Stochastic Resonance Assisted Successive Interference Cancellation Receiver for Signal Detection Performance Improvement

Abstract

In the 5th-generation mobile communication system (5G), a multiuser multiplexing scheme, nonorthogonal multiple access (NOMA), has been proposed to accommodate the massive connectivity in wireless communication systems. By nonorthogonality, NOMA allows the use of a new domain that is ineffectively utilized in conventional orthogonal multiple access (OMA) schemes. In power-domain NOMA (PD-NOMA), user signals are allocated different power levels and multiplexed by superposition coding at a transmitter. NOMA employs interference cancellation schemes such as successive interference cancellation (SIC) at receivers to avoid interference between the signals. The use of nonlinear systems such as low-resolution analog-to-digital converters (ADCs) is favorable in terms of energy consumption since the load of SIC processes increases proportionally to the number of users. However, on the other hand, the use of nonlinear systems leads to the degradation of signal detection performance. Stochastic resonance (SR) is a nonlinear phenomenon that improves the response of nonlinear systems to weak power signals. In this paper, we propose the application of SR to the nonlinear system in SIC. Through computer simulations, we show that the proposed method can improve the signal detection performance without losing the advantage of low energy consumption.