Hybrid ARQ schemes employing coded modulatioin and sequence combining

• Main Author: DENG, Robert H.
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 1995
• Subjects: Information Security
• Online Access: https://ink.library.smu.edu.sg/sis_research/103; http://dx.doi.org/10.1109/26.293675
• Institution: Singapore Management University

In this paper, we propose and analyze two hybrid automatic-repeat-request (ARQ) schemes employing bandwidth efficient coded modulation and coded sequence combining. In the first scheme, a trellis-coded modulation (TCM) is used to control channel noise; while in the second scheme a concatenated coded modulation is employed. The concatenated coded modulation is formed by cascading a Reed-Solomon (RS) outer code and a block coded modulation (BCM) inner code. In both schemes, the coded modulation decoder, by performing sequence combining and soft-decision maximum likelihood decoding, makes full use of the information available in all received sequences corresponding to a given information message. It is shown, by means of analysis as well as computer simulations, that both schemes are capable of providing high throughput efficiencies over a wide range of signal-to-noise ratios. The schemes are suitable for large file transfers over satellite communication links where high throughput and high reliability are required