  We study one of multidimensional inverse scattering problems for quantum
systems in a constant electric field, by utilization of the Enss-Weder
time-dependent method. The main purpose of this paper is to propose some
methods of sharpening key estimates in the analysis, which are much simpler
than those in the previous works. Our methods give an appropriate class of
short-range potentials which can be determined uniquely by scattering
operators, that seems natural in terms of direct scattering problems.
