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$$x[n] = \frac{3\sin{(3\pi\frac{n}{4})}}{\pi n}$$

What is the Discrete Time Fourier Transform $X(e^{jw})$ of $x[n]$?

Thanks.

I need to plot a graph of $X(e^{jw})$ for the sinc function x[n]. I know it is a rectangular waveform.....

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    DT? What exactly do you mean?2011-09-16
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    @J. M.: I'm guessing it's the discrete FT, i.e. for $N$ points $\{f(k) | k = 0,\ldots,N-1 \},$, you get $$f(n) \mapsto \sum_k e^{-2\pi i nk/N} f(k).$$2011-09-16
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    @Gerben : I think it is DTFT but not DFT.2011-09-16
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    I'm asking because OP **should** have supplied what formula he's supposed to use, sign/normalization and all...2011-09-16
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    I need to plot a graph of $X(e^{jw})$ for the sinc function x[n].2011-09-16
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    @zingsi123 You should consider transferring this question to the newly established site dsp.stackexchange.com for digital signal processing.2011-09-17
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    The $x(n)$ $\ (n\in{\mathbb Z})$ are the Fourier coefficients of a certain $2\pi$-periodic function $X(\cdot)$. The problem consists in finding an expression for $X(\cdot)$.2013-01-14

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