3. In an additive white Gaussian noise channel with the noise power-spectral density of No/2, two equi-probable messages are transmitted by: (At S₁(t)=T' 0 ≤ t≤ T $2(t) = A(1-7), 0 ≤t ≤T 0, otherwise 0, otherwise a) Determine the impulse response of the matched filters to the signals. b) Determine the structure of the optimal receiver. c) Determine the probability of error.