سیگنالها و سیستمهاSignals & Systems
سیگنالهای پیوسته و گسسته، سیستمهای LTI، کانولوشن و تبدیلهای فوریه، لاپلاس و Z.
کنکور ارشد مهندسی کامپیوتر
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کارتها · 3
The Fourier transform turns convolution into multiplication, so an LTI system's output spectrum is just the input spectrum times the frequency response.
A pole-zero map is ambiguous: only the ROC — always a pole-free strip (Laplace) or ring (Z) whose side is fixed by causality or absolute-summability — pins down the signal and its stability verdict; two-sided signals intersect their causal and anti-causal ROCs, and a causal impulse response is read straight off the power-series (long-division) expansion of H(z).
Classify a system by testing four independent properties — linearity, time-invariance, causality, stability — and remember that any time-scaling or shifting of the input argument breaks time-invariance while a future argument breaks causality.