Boundedness of New Type Fourier Integral Operators with Product Structure

We investigate a class of Fourier integral operators with weakened symbols, which satisfy a multi-parameter differential inequality in ${\mathbb{R}}^n$. We establish that these operators retain the classical $L^p$ boundedness and the $H^1$ to $L^1$ boundedness. Notably, the Hardy space considered here is the traditional single-parameter Hardy space rather than a product Hardy space.