Abstract: Systems, methods, and apparatus for denoising signals are disclosed. In one aspect, an apparatus is provided. The apparatus may comprise a first denoiser configured to receive an input signal and to generate a denoised signal and a signal reverser configured to receive the input signal and to generate a time reversed signal. The apparatus may also include a second denoiser configured to receive the time reversed signal and to generate a denoised time reversed signal. Further, the apparatus may include a signal combiner configured to combine the denoised signal with the denoised time reversed signal to generate an output signal.

Abstract: Systems, methods, and apparatus for processing signals using a sensor arrays are disclosed. In one aspect, an apparatus comprising a sensor array and a computing device is provided. The computing device may comprise one or more processors configured to generate a data matrix based on one or more signals received at each of the plurality of sensor and to determine a covariance matrix based on the data matrix. The one or more processors may also be configured to decompose the covariance matrix into a matrix of eigenvalues and a matrix of eigenvectors and to determine a projected data matrix based on applying the data matrix to the eigenvector matrix. Further, the one or more processors may be configured to determine a denoised projected data matrix based on denoising the projected data matrix and to determine a denoised data matrix based on the denoised projected data matrix.

Abstract: An automatic aircraft positioning system includes a first aircraft including one more fiducials, and a second aircraft including a positioning radar, control devices that are configured to control operation of the second aircraft, and a control unit in communication with the positioning radar and the control devices. The positioning radar is configured to transmit a radar transmit signal. The one or more fiducials are configured to receive the radar transmit signal and output one or more return signals in response to the radar transmit signal. The positioning radar is configured to receive the one or more return signals and determine a position and orientation of the second aircraft relative to the first aircraft, or vice versa, from the one or more return signals. The control unit is configured to automatically control the second aircraft in relation to the first aircraft during an automatic positioning mode.

Abstract: An automatic aircraft positioning system includes a first aircraft including one more fiducials, and a second aircraft including a positioning radar, control devices that are configured to control operation of the second aircraft, and a control unit in communication with the positioning radar and the control devices. The positioning radar is configured to transmit a radar transmit signal. The one or more fiducials are configured to receive the radar transmit signal and output one or more return signals in response to the radar transmit signal. The positioning radar is configured to receive the one or more return signals and determine a position and orientation of the second aircraft relative to the first aircraft, or vice versa, from the one or more return signals. The control unit is configured to automatically control the second aircraft in relation to the first aircraft during an automatic positioning mode.

Abstract: A radar system includes a transmitter for transmitting a radio frequency (RF) signal or a radar signal and a plurality of receivers. Each receiver receives a plurality of reflected signals created by a plurality of targets reflecting the RF signal or radar signal. The reflected signals include background noise and each of the receivers are separated by a predetermined distance. The radar system also includes a multiple input de-noiser configured to de-noise input signals from the plurality of receivers and to determine a time difference of arrival of the reflected signals between the plurality of receivers. A detection and angular resolution module is configured to determine an angular resolution between the plurality of targets using the time difference of arrival of the reflected signals between the plurality of receivers.

Abstract: A radar system including a transmit antenna for transmitting a radio frequency (RF) signal or a radar signal and a receive antenna for receiving a plurality of reflected signals created by a plurality of targets reflecting the RF signal or radar signal. The reflected signals include noise. The radar system also includes an analog-to-digital converter (ADC) that digitizes or samples the reflected signals to provide a digitized or sampled noisy input signal. The radar system further includes a reservoir computer that receives the noisy input signal. The reservoir computer includes a time-varying reservoir and is configured to de-noise the noisy input signal and provide a range measurement for each of the plurality of targets.

Abstract: A method for removing an extracted RF signal to examine a spectrum of at least one other RF signal includes receiving a mixture signal by an ADC. The mixture signal includes a plurality of separate signals from different signal sources. The mixture signal is digitized by the ADC. A first digitized signal and a second digitized signal are generated that are the same. The first digitized signal is delayed a predetermined time delay and the second digitized signal is processed in a neuromorphic signal processor to extract an extracted signal. The predetermined time delay corresponds to a delay embedding in the neuromorphic signal processor. A phase delay and amplitude of the extracted signal is adjusted based on a phase delay and amplitude of the first digitized signal. An adjusted extracted signal is cancelled from the first digitized signal to provide an input examination signal for examination.

Abstract: In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.

Abstract: A radar system includes a transmitter for transmitting a radio frequency (RF) signal or a radar signal and a plurality of receivers. Each receiver receives a plurality of reflected signals created by a plurality of targets reflecting the RF signal or radar signal. The reflected signals include background noise and each of the receivers are separated by a predetermined distance. The radar system also includes a multiple input de-noiser configured to de-noise input signals from the plurality of receivers and to determine a time difference of arrival of the reflected signals between the plurality of receivers. A detection and angular resolution module is configured to determine an angular resolution between the plurality of targets using the time difference of arrival of the reflected signals between the plurality of receivers.

Abstract: In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.

Abstract: A signal receiver includes receive circuitry. The signal receiver further includes a processor coupled to the receive circuitry and configured to receive, from a filter, a stream of samples including a first set of samples. A data rate of an input of the filter may correspond to a data rate of an output of the filter. The first set of samples includes multiple samples. The processor is further configured to perform a detection operation on the first set of samples. The processor is further configured to detect a signal emitter based on the detection operation.

Abstract: In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.

Abstract: A radar system including a transmit antenna for transmitting a radio frequency (RF) signal or a radar signal and a receive antenna for receiving a plurality of reflected signals created by a plurality of targets reflecting the RF signal or radar signal. The reflected signals include noise. The radar system also includes an analog-to-digital converter (ADC) that digitizes or samples the reflected signals to provide a digitized or sampled noisy input signal. The radar system further includes a reservoir computer that receives the noisy input signal. The reservoir computer includes a time-varying reservoir and is configured to de-noise the noisy input signal and provide a range measurement for each of the plurality of targets.

Abstract: A method for removing an extracted RF signal to examine a spectrum of at least one other RF signal includes receiving a mixture signal by an ADC. The mixture signal includes a plurality of separate signals from different signal sources. The mixture signal is digitized by the ADC. A first digitized signal and a second digitized signal are generated that are the same. The first digitized signal is delayed a predetermined time delay and the second digitized signal is processed in a neuromorphic signal processor to extract an extracted signal. The predetermined time delay corresponds to a delay embedding in the neuromorphic signal processor. A phase delay and amplitude of the extracted signal is adjusted based on a phase delay and amplitude of the first digitized signal. An adjusted extracted signal is cancelled from the first digitized signal to provide an input examination signal for examination.

Abstract: A signal receiver includes receive circuitry. The signal receiver further includes a processor coupled to the receive circuitry and configured to receive, from a filter, a stream of samples including a first set of samples. A data rate of an input of the filter may correspond to a data rate of an output of the filter. The first set of samples includes multiple samples. The processor is further configured to perform a detection operation on the first set of samples. The processor is further configured to detect a signal emitter based on the detection operation.

Abstract: A multi-beam frequency-modulated continuous wave (FMCW) radar system designed for short range (<20 km) operation in a high-density threat environment against highly maneuverable threats. The multi-beam FMCW system is capable of providing continuous updates, both search and track, for an entire hemisphere against short-range targets. The multi-beam aspect is used to cover the entire field of regard, whereas the FMCW aspect is used to achieve resolution at a significantly reduced computational effort.

Abstract: A multi-beam frequency-modulated continuous wave (FMCW) radar system designed for short range (<20 km) operation in a high-density threat environment against highly maneuverable threats. The multi-beam FMCW system is capable of providing continuous updates, both search and track, for an entire hemisphere against short-range targets. The multi-beam aspect is used to cover the entire field of regard, whereas the FMCW aspect is used to achieve resolution at a significantly reduced computational effort.

Abstract: A method and apparatus for analyzing movement of objects in a border area. Information about the movement of the objects in the border area is identified from sensor data. The information about the movement of the objects in the border area is compared with movement information for the border area to form a comparison. An alert is generated when the comparison indicates that an object of interest in the objects is present.

Abstract: In an antenna array, signals may be manipulated to increase coherency at certain locations (beamfocusing) and reduce or cancel the signals at other locations (nulling). This is accomplished by multiplying the signals received or transmitted by the set of antennas by a weight vector that is generated by determining a covariance matrix based on a vector representing signals at the set of antennas, vectors representing the desired beamfocusing and nulling locations, and a desired nulling depth.

Abstract: A method for ground surveillance radar performance analysis is disclosed. A vector of point data items indexed by time offset, and comprising a point probability of detection is received. A plurality of initial azimuths of a simulated radar signal of the radar tower is determined based on the radar field-of-regard. A plurality of initial azimuth segment probabilities of detection are calculated for each of the initial azimuths respectively based on the vector of point data items and the initial azimuths, and a segment probability of detection is determined based on the initial azimuth segment probabilities of detection.