Analytical and experimental performance evaluation of antenna misalignment in Ka-band wireless links

In this paper, we propose a model for the effect of misalignment of antennas due to mechanical vibrations and experimentally validate its accuracy in a Ka-band (26-40 GHz) transmission link. Our approach provides a valuable tool that is analytically tractable and physically simple to implement. To highlight the applicability of the model, a setup based on a centralized radio access network (C-RAN) transmitting and receiving wireless signals in the Ka-band is implemented. With this tool, the robustness of 5G networks to antenna misalignments can be evaluated in terms of bit-error rate. We show how the presence of misalignment in this type of systems induces an error floor observable in the bit-error-rate performance. A simple static decision threshold is implemented taking into account the amount of displacement and, directly related to that factor, on the expected number of fades per unit time. The closed-form expressions derived through this paper are in perfect agreement with the experimental measurements taken from the implemented system.