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Linear, Time-invariant Systems

Consider the following system in which h(t) denotes the impulse response of a linear, time-invariant system.


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Throughout this problem, h(t) is given by

\begin{displaymath}h(t) = \Pi(\frac{t-\frac{\tau}{2}}{\tau}) = \left\{
\begin{ar...
... $0 \leq t \leq \tau$ }\\
0 & \mbox{else.}
\end{array}\right.
\end{displaymath}

1.
Compute the Fourier transform H(f) of h(t).
2.
Assume for the remainder of the problem, that the input signal x(t) equals $\Pi(\frac{t-\frac{t_0}{2}}{t_0})$. Assume $\tau > t_0$. Determine the signal s1(t) and the Fourier transform S1(f). Plot s1(t).
3.
Determine the signal s2(t) and the Fourier transform S2(f). Plot s2(t).
4.
Determine the signal s3(t) and the Fourier transform S3(f). Plot s3(t).
5.
Compute the output signal y(t) when $x(t)=\Pi(\frac{t-\frac{t_0}{2}}{t_0})$ is the input. Also, compute the Fourier transform Y(f). Plot y(t).
6.
Determine the impulse response and frequency response of the overall system, i.e., the system with input x(t) and output y(t).



Prof. Bernd-Peter Paris
2002-04-22