Abstract: An electronic detection system for detecting vibration patterns from physical events, such as engine knocking or articulated speech, senses a vibration source with a wideband transducer to provide a sensed signal, then converts this signal to energy amplitude and spectral frequency form to extract detectable features of the vibration pattern. Events are detected when a controller determines that the sensed energy and spectral data exceed adaptively-predetermined energy and spectral thresholds, preferably for a duration exceeding predefined time windows.

Abstract: An encoder for selected linear error correcting codes, such as a BCH code, uses relatively low-speed circuitry to generate parities for correcting the code. A parity matrix derived from the BCH generator matrix is provided as data to a generator vector whereby the generator vector is used as a logical shift function generator. When the logical shift function is applied to the rows of the parity matrix, columns of parity are shifted into an EXCLUSIVE-OR tree to produce the parity bit of the column. The parity bit of the column is then injected into a data stream forming the encoded symbol for transmission, attaching the parity word following the data word. The apparatus may be constructed making maximum use of the standard, commerically available, relatively low-cost integrated circuits, but it is nevertheless capable of operating at speeds in excess 1 GBPS.

Abstract: A hand-held spelling checker is disclosed employing a compact technique for storing information. A binary character code is assigned to each letter of the alphabet, and an additional series of binary codes are assigned to indicate a relationship between a subsequent letter and a preceding letter in a dictionary entry. For each letter in the dictionary, the sum of the codes of the binary character and its relationship with the preceding is stored in memory.

Abstract: A technique for communicating digital data through a noisy medium using phase modulated carrier signals. A multiphase clock drives parallel channels to sample the received signal, avoiding the need for a phase locked loop. Data is recovered from the noisy carrier by a two stage statistical filtering technique and pattern analysis of the filtered signals.

Abstract: A digital circuit to approximate the product of two numbers by shifting the bits in one number to higher significance positions by an amount equal to the bit position of the most significant "one" in the other number, useful in digital speech recognition and synthesis.