I want to make a short range rf transmitter of range 2 to 3 metre.
can anyone guide me about this.
RF modules available in the market are of range greater then 30 metre.
are there any ways to decrease range.

 

To decrease range, you decrease the transmitting power. To do that, you need to get inside the transmitter and change something. I can't see the transmitter you are using so I don't know what to change right now.