基于双稳阱内随机共振的OFDM信号检测方法研究

为了解决OFDM(orthogonal frequency division multiplexing)传输系统中接收端对微弱OFDM信号的检测问题,本文将双稳阱内随机共振系统与OFDM信号增强和解调过程相结合,推导了多载波信号激励下双稳阱内随机共振系统从零状态变化到势阱状态所需时间的解析表达式,分析了暂态响应导致的多载波信号在一个符号内的能量损失问题;推导了系统稳态输出方程,分析了稳态过程对子载波已调信号叠加直流偏置分量的问题;探讨了在不同系统参数和噪声强度下阱内随机共振对OFDM信号解调性能的影响。仿真结果表明:该方法可有效实现信号与噪声阱内协同作用,提高OFDM信号的检测性能。

三稳阱内随机共振在微弱OFDM信号检测中的应用研究

提出了一种基于三稳阱内随机共振的微弱OFDM信号增强与解调方法,对OFDM基带复信号驱动下的三稳阱内随机共振系统的动力学特性和系统性能进行了深入分析。首先,分别给出了三稳阱内随机共振系统动态方程和OFDM基带复信号数学模型;然后,分析了三稳阱内随机共振的暂态响应过程和稳态响应过程,推导了系统从零状态到共振平衡状态所需暂态时间的表达式,推导了阱内随机共振系统处于稳定状态时的系统输出信号表达式;最后,给出了基于双三稳阱内随机共振系统的OFDM基带复信号增强和解调处理过程,先将接收到的OFDM基带复信号按符号周期进行分段,对同相分量和正交分量两路信号同时进行阱内随机共振处理,并进行了仿真。仿真结果表明:三稳随机共振方法有效解决了低信噪比下微弱OFDM信号接收性能恶化的问题,提高了OFDM系统的抗噪性能。

细胞内钙离子体系中的双参数内信号随机共振

In a model of intercellular calcium ion system oscillations, internal stochastic resonance(ISR) is investigated under the modulation of two parameters, viz., degree of extracellular stimulation β and leak rate k f. When either β or k f is subjected to a noise, ISR can occur. When noise is added to the two parameters simultaneously, internal stochastic bi-resonance(ISBR) occurs. The distance to the bifurcation point is found to be able to enhance or suppress the ISBR, and to affect the number of peaks of ISR.

钙离子振荡体系中隐式和显式内信号随机共振

The dynamic behavior of calcium ion oscillations was investigated when noise was injected to the system located in a steady state and an oscillatory state,respectively.It was found that noise can contribute to phenomenon of implicit or explicit internal stochastic resonance(IISR or EISR),and that distance to bifurcation point was a key factor for controlling IISR or EISR.Then an external signal was added to the system,the result shows that IISR or EISR can not occur,implying an external signal destroys the cooperation of internal signal and noise.Furthermore,the difference and the similarity were discussed between IISR and EISR.