Abstract: Described is a method for accurately reconstructing analog signals. The present invention considers a general parameter estimation problem, extends the utility of compressive sensing to real scenarios, and is able to accurately estimate center frequencies and amplitudes. Specifically, an unknown continuous analog signal comprising a set of arbitrary frequencies and amplitudes is received. A set of non-uniform samples of the unknown continuous analog signal is then obtained at multiple times. Finally, an iterative reconstruction process is utilized to determine a set of frequencies and a set of amplitudes that best fit the set of non-uniform samples in a global minimum problem in order to accurately reconstruct the continuous analog signal.

Abstract: A compressive sensor for sensing energy including a plurality of detectors for detecting a plurality of electromagnetic modes, wherein each detector has an output and detects at least one electromagnetic mode of the energy, a summer coupled to the plurality of detectors for forming a composite sum of the outputs of the plurality of detectors, and a plurality of switches, each respective switch coupled to a respective detector, wherein the respective switch may be switched to remove the respective detector from the composite sum.

Abstract: A time encoding machine (TEM) for time encoding an input signal includes a hysteresis quantizer having a time encoded sequence output and a random sequence generator having a random signal output coupled to the hysteresis quantizer for randomizing switching times of the hysteresis quantizer.

Abstract: An object-based image/video coding algorithm that encodes arbitrary shaped objects using LOTs defined on rectangular and L-shaped regions. The regions of support of the blocks in the L-shaped regions are extended to form tapered overlapping regions that meet at the object's exterior and concave corners. The overlapping regions taper to the corners with a slope having a magnitude .delta./.epsilon., where .delta. and .epsilon. are the amounts of overlap between the blocks. This allows the basis and tapered window functions to be defined in the L-shaped region and specifically in the tapered overlapping regions in a manner that maintains the orthogonality of the basis functions while providing a smooth transition at the edges.

Abstract: A codeword generator produces codewords in the form of digital electronic signals which may be employed, for example, in spread spectrum communications system or RADAR systems. The generator effects a mixing ergodic transformation upon a suitable irrational number to produce a complex number sequence. The generator truncates the complex number sequence to a predetermined length, thus forming a codeword. The generator then forms other codewords within a family by permuting this first codeword. Other families of codewords may be generated by employing another mixing ergodic transform to transform the same irrational number or another suitable irrational number.

Abstract: A reconfigurable optical beam splitter and method establishes replicated periods of optical phase shift regions across a liquid crystal cell to form an optical grating in the liquid crystal. A non-linear pattern of phase shift regions is established within each period of the grating to split an input beam into a multi-beam output, or to combine multiple input beams into a single output beam. The desired pattern of phase shift regions is established by applying corresponding voltage differentials across the cell, between an electrode array on one side of the cell and a common counter electrode on the other side. The voltage differential pattern can be dynamically changed to impart a corresponding dynamic reconfiguration of the output beam pattern.