A Study on Turbo Coding Systems with π/4 Shifted DQPSK Modulation
نویسندگان
چکیده
In this paper some methods of using turbo coding in conjunction with π/4 shifted Differential Quadrature Phase Shift Keying (π/4 shifted DQPSK) modulation are proposed. The models used in the simulation of the running turbo coded system and their BER performances are presented for each case. The turbo coding rate was R=1/3 and R=1/2. The MAP algorithm, 12 iterations were used. A Log Likelihood Ratio (LLR) stop criterion was selected. The interleaving length was N=1784 bits. The performances were obtained for AWGN and for flat Rayleigh fading channels.
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