Thought this might be interesting. NSA granted a series of new patents these last days... Yours Bo Elkjaer United States Patent 6,084,534 Postol July 4, 2000 Method for efficient storage and transmission of the centroids of a leech lattice quantizer Abstract A method of lattice quantizing a 24-long data point to minimize storage requirements by acquiring the data point, multiplying each coordinate of the data point by the square root of 8 to form an inflated data point, finding the closest point of the inflated Leech lattice by any method, creating a signal packet, and transmitting the packet to a receiver. The receiver receives the signal packet, recovers the inflated lattice point with the aid of a table of 89 of the 4096 codewords of the extended Golay code, replaces each one in the inflated lattice point by the reciprocal of the square root of 8 of the same polarity, replaces each 2 in the inflated lattice point by 2 divided by the square root of 8 of the same polarity, replaces each 3 in the inflated lattice point by 3 divided by the square root of 8 of the same polarity, replaces each 4 in the inflated lattice point by 4 divided by the square root of 8 of the same polarity, and replaces each 5 in the inflated lattice point by 5 divided by the square root of 8 of the same polarity in order to recover the data point. ... United States Patent 6,085,340 Postol July 4, 2000 Method of lattice quantization that minimizes storage requirements and computational complexity Abstract A method of lattice-quantizing an eight-long data point to minimize storage requirements and computational complexity by acquiring the data point, multiplying each coordinate of the data point by the square root of two to form an inflated data point, rounding each coordinate of the rounded and inflated data point to the nearest integer, reducing modulo-two each coordinate of the rounded and inflated data point to form an initial codeword, multiplying a parity-check matrix of an eight-bit Extending Hamming Code by the result of the last step to form a syndrome, correcting any single-bit errors and double-bit errors, if any, in the initial codeword and the rounded and inflated data point, creating a signal packet if the codeword does not contain any single-bit errors and double-bit errors, and transmitting the signal packet to a receiver. The receiver receives the signal packet, recovers the intended codeword from the table of sixteen codewords in the Extended Hamming Code, modifies the codeword according to the signal packet in order to recover the rounded and inflated data point, replaces each one in the rounded and inflated data point by the reciprocal of the square root of two of the same polarity, and replaces each two in the rounded and inflated data point by the square root of two of the same polarity in order to recover the data point. ... United States Patent 6,081,634 Attard June 27, 2000 All-fiber optically-controlled optical switch Abstract The present invention is an optical switch that includes a first optic fiber waveguide, a second optic fiber waveguide, and a third optical waveguide. The three waveguides are in the same plane. The third optical waveguide may be an optic fiber or a slab waveguide. The first and second optic fiber waveguides are close enough to exhibit evanescent wave coupling under non-interference conditions. The second optic fiber waveguide is between the other two waveguides and closer to the third optical waveguide. The first and second optic fiber waveguides have identical propagation constants. An information-bearing optical signal is applied to the first optic fiber waveguide. An optical control signal applied to the third optical waveguide controls its propagation constant and, therefore, controls whether or not switching occurs between the first and second fiber optic waveguides. The optical switch may be made to be normally on or normally off. ... United States Patent 6,081,323 Mahgerefteh , � et al. June 27, 2000 Measurement of Raman gain spectrum in optical fiber Abstract An apparatus and method for measuring the spectral dependence of the Raman gain coefficient in optical fibers is presented. This approach measures the power level of Raman scattering in both a walk-off limited region and a physical fiber length limited region and, from these measurements, extracts the spectral dependence of the Raman gain coefficient. Access to these two regions is accomplished through control of the excitation pulse temporal width and relies on fiber dispersion to separate the excitation light from the Raman scattered light for short pulse widths. This approach measures the spectral dependence of the Raman gain without the necessity of absolute power measurement of the Raman scattered light, the need for a reference standard, or the need of a frequency tunable secondary optical source. ... United States Patent 6,080,996 Yang June 27, 2000 Unipolar three-terminal resonant-tunneling transistor Abstract The present invention discloses both an n+ and a p+ unipolar, three-terminal, resonant-tunneling transistor that can be operated as a hot-electron transistor or a field effect transistor at temperatures at least as low as 77 degree Kelvin. The doped first terminal (collector or gate) is made of 3D metal or semiconductor material. An undoped insulating barrier is deposited on the first terminal. The doped electrically-contacted second terminal (emitter or source), made of a 2D semiconductor material, is deposited on the insulating barrier. An undoped double-barrier resonant-tunneling structure is deposited on the second terminal. A doped third terminal, made of 3D metal or semiconductor material, is deposited on a portion of the double-barrier resonant-tunneling structure. A doped tunneling-contact, made of 3D metal or semiconductor material, is deposited on the double-barrier resonant-tunneling structure so that the tunneling contact is isolated from the third terminal. At a temperature of at least as low as 77 degrees Kelvin, dc current gain between the third terminal and the tunneling-contact is observed when a bias voltage or current is applied to the first terminal. With a bias applied to the first terminal, majority carriers from the tunneling-contact tunnel through the double-barrier resonant-tunneling structure to the second terminal. The majority carriers propagate along the second terminal and tunnel through the double-barrier resonant-tunneling structure to the third terminal. ... >>Bevar naturen: Sylt et egern.<< >>URL: http://www.datashopper.dk/~boo/index.html<< >>ECHELON URL:<< >>http://www1.ekstrabladet.dk/netdetect/echelon.iasp<<
