Joint Secure Transceiver Design for an Untrusted MIMO Relay Assisted Over-the-Air Computation Networks With Perfect and Imperfect CSI

In this paper, we investigate the physical layer security of an untrusted relay assisted over-the-air computation (AirComp) network, where each node is equipped with multiple antennas and operated in amplify-and-forward mode. The receives data from sensor sends them to access point (AP) first second time slot, respectively. AP applies artificial noise (AN) protect aggregation sensors’ being wiretapped by slot. particular, are interested minimizing distortion measured mean-squared error (MSE) via jointly optimizing beamforming matrices at all nodes, subject MSE constraint individual power constraints AP, sensor. case perfect channel state information (CSI), convert nonconvex minimization problem into a difference-of-convex (DC) form propose constrained concave-convex procedure that can obtain local minimum solve DC problem. We also generalize framework imperfect CSI additional interference term due incomplete cancellation considered, robust solved proposed inexact block coordinate descent algorithm. Numerical results presented show effectiveness our schemes.