Local average sampling and reconstruction with fundamental splines of fractional order

Abstract: We analyse sampling and average sampling techniques for fractional spline subspaces of $L^{2}({\mathbb{R}}).$ Fractional B-splines $\beta_{\sigma}$ are extensions of Schoenberg's polynomial splines of integral order to real order $\sigma > -1$. We present the interpolation with fundamental splines of fractional order for $\sigma \geq 1$ and the average sampling with fundamental splines of fractional order for $\sigma \geq \frac{3}{2}.$ Further, we generalise Kramer's lemma in the context of local average sampling.