Some unexpected behaviors of operators with small time-frequency dispersion
نویسندگان
چکیده
We study the approximation properties of pseudo-differential operators with small time-frequency dispersion, meaning that their spreading functions are supported in a neighborhood origin. It is commonly assumed for such H, output Hf can differ only little from scalar multiple input f. However, we disprove this heuristic statement using theory superoscillations. This reveals some unexpected behaviors dispersion.
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ژورنال
عنوان ژورنال: Journal of Pseudo-differential Operators and Applications
سال: 2023
ISSN: ['1662-999X', '1662-9981']
DOI: https://doi.org/10.1007/s11868-023-00513-x