Resource Allocation Optimization for Secure Multidevice Wirelessly Powered Backscatter Communication With Artificial Noise

Wirelessly powered backscatter communications (WPBC) is an emerging technology for providing continuous energy and ultra-low power communications. Despite some progress in WPBC systems, resource allocation multiple devices towards secure (BC) efficient-energy harvesting (EH) requests a deep-insight investigation. In this paper, we consider system which full-duplex access point (AP) transmits multi-sinewave signals to (BDs) injects artificial noise (AN) their transmissions. To maximize the minimum harvested ensure fairness security of all BDs, formulate optimization problem by jointly considering time, splitting ratio between AN, signal allocation. For single-BD system, characterize achievable secrecy rate-energy region with non-linear harvester propose two algorithms solve maximization problem. We then analyze effect AN on BD’s rate through simulations proof-of-concept experiments. multi-BD iterative algorithm leveraging block successive upper-bound minimization (BSUM) techniques non-convex fair show its convergence complexity. Numerical results proposed achieves optimal equitable BDs satisfying constraint.