Abstract: Systems (100) and methods (400) for space-based geolocation. The methods involve receiving by at least two first satellites a maritime signal transmitted from a vessel on or near Earth. The first satellites are deployed in space so as to have overlapping coverage areas. The maritime signal (received at the at least two first satellites) is then used to determine a geographic location of the vessel on Earth using at least one of a Time Difference of Arrival (“TDOA”) and a Frequency Difference of Arrival (“FDOA”).

Abstract: A sensing and recovery system includes a sensing unit and a recovery unit coupled together. The sensing unit includes a sensor to generate a bandlimited continuous time analog signal, and a modulator coupled to the sensor to generate a modulated analog signal based upon modulation of the bandlimited continuous time analog signal at a modulating rate at least equal to a Nyquist rate for the bandlimited continuous time analog signal. A compressive sensing circuit is coupled to the modulator to generate a compressed sensed signal based upon conversion of the modulated analog signal at a sampling rate less than the Nyquist rate. The recovery unit recovers the bandlimited continuous time analog signal from the compressed sensed signal.

Abstract: A data handling system includes a compressive sensing unit that receives a source date file. A sparseness module compressive sensing unit generates a sparse source data file by inducing sparseness into the source data file. A measurement module within the compressive sensing unit generates a compressed sensed source data file from the sparse source data file and based on a sensing matrix. The compressed sensed source data file is to be transmitted to a remote data storage facility for storage. A recovery unit generates the source data file from the compressed sensed source data file retrieved from the remote data storage facility and based upon the sensing matrix.

Abstract: A data handling system includes a compressive sensing unit that receives a source date file. A sparseness module compressive sensing unit generates a sparse source data file by inducing sparseness into the source data file. A measurement module within the compressive sensing unit generates a compressed sensed source data file from the sparse source data file and based on a sensing matrix. The compressed sensed source data file is to be transmitted to a remote data storage facility for storage. A recovery unit generates the source data file from the compressed sensed source data file retrieved from the remote data storage facility and based upon the sensing matrix.

Abstract: A sensing and recovery system includes a sensing unit and a recovery unit coupled together. The sensing unit includes a sensor to generate a bandlimited continuous time analog signal, and a modulator coupled to the sensor to generate a modulated analog signal based upon modulation of the bandlimited continuous time analog signal at a modulating rate at least equal to a Nyquist rate for the bandlimited continuous time analog signal. A compressive sensing circuit is coupled to the modulator to generate a compressed sensed signal based upon conversion of the modulated analog signal at a sampling rate less than the Nyquist rate. The recovery unit recovers the bandlimited continuous time analog signal from the compressed sensed signal.

Abstract: A method for determining the location of a vehicle whose movement is constrained to a route whose location is fixed and known, such as a train. An initial estimate of location is made based upon information contained in a route database based on distance traveled from a reset point. The accuracy of the estimated vehicle location is improved through use of just two global positioning satellites.

Abstract: A system architecture and communication methodology for significantly reducing the size of an aircraft antenna required to provide full broadcast quality video communications with an aircraft via a satellite communications link includes a combination of video bandwidth compression, spread spectrum waveform processing and an electronically steered, circular aperture phased array antenna, that is conformal with an airframe surface of the aircraft. The combination provides sufficient signal power to the aircraft, enables interference from other satellites to be rejected and maintains the power spectral density of the satellite's video transmission within FCC requirements. The polarization of the receive array is aligned with that of the incoming beam from the relay satellite by means of an error signal feed back path to control the steering weights of the array.