Hi Santanu, This reply is regarding hte ZOH block question You can use the 'Sample & Hold' block in the DSP blockset of simulink for this purpose (Signal Operation). You have to give a trigger to the sample and hold using clock with varing time intervals. A clock with varing time interval can be generated in many ways.. simple way is to have a switch and two separate clocks (pulse generator). If you dont have the DSP blockset. You can simply use, the 'Triggered subsystem' block. This is unber 'Subsystem' in main simulink library. Again the trigger to the block is your pulse of required time interval. Hope this helps, Bhaskar ===== --------------------------- Graduate Research Assistant ITTC, University of Kansas, Lawrence email: --------------------------- |