In a very recent work it was shown how to systematically generate particle-like scattering states in wave transport through complex scattering systems [PRL 106, 120602 (2011)]. These beam-like states have a number of interesting properties like a highly collimated wave function and deterministic values of transmission through a system. Such properties are of importance for saving power in the signal transmission, for security issues (to avoid eavesdropping), for improving the signal quality as well as for the focusing of waves on a small spot. In view of such a broad range of possible applications, this diploma thesis will cover the theoretical side of a microwave realization of such particle like states in collaboration with the University of Nice, where the effect of all the imperfections, that an experiment typically comes along with, will be investigated and quantified. The second part of this diploma thesis will deal with the recently introduced so-called Constant-intensity waves [Nature Communications 6, 7257 (2015)]. This new type of wave has constant intensity in the presence of linear as well as nonlinear inhomogeneous media with gain and loss. The characterization of these waves as well as new possible applications will be part of this thesis.