MATLAB Signal Processing

Question 1

Which MATLAB function computes the Fast Fourier Transform of a signal vector x?

Accepted Answer

fft(x)

Answer

dft(x)

Answer

fourier(x)

Answer

transform(x)

Question 2

What inputs does the MATLAB `filter(b, a, x)` function require?

Accepted Answer

Numerator coefficients b, denominator coefficients a, and input signal x

Answer

Only the input signal x and sampling frequency fs

Answer

Filter order N and cutoff frequency Wn only

Answer

Transfer function H and sampling rate fs

Question 3

According to the Nyquist-Shannon theorem, what is the minimum sampling rate required to reconstruct a signal with maximum frequency f_max?

Accepted Answer

2 * f_max

Answer

f_max

Answer

f_max / 2

Answer

4 * f_max

Question 4

Which MATLAB function designs a FIR filter using the window method given filter order n and normalized cutoff frequency Wn?

Accepted Answer

fir1(n, Wn)

Answer

butter(n, Wn)

Answer

cheby1(n, Rp, Wn)

Answer

ellip(n, Rp, Rs, Wn)

Question 5

What does the MATLAB `freqz(b, a)` function compute?

Accepted Answer

The frequency response of a digital filter defined by coefficients b and a

Answer

The zero-frequency component of the FFT

Answer

The resonant frequency of an analog filter

Answer

The resampled signal at a new frequency

Question 6

Which MATLAB function computes the linear convolution of two discrete-time sequences u and v?

Accepted Answer

conv(u, v)

Answer

xcorr(u, v)

Answer

dot(u, v)

Answer

convolve(u, v)

Question 7

In MATLAB, how do you generate a 1 Hz sine wave sampled at 100 Hz for 1 second?

Accepted Answer

x = sin(2*pi*1*t); where t = 0:1/100:1

Answer

x = sin(t); where t = linspace(0,100,1)

Answer

x = sinc(t); where t = 0:1:100

Answer

x = cos(2*pi*100*t); where t = 0:1/1:1