FEM simulations for the wireless optical indoor communication channel

The finite-element method (FEM) has been successfully applied for finding approximate solutions to the radiosity equation which plays an important role in the field of computer graphics. The author shows how these methods can quite similarly be utilised for the calculation of the transfer function of the optical wireless communication channel. The analysis is performed in the frequency domain and is not restricted to a finite order of light reflections as is the case for the time-domain approaches known from the literature. The numerical results show that the Galerkin FEM approach increases the accuracy obtained for the received optical power and for the channel transfer function in the frequency region that is relevant to data transmission or, vice versa, it reduces the computational complexity for a given required accuracy.