RATE COMPATIBLE PUNCTURED TURBO-CODED HYBRID ARQ FOR OFDM SYSTEM

Now a day’s orthogonal frequency division multiplexing (OFDM) is under intense research for broadband wireless transmission because of its robustness against multipath fading. A major concern in data communication such as OFDM is to control transmission errors caused by the channel noise so that error free data can be delivered to the user. Rate compatible punctured turbo (RCPT) coded hybrid ARQ (RCPT HARQ) has been found to give improved throughput performance in a OFDM system. However the extent to which the RCPT HARQ improves the throughput performance of the OFDM system has not been fully understood. HARQ has been suggested as a means of providing high data rate and high throughput communication in next generation systems through diversity combining transmit attempts at the receiver. The combination of RCPT HARQ with OFDM provides significant bandwidth at close to capacity rates of channel. In this paper, we evaluate by computer simulations the throughput performance of RCPT code HARQ for OFDM system as compared to that of conventional OFDM