Design and implementation of reconfigurable smart antenna beamforming architecture for secure node localisation applications

Smart antenna beamforming enables precise node localisation by counteracting physical layer attacks. A pattern with a narrower beamwidth is useful for securely sending data to target nodes . It is possible to cancel interference from other nearby nodes while steering deep nulls and maintaining lower sidelobe levels in the pattern. Conventional algorithms based on beam steering or null steering are not very effective in a hostile radio environment. Due to distance and angle estimation errors, they may extend coverage to malicious nodes. This paper presents a beamforming system based on PSO (particle swarm optimisation) and its subsequent implementation on a reconfigurable architecture. This system incorporates all the desired beam attributes into a reference template. It includes a linear array with non-uniform element excitations and a CORDIC (coordinate rotation digital computer) block to generate the array steering vector. It generates an optimal beam by iteratively optimising the weight vector using the PSO algorithm. The beamforming architecture is implemented using FSMD (finite state machine with datapath) design technology. Its performance is tested on a dedicated FPGA (field programmable gate array) board, with multiple fixed-point hardware-level simulations to evaluate the beamforming accuracy and computational overhead. The results corroborate its competence, comparable to existing systems.