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Optimum Receiver Design

The following binary signal set is used to transmit equally likely messages over an additive white Gaussian noise channel (spectral height $\frac{N_0}{2}$),

\begin{displaymath}
\begin{array}
{cc}
s_0(t) = & \left\{ 
\begin{array}
{cl}
5 ...
 ... \leq t \leq T$}\\ 0 & \mbox{else}\end{array}\right.\end{array}\end{displaymath}

1.
Draw a block diagram of the optimum receiver.
2.
Compute the probability of error for this receiver.
3.
Repeat parts (a) and (b) for the following signal set:

\begin{displaymath}
\begin{array}
{cc}
s_0(t) = & \left\{ 
\begin{array}
{cl}
7 ...
 ... \leq t \leq T$}\\ 0 & \mbox{else}\end{array}\right.\end{array}\end{displaymath}

4.
Sketch and accurately label a signal space diagram, including decision boundaries, for each of the two signal sets above.
5.
Verify that both of the above signal sets require the same average power to transmit a bit. Then compare their performance with respect to the minimum probability of error. Which signal set do you prefer?


Prof. Bernd-Peter Paris
3/3/1998