Optimum Combination of AMC and ARQ with Imperfect CSI

توضیح سیویلیکا: 39244 .] A new scheme is presented for reliable and error-freecommunication, using optimized combination of adaptivemodulation and coding (AMC) and automatic repeat request(ARQ). Using conventional coding a limited value of error remainswhich to eliminate it, infinite transmission power or codewordlength is required. As this is impossible in practical systems, ARQis utilized. The function of ARQ is to remove residual error inwhich error detection codes are used and retransmission isrequested upon error detection. However If the error correctioncapability is weak the number of retransmission will increasewhich decreases throughput on the hand high error correctioncapability requirements long block codes and high transmissionpower which is limited by average power constraint. In this articlea method for optimum combination of error correction codes inlink adaptation and ARQ is provided. Another practicalconstraint which is considered is that due to estimation errorperfect CSI is not available and this restrict link adaptation tosatisfy the target BER constraint. A new technique is presented inthis paper for adaptive modulation and coding based on imperfectCSI. Numerical evaluations indicate the functionality of theproposed design.

Keywords:

Link adaptation , Adaptive Modulation and Coding , Automatic repeat request , Imperfect CSI