Linear time-invariant (LTI) systems are the most widely used systems in signal processing. In this lesson you will develop a deeper understanding for the role of the impulse response of LTI systems. You will learn how linearity and time invariance result in the convolution sum for expressing the output of an LTI system in terms of the input and impulse response. You will also learn how the impulse response of parallel and cascade combinations of LTI systems is determined, and the conditions required of the impulse response for the system to be stable.
Deeper understanding of the impulse response description will increase your insight into the characteristics and behavior of LTI systems.