Consider a binary, digital communication system which uses pulses g (t) and − g (t)for transmitting bits over an AWGN channel. If the receiver uses a matched filter, which one of the following pulses will give the minimum probability of bit error?

The state variable representation of a system is given as $$$\eqalign{ & \mathop x\limits^ \bullet = \left[ {\matrix{ 0 & 1 \cr 0 & { - 1} \cr } } \right]x;x\left( 0 \right) = \left[ {\matrix{ 1 \cr 0 \cr } } \right] \cr & y = \left[ {\matrix{ 0 & 1 \cr } } \right]x \cr} $$$

The response y(t) is

By performing cascading and/or summing/differencing operations using transfer function blocks G₁(s) and G₂(s), one CANNOT realize a transfer function of the form

For the signal flow graph shown in the figure, the value of $$\frac{\mathrm C\left(\mathrm s\right)}{\mathrm R\left(\mathrm s\right)}$$ is