Application Research Of Bistable Stochastic Resonance In Weak OFDM Signal Detection

Considering that the bistable stochastic resonance system can enhance the weak input signal,this paper applies bistable stochastic resonance to the preprocessing of weak OFDM(Orthogonal Frequency Division Multiplexing)signals to improve the system detection performance.In the background of Gaussian white noise,a bistable stochastic resonance system model with weak OFDM signal as input signal is established.The interwell stochastic resonance system of OFDM and the intrawell stochastic resonance system of OFDM are studied.The signal detection process of the system is simulated.The main research contents of the thesis are:1?The basic principles of bistable stochastic resonance and OFDM are expounded.The system model of bistable stochastic resonance is introduced.The adiabatic approximate stoch-astic resonance theory,and linear response stochastic resonance theory in stochastic resonance classical theory are deduced and analyzed in detail.The role of stochastic resonance theory in weak signal detection.2?In the background of Gaussian white noise,the weak periodic sinusoidal signal is used as the external driving signal,and the bistable stochastic resonance signal detection system model is established.The mechanism of the bistable stochastic resonance theory as the signal detection method is analyzed.The feasibility of the weak signal detection by the bistable stochastic resonance method is verified by simulation experiments.The numerical solution algorithm of the dynamic equation Lange'vin equation is given.3?Introducing bistable stochastic resonance into the detection of weak OFDM signals.A bistable interwell stochastic resonance system model for OFDM signals is established.The detection performance of the bistable interwell stochastic resonance system for weak OFDM signals under the two adjustment methods of noise and system parameters is studied.The degree of aggregation of the OFDM signal constellation at the receiving end illustrates the detection effect of the bistab interwell stochastic resonance system on weak OFDM signals.4?The single-well approximation model of the bistable system is derived,and the intrawell stochastic resonance system of OFDM signal is established.The detection performance of the intrawell stochastic resonance system for weak OFDM signals under noise regulation and parameter adjustment is studied.In the simulation,the degree of aggregation of the OFDM signal constellation reflects the detection effect of the intrawell stochastic resonance system on the weak OFDM signal.The results show that:(1)stochastic resonance theory can be used for the detection of weak OFDM signals;(2)in the background of Gaussian white noise,both the interwell stochastic resonance system and the intrawell stochastic resonance system can enhance the weak OFDM signal Transmission,improves the detection performance of the weak OFDM signal at the receiving end;(3)Both noise adjustment and parameter adjustment can make the bistable stochastic resonance system of the OFDM signal reach the resonance state,and both have the optimal range of values,so that the resonance effect is the most Strong,that is,the system works best for weak OFDM signals.