An Investigation of Three Methods of Completing a Staggered Data Field on a Square Grid,
Abstract
Three methods are examined for estimating values for grid points without data, based on data values available at grid points distributed in a staggered manner on a square grid. One method uses the average of values at surrounding points. The other two involve interpolation formulas of greater sophistication: bicubic spline interpolation and Fourier Transform interpolation. All three methods are applied to square grids on which values of transcendental functions of known wave numbers are placed in a staggered fashion. The completed fields from each method are spectrally analyzed to determine the effect of the completion method on the known spectrum of the incomplete field. It is determined that all three methods tend to alias high wave number components to lower wave number components. In addition, a spectral spreading is observed in the bicubic spline technique. The Fourier Transform method results in the least amount of aliasing, especially when the incomplete field is made up primarily of low wave number components. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 24, 1979
- Accession Number
- ADA082330
Entities
People
- Donald C. Norquist