Recent questions in Discrete-time Signals

Consider the $z$-transform $X(z)=5 z^2+4 z^{-1}+3 ; 0<|z|<\infty$. The inverse $z$-transform $x[n]$ is$5\; \delta[n+2]+3\; \delta[n]+4\; \delta[n-1]$$5\; \delta[n-2]+3\; ...

For an $\mathrm{N}$-point $\mathrm{FFT}$ algorithm with $\mathrm{N}=2^{\text {m}}$, which one of the following statements is $\text{TRUE}?$It is not possible to construct...

The transfer function of a discrete time $\text{LTI}$ system is given by$$H(z)=\frac{2-\frac{3}{4} z^{-1}}{1-\frac{3}{4} z^{-1}+\frac{1}{8} z^{-2}}$$Consider the followin...

A linear discrete-time system has the characteristic equation, $z^{3}-0.81 z=0$. The systemis stableis marginally stableis unstablestability cannot be assessed from the g...

A system is defined by its impulse response $h(n)=2^n u(n-2)$. The system isstable and causalcausal but not stablestable but not causalunstable and noncausal

Two systems $H_1(z)$ and $H_2(z)$ are connected in cascade as shown below. The overall output $y(n)$ is the same as the input $x(n)$ with a one unit delay. The transfer f...

The first six points of the $8$-point $\text{DFT}$ of a real valued sequence are $5,1-\mathrm{j} 3,0,3-\mathrm{j} 4,0$ and $3+\mathrm{j} 4$. The last two points of the $\...

For a vector $\overline{x} = \left[ x [0], x , \dots, x[7] \right],$ the $\text{8-point}$ discrete Fourier transform $\text{(DFT)}$ is denoted by $\overline{X} = DFT (\ov...

Consider two $16$-point sequences $x\left [ n \right ]$ and $h\left [ n \right ]$. Let the linear convolution of $x\left [ n \right ]$ and $h\left [ n \right ]$ be denot...

For a unit step input $u[n]$, a discrete-time $\text{LTI}$ system produces an output signal $\left ( 2\delta \left [ n+1 \right ] +\delta \left [ n \right ]+\delta \left ...

Consider the signals $x\left [ n \right ]=2^{n-1}u\left [ -n+2 \right ]$ and $y\left [ n \right ]=2^{-n+2}u\left [ n+1 \right ]$, where $u[n]$ is the unit step sequence. ...

Let $X\left[ k \right ] = k + 1,0\leq k\leq 7$ be $8$-point $\:\text{DFT}\:$ of a sequence $x[n]$.where $X\left [ k \right ]=\sum_{n=0}^{N-1}x \left [ n \right ]e^{-j2\pi...