Abstract: A hyperspectral radiation detector system collects infrared radiation concurrently from a plurality of adjacent infrared spectral bands. A collector system includes an optical train for receiving the incoming radiation, a disperser for separating the received infrared radiation into multiple adjacent bands of interest and a focal plane array for detecting the individual infrared bands and producing corresponding output signals. The focal plane array is an enhanced quantum well infrared photodetector having multiple physical dimensions of each detector varied in a predetermined manner to alter the frequency of responsivity of the detector to form the multi-band pixels of the received image. The output signals from the array can be processed as required to review selected bands of interest or to determine if certain types of targets are present within the received radiation.

Abstract: An error detection and correction system in which at least the highest order bit of each data word is given a greater protection against errors in transmission than lower order bits. Useful for digitized TV signals where errors in received high order bits have much worse effect on picture quality than errors in low order bits. A parity is generated for each data word in accordance with a self-orthogonal convolutional code constructed by the use of the base elements of a difference triangle for each bit of the data word, the difference triangles being disjoint, the triangle associated with the highest order bit or bits having a large number or numbers of base elements, and the triangles associated with the lowest order protected bit or bits consisting of a single base element. Errors in received code words are detected and corrected in a decoder including majority logic threshold detectors. Error correcting feedback to the syndrome shift register is limited to errors detected in the high order bits.