On-chip wireless optical communications among distant cores in chip multiprocessors can lead to a completely new approach to overcome the limits of current on-chip communication. In fact, using wireless connections mitigates the problems related to the design and the fabrication of hugely complex switching fabrics, where long paths suffer of crosstalk and loss issues. Implementing wireless communication at optical frequencies allows simplifications in network design and management. In this paper, a solution based on Vivaldi plasmonic antennas integrated with silicon waveguides is presented. Moreover, on-chip wireless propagation characteristics and point-to-point link performances in homogeneous and multilayered medium are investigated and discussed.