Linear Time - Invariant Systems and Their Frequency Response
نویسنده
چکیده
So just what is a Linear Time-Invariant (LTI) system, and why should you care? Systems are used to perform signal processing. The effect of a system on the spectrum of a signal can be analyzed easily if and only if the system is LTI, as we will see in these notes. The ability to design a filter to perform a specific signal processing task (e.g., filter out noise, differentiate, equalize frequency distortion) requires an ability to analyze what a filter will do. We will show how to analyze the effect of a given LTI system on the spectrum of a signal. Then we will design LTI systems for low-pass filtering and differentiation. With a few exceptions (e.g., median filtering), most filters are LTI systems.
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