# Parameters of Mobile Multipath Channels

This set of Wireless & Mobile Communications Problems focuses on “Parameters of Mobile Multipath Channels”.

1. Power delay profile is represented as plots of __________ with respect to fixed time delay reference.

a) Relative received power

b) Frequency

c) Transmitted power

d) Relative power

2. Which of the following is not a multipath channel parameter that can be determined from power delay profile?

a) Mean excess delay

b) RMS delay spread

c) Excess delay spread

d) Doppler spread

3. The time dispersive properties of wideband multipath channel are quantified by ______ and _______

a) Mean excess delay, rms delay spread

b) Doppler spread, rms delay spread

c) Doppler spread, coherence time

d) Mean excess delay, Doppler spread

4. _______ is the square root of the second central moment of the power delay profile.

a) Mean excess delay

b) Rms delay spread

c) Excess delay spread

d) Coherence time

5. Which of the following is the first moment of the power delay profile?

a) Rms delay spread

b) Excess delay spread

c) Mean excess delay

d) Doppler spread

6. What is the order of typical values of rms delay spread in outdoor mobile radio channels?

a) Microseconds

b) Nanoseconds

c) Seconds

d) Minutes

7. Power delay profile and magnitude frequency response of a mobile radio channel are related through _______

a) Laplace Transform

b) Fourier Transform

c) S Transform

d) Wavelet Transform

8. ______ and coherence bandwidth are inversely proportional to one another.

a) Rms delay spread

b) Mean excess delay

c) Excess delay spread

d) Doppler spread

9. Coherence bandwidth is a statistical measure of range of frequencies over which channel is considered _______

a) Time dispersive

b) Frequency selective

c) Time variant

d) Flat

10. Which of the following describes time varying nature of the channel in a small scale region?

a) Delay spread and coherence time

b) Coherence bandwidth and delay spread

c) Doppler spread and coherence time

d) Delay spread and doppler spread

11. Doppler spread is a range of frequencies over which received Doppler spread is _______

a) Zero

b) Non zero

c) Infinite

d) One

12. _______ is a statistical measure of time duration over which channel impulse response is invariant.

a) Coherence time

b) Doppler spread

c) Mean excess delay

d) Rms delay spread