Miscellaneous · Signals and Systems · GATE ECE

Consider the function $$g(t) = {e^{ - t}}\,\,\,\sin (2\pi t)\,u(t)$$ where u(t) is the unit step function. The area under g(t) is_______________.

The waveform of a periodic signal x(t) is shown in the figure.

A signal g(t) is defined by $$g(t) = x\left( {{{t - 1} \over 2}} \right)$$.

The average power of g(t) is___________________________.

A discrete - time signal x[n] = $${\rm{sin(}}\,{\pi ^2}n)$$, n being an integer is

The phase response of a passband waveform at receiver is given by $$\varphi \,(f) = - 2\,\pi \,\alpha \,(f - {f_c}) - \,2\pi \beta \,{f_c}$$

where $${f_c}$$ is the centre frequency, and $$\alpha $$ and $$\beta $$ are positive constants. The actual signal propagation delay from the trasmitter to receiver is

For a periodic signal v(t) = 30 sin 100t + 10cos 300t + 6sin $${\rm{(500t + }}\,\pi /4)$$, the fundamental frequency in rad/s is

Consider an angle modutated signal $$x(t) = 6\,\,\cos \,[2\,\pi \, \times {10^6}t + 2\sin (8000\pi t)\,4\cos (8000\pi t)]$$ V.

The average power of x(t) is

The Dirac delta function $$\delta (t)$$ is defined as

A solution for the differential equation $$\mathop x\limits^. $$(t) + 2 x (t) = $$\delta (t)$$ with intial condition $$x({0^ - }) = 0$$ is

The function x(t) is shown in Fig. Even and odd parts of a unit-step function u(t) are respectively.

Let $$\delta (t)$$ denote the delta function. The value of the the integral $$\int\limits_{ - \infty }^\infty {\delta (t)} \,\,\cos \left( {{{3\,\,t} \over 2}} \right)dt$$ is

The ACF of a rectangular pulse of duration T is

The complex envelope of the bandpass signal $$x(t) = - \sqrt 2 \left( {{{\sin \,(\pi t/5)} \over {\pi t/5}}} \right)\,\sin \,\left( {\pi t - {\pi \over 5}} \right)$$, centered about $$\,f = {1 \over 2}\,\,Hz$$, is

An LTI system having transfer function $${{{s^2} + 1} \over {{s^2} + 2s + 1}}$$ and input x(t) = sin (t + 1) is in steady state. The output is sampled at a rate $${\omega _s}\,\,rad/s$$ to obtain the final output {y(k)}. Which of the following is true?

A Hilbert transformer is a

In the following scheme, if the spectrum M(f) of m(t) is as shown, then the spectrum Y(f) of y(t) will be:

As x is increased from $$ - \infty \,\,to\,\infty $$, the function $$f(x) = {{{e^x}} \over {1 + {e^x}}}$$

The derivative of the symmetric function drawn in Fig .1 will look like

Match the following and choose the correct combination.

GROUP 1
E- continuous and aperiodic signal
F- continuous and periodic signal
G- discrete and aperiodic signal
H- discrete and periodic signal

Group 2
1- Fourier representation is continuous and aperiodic
2- Fourier representation is discrete and aperiodic
3- Fourier representation is continuous and periodic
4- Fourier representation is discrete and periodic

The value of the integral $$\,I = {1 \over {\sqrt {2\,\,\pi } }}\int\limits_0^\infty {\exp \left( { - {{{x^2}} \over 8}} \right)dx} $$ is

Consider the sequence

$$x[n] = [ - \,4 - \,j5,\,\mathop {1 + j2}\limits_ \uparrow ,\,\,4]$$

The conjugate anti-symmetric part of the sequence is

Match each of the items, A, B and C, with an appropriate item from 1, 2, 3, 4 and 5

A. Fourier transform of a Gaussian function
B. Convolution of a rectangular pulse with itself
C. Current through an inductor for a step input voltage

1. Gaussian function
2. Rectangular pulse
3. Triangular pulse Ramp function
4. Rump function
5. Zero