Niko & Prabeen,
I just want to share a less technoid way to look at it 🙂
The analogy with human body is nice :
the BTS has two ears, and listen to each MS with its 2 ears.
2 ears = 2 antenna path.
The BTS will the recombine both signals, to create the highest quality possible.
This improves the UL sensitivity of the BTS a lot –> It is called “RX Diversity”.
There is also TX Diversity : ths time, the BTS has 2 mouths : same signal is sent through two different antenna paths.