林茂昭臺灣大學：電信工程學研究所張正義Chang, Chen-YiChen-YiChang2007-11-272018-07-052007-11-272018-07-052006http://ntur.lib.ntu.edu.tw//handle/246246/58803Noncoherent decoding is an attractive strategy when carrier phase acquisition and tracking is difficult or impractical in communication systems. By using the powerful serial concatenated code scheme, Peleg and Marsland proposed efficient decoding methods that have good performance for noncoherent AWGN channel. In the thesis, we will consider the frequency drift induced by the mismatch of the tranceiver oscillators and modify the algorithm to achieve near coherent result based on the Peleg's method. We use a 1/2 code rate convolutional encoder and differential M-ary phase-shift keying(DMPSK) modulation to do computer simulations. The simulation results reveal the improvement of our proposed method. Further, we can also achieve near the same performance of the Peleg's method in the presence of combined frequency drift and random phase noise.Contents Abstract i 1 Introduction 1 2 Serial Concatenated Coded DMPSK System 3 2.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2 Decoder Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.2.1 Inner Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.2.2 Iterative Decoding Process . . . . . . . . . . . . . . . . . . . . 6 2.2.3 SISO Module . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3 Noncoherent Detection for DMPSK Signal 11 3.1 Noncoherent APP Decoder . . . . . . . . . . . . . . . . . . . . . . . . 11 3.1.1 Decoding Algorithm . . . . . . . . . . . . . . . . . . . . . . . 12 3.1.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 15 3.2 Discrete Trellis Decoder . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.2.1 Decoding Algorithm . . . . . . . . . . . . . . . . . . . . . . . 20 3.2.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 22 4 Iterative Decoding in the Presence of Frequency Drift 25 4.1 Decoder Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 4.1.1 Decoding Algorithm . . . . . . . . . . . . . . . . . . . . . . . 27 4.1.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 28 4.2 Detection for Combined Frequency Drift and Phase Noise . . . . . . . 30 4.2.1 Decoder Structure and Algorithm . . . . . . . . . . . . . . . . 31 4.2.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 32 5 Frequency Drift Estimation for Coded DMPSK System 37 5.1 Decision-directed Estimator . . . . . . . . . . . . . . . . . . . . . . . 37 5.1.1 Decoder Structure and Estimation Algorithm . . . . . . . . . 38 5.1.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 39 5.2 Iterative APP Estimator . . . . . . . . . . . . . . . . . . . . . . . . . 42 5.2.1 Decoder Structure and Estimation Algorithm . . . . . . . . . 43 5.2.2 Simulation Results . . . . . . . . . . . . . . . . . . . . . . . . 45 6 Conclusions 47 Bibliography 48en-US非同調解碼頻率漂移Noncoherent DecodingFrequency Driftthesis