基于最大后验概率准则，以错误检测概率为测度，研究了加性噪声和乘性噪声共同作用下信号检测的问题。在乘性噪声强度不变的情况下，当信号是阈上时，错误检测概率随着加性高斯噪声强度的增加而单调增加，噪声总是干扰信号检测；当信号是阈下时，错误检测概率随着加性高斯噪声强度的增加而逐渐降低至一个最小值后再缓慢增加，适量的噪声有利于多元信号检测，即随机共振存在。在加性高斯噪声强度不变的情况下，当信号是阈上时，错误检测概率随着乘性噪声强度的增加而单调增加，噪声总是恶化信号检测性能；当信号是阈下时，错误检测概率随着乘性噪声强度的增加而单调下降并最终趋于稳定。这些结论有助于噪声改善多元信号检测。%Stochastic Resonance ( SR) is discussed in nonlinear multiple signal detection for additive noise and multiplicative noise based on the Maximum Posterior Probability ( MAP) criterion in the probability of detection error measure. In the case that multiplicative noise intensity is fixed,when the signal is suprathreshold,the probability of detection error increases monotonously with the additive Gaussian noise intensity and noise always interfere signal detection;when the signal is subthreshold,with the increase of additive Gaussian noise in-tensity,the probability of detection error gradually reduces to a minimum value and then increases slowly and the noise can improve the signal detection,i. e. ,SR exists. In the case that additive noise intensity is fixed,when the signal is suprathreshold,the probability of de-tection error increases monotonously with the multiplicative noise intensity which indicates that noise is always deteriorate signal detection performance;when the signal is subthreshold,the probability of detection error decreases monotonously and finally tends to a steady value with the increasing of multiplicative noise intensity. These conclusions can be able to be helpful for noise improving multiple signal detec-tion.
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