[ns] How to set radio range & sensing rage of sensor nodes

[Biswa Mohan Acharya]

Hello NS guys
I m working on sensor networks. May I know how to declare/set the radio
range & sensing range of sensor node as two different values. I need these
two ranges different for my simulation. It may be a silly question but I
would like to know. If there is some file in ns2 package where I can find
such issues please let me know it.
Thanks & regards
Biswa