Error Performance Analysis of Distributed Spatial Modulation System with UAV Relays

In this paper, we present the error performance of a distributed spatial modulation (DSM) system with unmanned aerial vehicle (UAV) relays where the communication between ground terminals and UAV relays is affected by both path loss and flat Rician-K fading. In the proposed scheme, the UAV relay node activates its data transmission, depending on both the symbol index and the success of cyclic redundancy checking (CRC). The bit error probability (BEP) for the source is derived and validated by Monte Carlo simulations. The effects of modulation technique, modulation order and, Rician-K fading channel parameter on the BEP for the source are investigated. Moreover, DSM is compared against single hop and decode and forward (DF) cooperative system, and it is shown that DSM provides a better error probability for Rayleigh fading channels.