![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
Consider a communication channel corrupted by noise. Let X be the value of the transmitted signal and Y the value of the received signal. Assume that the conditional density of Y given X is Gaussian, that is, and that X takes on only the values +1 and −1 equally likely. What is the conditional density of X given Y , that is, ?