Why are there 2 RWR arrays on this aircraft?

Extremely curious as to why there are 2 RWR arrays on the vertical stabiliser of this MBB-339CM as opposed to only 1 on the Hawk? Is it to provide 360 coverage? And does anyone know why the arrays on these 2 aircraft are much bigger than the arrays on other aircraft, has it got to do with being technologically older? Also, does anyone have a clue as to where the RWR arrays are located on this Su-30MKM?