Secure RF Covert Communication System

To design, build, and test a RF system to enable covert communications
between two parties. The system should be full duplex and incorporate
symmetric signal encryption (16-bit).

I hope anyone out there can guide me to do about this project, I need someone to give me kick start.I have just downloaded information about radio frequency and will be doing the reading today.

If you post your schematics and current progress by now, I'm sure they will help you. Otherwise, forget it

I am just choose my title just now,but thanks that should be a good way 2 do it,thanks