Page 30 - Schaum's Outline of Theory and Problems of Signals and Systems

CHAP. 11 SIGNALS AND SYSTEMS

H. Stable Systems:
A system is bounded-input/bounded-output (BIBO) stable if for any bounded input x
defined by

the corresponding output y is also bounded defined by

where k, and k, are finite real constants. Note that there are many other definitions of
stability. (See Chap. 7.)

I. Feedback Systems:
A special class of systems of great importance consists of systems having feedback. In a
feedback system, the output signal is fed back and added to the input to the system as
shown in Fig. 1-16.

- -
Fig. 1-16 Feedback system.

Solved Problems

SIGNALS AND CLASSIFICATION OF SIGNALS

1.1. A continuous-time signal x(t) is shown in Fig. 1-17. Sketch and label each of the
following signals.
(a) x(t - 2); (b) x(2t); (c) x(t/2); (dl x(-t)

-2-10 12 3 4 5 t
Fig. 1-17