Precoder design and impulsive noise mitigation scheme for industrial wireless communications

In industrial wireless scenarios, the impulsive noise (IN) incurred by machine running or operation causes a serious influence on the power-limited industrial wireless communications. It is challenging to ensure efficient and reliable transmission with quality of service (QoS) guarantee for machinetype communication devices (MTCDs). Considering the IN in the industrial process, this paper establishes the multiuser multiple-input single-output (MU-MISO) orthogonal frequency division multiplexing (OFDM) system model, which combines transmitter and receiver design. Two precoding schemes are designed to improve communication effectiveness at the transmitter. More specifically, the precoder design scheme which combines semi-definite relaxation (SDR) with difference-of-two-convex-function (D.C.) iterative algorithm, is developed by utilizing the Dinkelbach method to improve the system effectiveness. To decrease the computational complexity, we devise the quadratic-based fractional programming (QFP) algorithm, which decouples the variables by using a quadratic transform method. On this basis, the IN mitigation scheme is studied to reduce the system error rate (SER) at the receiver. With the goal of improving the reliability of industrial wireless communications, we propose a hybrid nonlinear IN mitigation (HNINM) scheme and then derive its closed-form expression of SER. The simulation results show that the proposed QFP algorithm achieves superior performance while the HNINM scheme decreases the SER of industrial wireless communications.