Consider the signals $\{$sm$($t$)\}4$ m$=1$ below. At every T seconds, one of $\{$sm$($t$)\}4$ m$=1$ is transmitted with equal probability. T T T T$/2$ T T$/2$ t t t t $0000111111$ s $($t$)$ s $($t$)$ s $($t$)12$ s $($t$)34($a$)$ What is an orthonormal basis set for $\{$sm$($t$)\}4$ m$=1?($b$)$ How do you categorize this signal set? $($c$)$ Draw the optimum receiver. $($d$)$ Assuming that the transmitted signal goes through an additive white Gaussian noise channel with zero mean and powe