Most of the radar cross section (RCS) calculations are done in frequency domain. In this report we investigate if the more general time domain solvers can be used with reasonable efficiency for RCS calculations. The wave equation is solved in a ID domain. At one boundary the in-coming wave is known and at the other, the wave is reflected. We investigate three different cases. In the first case a periodic wave is sent from one boundary and reflected at the other, in the second case a pulse is sent and in the third case, the Helmholtz equation, corresponding to the first case is solved. The orders of accuracy are calculated and the efficiencies are estimated in all the three cases. More efficient algorithms, which take advantage of the precise location of the signal, are also constructed.