**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**30673

##### Evaluating Sinusoidal Functions by a Low Complexity Cubic Spline Interpolator with Error Optimization

**Authors:**
Abhijit Mitra,
Harpreet Singh Dhillon

**Abstract:**

We present a novel scheme to evaluate sinusoidal functions with low complexity and high precision using cubic spline interpolation. To this end, two different approaches are proposed to find the interpolating polynomial of sin(x) within the range [- π , π]. The first one deals with only a single data point while the other with two to keep the realization cost as low as possible. An approximation error optimization technique for cubic spline interpolation is introduced next and is shown to increase the interpolator accuracy without increasing complexity of the associated hardware. The architectures for the proposed approaches are also developed, which exhibit flexibility of implementation with low power requirement.

**Keywords:**
Optimization methods,
Arithmetic,
Hardware Design,
spline interpolator,
erroranalysis

**Digital Object Identifier (DOI):**
doi.org/10.5281/zenodo.1331445

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