Adaptation of Turbo Punctured Codes for Hybrid-ARQ
نویسندگان
چکیده
The paper presents an iterative process of the selection of modulation and code rate in order to achieve performance close to the maximum supportable data rate of a given channel. The code rate and modulation choosing process is employed for the design of packet based hybrid-automatic repeat request (hybrid-ARQ) schemes in direct sequence code division multiple access (DS-CDMA) systems. We consider a turbo encoder with quadrature phase shift keying (QPSK) for modulation at low SNR’s and multilevel quadrature amplitude modulation (MQAM) for medium to high SNR’s, with adaptation in slow Rayleigh fading channels. The performance of the optimization is verified by computer simulation. Index Terms Hybrid-ARQ, AMC, adaptive, Rayleigh fading, diversity combining and turbo codes.
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