This paper is concerned with a point-oriented finite volume time domain (FVTD) method in the Cartesian coordinate system and its application to the analysis of electro-magnetic wave propagation in a bended waveguide as well as radiation from and receiving by a horn antenna with a flange of arbitrary angle. The perfectly matched layer (PML) is used for the absorbing boundary conditions (ABC's). The boundary conditions for a perfect conductor not well suited to the Cartesian coordinate system are also proposed. According to this algorithm, the boundary conditions are satisfied in an average fashion at the conductor surface without changing the computational scheme. In this sense, numerical computations based on the present method are simple but flexible. Numerical results show good convergence.