摘要:
Embodiments of a system and method are disclosed that exploit the unique higher order statistics of temporally dependent waveforms to detect and enumerate signals in a multi-signal and noise environment. The embodiments use spatial 4th-order cumulants or spatial 2nd-order moments in a Blind Source Separation operation and generalized eigenvalue decomposition to determine unique matrix pencil eigenvalues for a set of unknown signals. Sequential detection in the complex plane of the eigenvalues in associated tracks for successive blocks of sensor data serve as the basis of the detection decision. The embodiments may include a multi-element array and do not require a priori knowledge of the signal environment to detect and enumerate the signals.
摘要:
A transmitted signal's higher order statistics of temporally dependent waveforms are exploited to geolocate low power signals. The geolocation is independent of the characteristics or encoded data of the transmitted waveform. The method uses spatial fourth order cumulants or spatial second order moments in a Blind Source Separation and generalized eigenvalue decomposition to determine unique matrix pencil eigenvalues and eigenvectors. The eigenvectors provide are orthogonal to the steering vector of the transmitted signal save one, which represents the steering vector. This property is used to determine Steering vectors, AoA or geolocation. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source to geolocate the target transmitter. The methods and apparatus for geolocation does not require typical demodulation.
摘要:
A transmitted signal's higher order statistics of temporally dependent waveforms are exploited to geolocate low power signals. The geolocation is independent of the characteristics or encoded data of the transmitted waveform. The method uses spatial fourth order cumulants or spatial second order moments in a Blind Source Separation and generalized eigenvalue decomposition to determine unique matrix pencil eigenvalues and eigenvectors. The eigenvectors provide are orthogonal to the steering vector of the transmitted signal save one, which represents the steering vector. This property is used to determine Steering vectors, AoA or geolocation. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source to geolocate the target transmitter. The methods and apparatus for geolocation does not require typical demodulation.
摘要:
A transmitted signal's higher order statistics of temporally dependent waveforms are exploited to geolocate low power signals. The geolocation is independent of the characteristics or encoded data of the transmitted waveform. The method uses spatial fourth order cumulants or spatial second order moments in a Blind Source Separation and generalized eigenvalue decomposition to determine unique matrix pencil eigenvalues and eigenvectors. The eigenvectors provide are orthogonal to the steering vector of the transmitted signal save one, which represents the steering vector. This property is used to determine Steering vectors, AoA or geolocation. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source to geolocate the target transmitter. The methods and apparatus for geolocation does not require typical demodulation.
摘要:
A receiver exploits unique higher order statistics of temporally dependent waveforms to classify, characterize, identify (fingerprint) and intercept a waveform within the field of view of the receiver. The method uses 4th-order non zero lag auto cumulants of the received waveform and 4th-order non zero lag auto cumulants of known waveforms to classify and characterize the signal. The receiver includes a multi-element array and does not need a priori knowledge of the transmitted signal source obtain a fingerprint.
摘要:
A synthetic aperture radar (SAR) for a moveable platform includes an antenna, a radar transmitter and radar receiver cooperating with the antenna. A radar processor is connected to the radar transmitter and radar receiver to account for the Faraday rotation introduced by propagation through the ionosphere by estimating an individual ionospheric distortion for each received echo pulse based upon a measured Faraday rotation, and reducing the ionospheric distortion for each received echo pulse based upon the estimated individual ionospheric distortion associated therewith for providing a compensated echo pulse.
摘要:
A synthetic aperture radar (SAR) compensates for ionospheric distortions based upon measurement of the group delay, particularly when operating in the VHF/UHF band. The SAR is based upon a multi-input multi-output (MIMO) technique for estimating the effective ionospheric conditions, which is referred to as the group delay approach. The group delay approach is divided into a 1-dimensional (range) approach and a 2-dimensional (range and cross-range) approach. The group delay measures the effective or observed TEC, which is used to reduce the ionospheric distortion.
摘要:
The system and method prevents reception of calls to a mobile cellular device within a relatively small area or zone, with minimal inconvenience to the public by also permitting outgoing transmissions. The mobile cellular device has a wirelessly settable parameter associated therewith enabling establishment of an inbound call. A selective call blocker includes a receiver, a transmitter, and a selective call blocking controller cooperating with the receiver to determine the wirelessly settable parameter. The selective call blocking controller also cooperates with the transmitter to wirelessly change the wirelessly settable parameter to selectively block an inbound call to the mobile cellular device and without defeating the capability of the mobile cellular device to establish an outbound call.
摘要:
A receiver includes a matched filter matched to a synch pulse and generates a matched filter output signal having peaks and valleys with one of the peaks corresponding to the synch pulse. An orthogonal filter is inversely matched to the synch pulse and generates an orthogonal filter output signal having peaks and valleys with one of the valleys corresponding to the synch pulse. A detector determines the synch pulse based upon a largest difference between the matched filter output signal and the orthogonal filter output signal.
摘要:
A communications device includes a time/frequency error measurement circuit that receives a communications signal and measures its timing and frequency errors. A Kalman filter receives the communications signal from the time/frequency error measurement circuit and processes the signal using a multi-level state error covariance matrix P for controlling the Kalman gain in the Kalman filter. An on-line monitoring circuit is operative with the Kalman filter for monitoring the actual state errors in time and frequency and controlling the state error covariance matrix P based on a measured error threshold.