If the variance $$\sigma _d^2$$ of d(n) = x(n - 1) is one-tenth the variance $$\sigma _x^2$$ of a stationary zero-mean discrete-time signal x(n), then the normalized autocorrelation function $${R_{xx}}\,(k)\,/\,\,\sigma _x^2\,at\,\,k\,\, = \,1$$ is

For a random variable 'X' following the probability density function, p (x), shown in figure, the mean and the variance are, respectively.

Two resistors $$\,{R_1}$$ and $$\,{R_2}$$ (in ohms) at temperatures $${T_1}{}^ \circ K$$ and $${T_2}{}^ \circ K$$ respectively, are connected in series. Their equivalent noise temperature is.

Zero mean Gaussian noise of variance N is applied to a half wave rectifier. The mean squared value of the rectifier output will be: