초록 ▼

A correlation tracker for generating correlation error tracking signals over an entire video frame. Video information from a scanning receiver is inputted into the correlation tracker in serial form. The correlation tracker first incorporates apparatus to generate a reference map in pixel format. Re

A correlation tracker for generating correlation error tracking signals over an entire video frame. Video information from a scanning receiver is inputted into the correlation tracker in serial form. The correlation tracker first incorporates apparatus to generate a reference map in pixel format. Reference map pixel information for one video frame plus one video line is stored in a memory to allow the calculation of azimuth and elevation optimal weighting values for each pixel in the field of view. Each video pixel of data being received during the current frame is then summed with the corresponding reference map pixel from the prior frame and the result multiplied by the appropriate weighting function. Each resultant product is then combined in an accumulator to form azimuth and elevation correlation error signals which are composite indications of the frame-to-frame correlation over the entire field of view. The weighting factors for each pixel are also combined and accumulatively added over the entire image plane to form three adaptive scale factors at the end of each frame which are combined with the azimuth and elevation correlation error signals to eliminate cross-coupling and generate cross-coupling-free correlation error signals. Drift compensation may also be provided by combining the adaptive scale factors and several predetermined constants to recursively calculate a drift correction which when combined with the cross-coupling-free correlation error signals generates drift-free correlation error signals.

대표청구항 ▼

A correlation tracker for generating correlation tracking error signals said tracker having a receiver for receiving electromagnetic information from a scene to form an input signal having a plurality of sets of pixel values each set representing pixel data for one video frame, said correlation trac

A correlation tracker for generating correlation tracking error signals said tracker having a receiver for receiving electromagnetic information from a scene to form an input signal having a plurality of sets of pixel values each set representing pixel data for one video frame, said correlation tracker comprising: (a) a reference map generator for receiving said pixel values and generating a reference map having a plurality of reference map values corresponding to said pixel values; (b) a weighting function generator coupled to said map generator for generating at least one weighting value for each pixel value; (c) a scale factor generator coupled to said weighting function generator for combining the weighting values to form at least one pixel correlation scale factor and accumulating said pixel correlation scale factors to form at least one correlation scale factor for each video frame; and (d) a correlation error signal generator coupled to said weighting function generator, to said scale factor generator, and to said map generator for generating at least one correlation error value from said reference map pixel values, said input signal pixel values, and said weighting function for each pixel and accumulating a plurality of said correlation error values which is scaled by one of said scale factors to form at least one correlation error signal for each video frame.