WIreless Communication-21/09/23

If the system is designed with the usage of hexagonal-shaped cells, how are the base-stations located?    

• A.At the centre of cell    
  
  

• B.At the edge of cell    

• C.At the corner of the cell    

• D.All of the above    

Which effect is widespread in adjacent-channel interference especially after the reception of a weak signal by a mobile user from the base-station?    

• A.Near-far effect    
  
  

• B.Doppler’s effect    

• C.Capture effect    

• D.Kendall effect    

Which antennas are used at the center of the cells for the    

• Omni-directional antenna    

• Sectored directional antennas    

• Both A and B    

• None of the above    

Co-channel reuse ratio (Q) is    

• 3√N    

• .√3N    

• √3 ( N)    

• N√3    

The propagation model that estimates radio coverage of transmitter is called    

• Large scale propagation model    

• Small scale propagation model    

• Fading Model    

• Okumura Model  

The speed of radio wave in free space is

• 1. 3 x 10⁶ metres/second

• 1. 3 x 10⁸ metres/second

• 1. 3 x 10⁶ miles/second

• 1. 3 x 10⁸ miles/second

Radio waves sometimes bend around the corners due to

• 1. Reflection

• 1. Diffusion

• 1. Refraction

• 1. Diffraction

Which of the following is the phenomenon caused when Radio waves travel in two or more paths during propagation and produce slowly-changing phase differences between signals?

• 1. Absorption

• 1. Fading

• 1. Baffling

• 1. skip

Coherence bandwidth is

•   Channel that passes all spectral components with

•    The bandwidth of modulated signal

•    Channel that passes all spectral components with linear phase

•   Both a and c

The techniques used for small scale multipath measurements are

1. Direct RF pulse system
2. Spread spectrum sliding correlator channel sounding
3. Frequency domain channel sounding

•    1 and 2 are cor

•    1 and 3 are correct

•    2 and 3 are correct

• All the three are correct