Recent years have seen an increased use of electromagnetic fields in many applications in society. Common examples include wireless communication systems, radio frequency identification (RFID), non-destructive evaluation and testing, microwave imaging, radar applications, radio telescopes, etc. Each of these applications benefits from the electromagnetic fields in a different manner. As a result antenna technologies have received much interest to satisfy the needs of those systems.

The licentiate thesis propose an approach to carry out gradient-based topology optimization for the design of metallic antennas. The antenna design is formulated as an optimization problem that aims to maximize the energy received by the antenna and transmitted to a coaxial cable, which by reciprocity is equivalent to minimizing the antenna reflection coefficient. The antenna model is formulated by using the 3D Maxwell's equations in the time domain and the FDTD method is used to numerically solve the problem. The conductivities associated with each Yee edge in the design domain are considered as design variables, which implies a very detailed parameterization of the complete design domain. The gradient of the objective function is derived based on the FDTD discretization of Maxwell's equations and is expressed in terms of field solutions of the original antenna problem and an adjoint field problem. The numerical experiments showed the promising use of the proposed approach for the automatic design of metallic antennas.