YOU CAN USE THE OPNET TO SIMULATE ANY PROJECT. I SUGEST YOU TO DO THE PROJECT OVER CONTROLLING OR JAMMING THE GSM SIGNAL. ANY KIND OF SIMULATION REGARDING CDMA, GJM, WCDMA, ETC. CAN BE DONE ON THE OPNET SOFTWARE VERY EASILY.
ADNAN TANVEER
COMSATS INSTITUTE OF INFORMATION TECHNOLOGY LAHORE PAKISTAN
If you want to simulate something which is easy, then you should try to simulate any of the modulation techniques which is convenient to you, such as
ASK
PSK
QPSK
DPSK
QAM
it can be easily done in matlab.
refer to matlab help and you will find it very easy