A method of rate matching process of the hybrid Automatic Repeat reQuestion (HARQ) operation in which coded bits are selected for a transmission depends on whether the transmission is a first transmission of a new packet or a retransmission of an existing packet. In downlink of long term evolution (LTE) system, a downlink grant message is transmitted along with the packet data transmission. The grant message may also contain the redundancy version (RV). A new data indicator (NDI) is introduced to indicate the start of a new packet. The improved method of rate matching may be implanted into either a transmitter or a receiver.