Hi Shrikant,
For transmitting data via RF module you need an encoder and decoder set to be connected to RF module receiver and transmitter, such that data pin of tranmitter (RF)is connected with encoder’s output pin and that of decoder’s input pin is connected to receiver‘s (RF) data pin. Here u need to use HT-12E n HT-12D encoder decoder set for 4-bit data tranmission. The data to be transmitted is sent to encoder input pins and transmitted data will be received on decoder’s o/p pins.