CAS Seminar

Götz Pfander

(Jacobs University)

"Local approximation and quantization of operators with bandlimited Kohn-Nirenberg symbols"

Date: Wed, February 16, 2011
Time: 14:15
Place: Research I Seminar Room

Abstract: Recent results in operator identification allow for the recovery of a bounded operator with bandlimited Kohn-Nirenberg symbol from its output on an identifier signal. However, the reconstruction formulas do not permit the introduction of additional redundancy in the frame used for recovery, as it would be desirable for signal processing applications; for example coarse quantization. In this presentation, we show how such redundant representations can be obtained from the output corresponding to suitable identifiers. Coarsely quantizing the resulting representation then yields a good approximation of the operator. In addition, we show locality, i.e., to approximate the action of the operator on functions with a given time-frequency localization, only information corresponding to the localization region is needed.