, has a corresponding mismatched filter based on the phase modulation sequence, and is configured to demodulate into the baseband signal through poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a sensing apparatus, where the emitter emits the phase modulated signal at a target and the emitted signal reflects off the target. The sensing apparatus includes a receiver that has a collector to collect the reflected signal, and a demodulator to demodulate the collected signal into the baseband signal through the poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a communication system, where the emitter emits the phase modulated signal to an intended recipient.

Techniques for phase modulated signals having poor autocorrelation

An electronic transmitter includes: a generator circuit to generate a baseband signal; a modulator circuit to modulate a carrier signal with the baseband signal; an emitter to emit the modulated signal at an intended recipient; and a distortion circuit to apply a final distortion to the baseband signal or the modulated signal. The final distortion is optimized to minimize the ability of unintended recipients to localize the emitter using correlation-based techniques, and to minimize any degradation to the data rate of the emitted signal at the intended recipient. In some cases, the transmitter is part of an electronic communication system that also includes a receiver at the intended recipient. The receiver is aware of the final distortion and includes a collector to collect the emitted signal, and a demodulator circuit to demodulate the collected signal using the final distortion to recover the baseband signal.

Distortion-based techniques for communications localization denial

An asymmetric power amplifier includes: an input port for receiving a multi carrier signal including a first subcarrier and a second subcarrier; a first tunable analog filter for filtering the received multi carrier signal into a first signal of the first subcarrier; a second tunable analog filter for filtering the received multi carrier signal into a second signal of the second subcarrier; an amplifier for amplifying the first signal of the first subcarrier; a power amplifier for power amplifying the second signal of the second subcarrier; a combiner for power combining the amplified first signal and the amplified second signal to form a power combined multi carrier signal; and an output port for outputting the power combined multi carrier signal to be transmitted by a transmitter.

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Pepperell, MA, United States of America

David J Couto