Scan Conversion and Interpolation
The Scan Conversion is to take the filtered RF vector line data and put it into a presentable form for display. It converts the polar coordinates to rectangular pixel positions. Normally interpolation is done at the same time during conversion.
An enlargement of the polar coordinate scan lines overlaid on the raster rectangular pixel grid indicates the problem. Not only do the scan lines rarely intersect the pixel locations, but also each spatial position in the sector presents a different interpolation because the vectors change angle and are closer toward the apex of the sector. Early attempts at interpolation caused severe artifacts, such as Moire's pattern, and unnatural steps and blocks in the image.
New approach has been developed for a fast 2D interpolation and conversion for a better image quality.
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