In this paper, a nonconforming mixed finite element method (FEM) is presented
to approximate time-dependent Maxwell’s equations in a three-dimensional
bounded domain with absorbing boundary conditions (ABC). By employing traditional
variational formula, instead of adding penalty terms, we show that the discrete
scheme is robust. Meanwhile, with the help of the element’s typical properties
and derivative transfer skills, the convergence analysis and error estimates for semidiscrete
and backward Euler fully-discrete schemes are given, respectively. Numerical
tests show the validity of the proposed method.