Diversity concept

Diversity definition :

The simple concept of the terms of diversity is that even if a radio signal path experiences a deep face, there will be another independent signal path available for analysis. 

The concept of diversity encompasses acceptance and respect. It means understanding that each individual is unique, recognizing for our individual differences. 

Assume that there is two antenna with some specific separation between them. Both the antenna signal are located on the same terminal. As the mobile terminal moves the antennas signal side experience different fading levels.

The received signal level varies with their corresponding fading levels. Hence we need to select an antenna that has a higher signal level. This is done so that the probability of deep fading is to be avoided.

There are two kinds of diversity :
  • Microscopic diversity
  • Macroscopic diversity
1. Microscopic diversity :

The counteract small signal fading in the signal received under very small distance, microscopic, diversity can be used to exploit changing signal.

It can prevent the small signal fades in case of fewer antenna separations if two antennas are used.

By choosing the signal of higher strength most of the time, the receiver can reduce the fading effects.

2. Macroscopic diversity :

The signal strength is too much decreases in large scale fading because of the problems related to shadowing by selecting a base station that is not shadowed in comparison to the other base stations, the mobile unit in its forward path can get a better signal to noise ratio (SNR).

Such a diversity concept is used to decreases the large scale signal fades is called macroscopic diversity. At the base station receiver is to end, this diversity method is useful.