sensor network simulation

Does anybody khow about good free simulator for sensor network suimulation
I need to simulate virtual MIMO in cooperative sensor network over correlated
fading environment.

Hi

Have you considered using Matlab and Simulink?

G.L.

The best one is :
NS-2
it is free source also you can change node preference also network and data preference.
www.isi.edu/nsnam/ns/

the other is Glomosim
pcl.cs.ucla.edu/projects/glomosim