In the digital communication system, signals in different frequency bands are

a) Orthogonal

b) Non orthogonal

c) Orthogonal & Non orthogonal

d) None of the mentioned

2. Properties of impulse function are

a) Symmetry

b) Time scaling

c) Shifting

d) All of the mentioned

3. Properties of Fourier transform are

a) Duality property

b) Time shifting property

c) Modulation property

d) All of the mentioned

4. A base-band signal can be up-converted using

a) Sine wave

b) Cosine wave

c) Filtering

d) None of the mentioned

5. A band-pass signal can be down-converted using

a) Sine wave

b) Cosine wave

c) Time delayed wave

d) None of the mentioned

6. In down-conversion multiplication with cosine wave is followed by

a) Low pass filter

b) High pass filter

c) Bandpass filter

d) Bandstop filter

7. ADSL has _____ information channels.

a) One

b) Three

c) Four

d) None of the mentioned

8. Fourier transform of a signal gives the

a) Frequency content

b) Bandwidth

c) Frequency content & Bandwidth

d) None of the mentioned

9. Random things in a communication system are

a) Timing offset

b) Device frequency

c) Attenuation

d) All of the mentioned