Patents Assigned to Litton Applied Technology
  • Patent number: 5781144
    Abstract: A method and apparatus for high speed denoising of an input signal received by a radar warning receiver (RWR) system. The novel system digitizes the input signal into sample windows each having a number of sample data points. The novel system includes a signal transformation processor system which convolves Haar wavelet basis functions across individual time segments of the input signal to produce sets of coefficients. Signal noise is poorly represented by the selected Haar wavelet basis functions while expected pulse signal characteristics are well represented by the basis functions. Within the wavelet transformation process, a plurality of frequency resolution levels are simultaneously determined, each frequency resolution level having a fixed number of correlation coefficients equal to the number of sample points in the sample window. Each coefficient also corresponds to a different basis function, or a same basis function applied to a different time segment.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: July 14, 1998
    Assignee: Litton Applied Technology
    Inventor: Chen Hwa