Irrational filtering – what, why and how?

报告学者:YangQuan Chen

报告者单位:Nanyang Technological University

报告时间:2024年7月6日(周六)9:15-9:50

报告地点:红果园三层多功能厅 

报告摘要:Described by finite dimensional linear time invariant (LTI) rational transfer functions, digital filters are classified as IIR (infinite impulse response) and FIR (finite impulse response) types. What about infinite dimensional irrational transfer functions? These are called “Irrational Filtering”. This talk will explain what such irrational filters are with some motivating examples from standard heat transfer to the so-called Bode’s Ideal Cut-Off  (BICO) low-pass filters. Then we explain why irrational filtering is important and useful in practice. In addition to the frequency domain characterizations, we present another important use in the so-called Gaussianization process so that heavy-tailed noise can be converted to Gaussian noise after the irrational filtering, similar to whitening filtering using rational filters. Finally, we present how to implement the irrational filters using the “impulse-response-invariant discretization” (IRID) idea based on NILT (numerical inverse Laplace transform) and Prony technique. Worked out examples are given for illustration of the code. 

简介:YangQuan Chen earned his Ph.D. from Nanyang Technological University, Singapore, in 1998. He had been a faculty of Electrical Engineering at Utah State University (USU) from 2000-12. He joined the School of Engineering, University of California, Merced (UCM) in summer 2012 teaching “Mechatronics”, “Engineering Service Learning” and “Unmanned Aerial Systems” for undergraduates; “Fractional Order Mechanics”, “Nonlinear Controls” and “Advanced Controls: Optimality and Robustness” for graduates. His research interests include mechatronics for sustainability, cognitive process control, small multi-UAV based cooperative multi-spectral “personal remote sensing”, applied fractional calculus in controls, modeling and complex signal processing; distributed measurement and control of distributed parameter systems with mobile actuator and sensor networks. He is listed in Highly Cited Researchers by Clarivate Analytics from 2018 to 2021. He received Research of the Year awards from USU (12) and UCM (20). Most recently he started with Dr. Bruce J. West a new book series of CRC Press on AFC4STEM and established a new section for Fractals and Fractional journal on “Optimization, big data and AI/ML”