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Results tagged with Search options user 4346
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A discrete signal or discrete-time signal is a time series consisting of a sequence of quantities.

The Discrete Hilbert Transform is an "ideal" (implying that this is not the practical implementation) linear time-invariant filter with input $x[n]$ having output $$\mathscr{H}\Big\{ x[n] \Big\} \tr … answered May 1 by robert bristow-johnson i think the only family of functions that are eigenfunctions to LTI systems the sole exponential. for continuous-time, if it's LTI:$$ y(t) = \int\limits_{-\infty}^{+\infty} h(u) \ x(t-u) \ du $$t … answered Mar 9 '16 by robert bristow-johnson x(t) and x(-t) are flipped left-to-right about the point t=0. that point of reflection at t=0 is determined by asking: "When is t and -t equal to the same value?"$$ t = -t \qquad \qquad …
answered Jun 4 '18 by robert bristow-johnson
your TA is, strictly speaking, incorrect and Matt is, strictly speaking, correct. however... you can take any discrete-time signal and associate that with a uniformly-sampled continuous-time signal: …
answered Dec 3 '15 by robert bristow-johnson
you can have memory of past outputs. thems would be $y[n-1], y[n-2]...$ and you can have memory of past inputs which would be $x[n-1], x[n-2]...$ and you know your current input $x[n]$. if the out …
answered Sep 20 '16 by robert bristow-johnson
same property that the impulse response of a causal, linear and time-invariant (LTI) system has.
answered Nov 18 '15 by robert bristow-johnson
"Does this mean discrete time systems are clocked so that the values only at discrete time are available to the system?" yes, but the system can do some mathematics to interpolate values in between …
answered Sep 20 '14 by robert bristow-johnson
assuming $\omega$ is real, if the form of $x[n]$ is how you've defined it above, your thinking is correct. doesn't matter if it's $+\omega$ or $-\omega$, the sinusoid behaves exactly the same. if in …
answered Jan 22 '16 by robert bristow-johnson
well, there's an old trig identity that you learned pre-calculus: $$\sin(\alpha + \beta) = \sin(\alpha)\cos(\beta) + \cos(\alpha)\sin(\beta)$$ or, alternatively $$\sin(\alpha) \sin(\beta) = \tfr … answered Mar 28 '18 by robert bristow-johnson you can apply the linearity and time-invarancy tests to the original recursive difference equation. in this case it's:$$ y[n] - y[n-1] = x[n] $$which is really$$ y[n] = x[n] + y[n-1] $$now, a … answered Oct 3 '14 by robert bristow-johnson alright, i'm gonna answer this with an argument that "opponents" to my rigid nazi-like position regarding the DFT have. first of all, my rigid, nazi-like position: the DFT and Discrete Fourier Serie … answered Nov 2 '14 by robert bristow-johnson From you FFT result, the raw data ("noisy") is two sinusoids where one has frequency nearly exactly 4 times that of the other. that adds up to a periodic or nearly periodic function of time. Then yo … answered Sep 19 '16 by robert bristow-johnson DSP code that i see and try to write usually has a lot fewer conditional execution constructs (if statements) than AI code does. answered Mar 14 '16 by robert bristow-johnson consider a general rational transfer function of order N, first with an equal number of zeros and poles:$$ \begin{align} H(z) & = A \prod_{n=1}^N \frac{z - q_n}{z - p_n} \\ & = A \frac{\prod_{n=1 …
answered Oct 9 '14 by robert bristow-johnson
a burst of what?? a burst of power/energy? a burst of data? because, if it was the former, it's like ham-radio CW. if the latter, might be a template or pattern matching thing. perhaps, if you ha …
answered Mar 12 '15 by robert bristow-johnson

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