2-D Laguerre Distributed Approximating Functional: A Circular Low-Pass/Band-Pass Filter
Soo‐Chang Pei, Shih-Gu Huang · IEEE Transactions on Circuits & Systems II Express Briefs · 2019
The two-parameter family of Hermite distributed approximating functionals (HDAFs) is able to converge to the ideal low-pass filters. In this brief, we extend the concept of the HDAFs to two dimensions to develop the three-parameter family of 2-D Laguerre distributed approximating functionals (LDAFs). With the third parameter, the 2-D LDAFs can be used as either circular low-pass filters or band-pass filters. We show that the 2-D LDAF filters can converge to the ideal circular low-pass/band-pass filters. We develop two digitalization methods to compute the 2-D digital LDAF low-pass/band-pass filters from the closed-form expressions of the 2-D LDAFs without performing any optimization.