Physical layer security in cellular network in the presence of terrains

Physical layer security (PHYLS) has become an important factor to consider with the deployment of 5G small-cell network and the application of massive multiple-input-multiple-output (MIMO). In a real small-cell network, the environment contains various objects which may affect a propagating signal. Accordingly, this work investigates the performance of different strategies by building a propagation model for PHYLS in the presence of random terrains. The Monte Carlo simulation is used to perform the simulation for the affect of terrains under different scenarios. Furthermore, two different approaches for improving PHYLS in the outlined environment and their influence is discussed. This includes separate antenna selection (SAS) and strategical artificial noise (SAN). The performance of each approach is simulated and the results are analysed. Our findings indicate that the existence of terrain may negatively affect the PHYLS performance. However, by implementing the aforementioned techniques we can compensate for degrading PHYLS with the cost of radio frequency (RF) resources.