We first introduce a new presentation for the mirabolic Hecke algebra $\mathscr{ H}_{ n,R}(q)$ over an arbitrary commutative ring $R$ and derive a new basis. Based on this presentation, specializing to the case of $\mathscr{ H}_n(q)$ over the field $\mathbb{ C}(q)$, we construct a basis for the cocenter of $\mathscr{ H}_n(q)$, which facilitates the definition of its character table. We further establish a Schur--Weyl duality between $\mathscr{ H}_n(q)$ and the quantum group $U_q(\mathfrak{ gl}_r)$. As an application, we obtain Frobenius character formulas for the irreducible characters of $\mathscr{ H}_n(q)$ within the ring of symmetric functions. Finally, we derive a recursive Murnaghan--Nakayama rule for the computation of the character table.

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Mirabolic Hecke algebras, Schur-Weyl duality and Frobenius character formulas