“Duga”, the Steel Giant Near Chernobyl

When someone goes to Chernobyl he often misses one thing that could be of big interest and is located just a few miles away from the exploded nuclear power plant.
This one is one of the three alike built by Russian army in Russia during the iron curtain times. It was used for some of their military purposes but as you can see is abandoned now.

HERE for more photos. Does anybody know what this thing is? It looks like some sort of listening array.