應用於非同調編碼調變系統之遞迴式相位同步設計

Iterative Phase Synchronization for Noncoherent Coded Modulation Systems

詹智翔(Chih-Hsiang Chan)

指導教授 ： 林茂昭

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.00591

摘要

隨著現有系統操作在低功率的情況下，turbo principle的解碼方式已成為主流，伴隨而知的同步問題逐漸越來越重要。在此論文裡，我們考慮編碼調製(coded modulation)的系統，此系統並沒有明確的提供同調相位的資訊。我們研究其演算法可針對相位的模糊(phase ambiguity)解決和估測在高斯(AWGN)通道下做模擬。
一個簡單實現的串接式(serially-concatenated)的編碼系統可利用迴旋的方式來解碼並加上相位的估測。在每次的迴旋解碼中，我們利用事後機率來估測相位，並在下一次解碼前做補償。我們將面對不同型態的相位模型做考量，並且得到不錯的錯誤率效果。

關鍵字

遞迴式 ； 相位 ； 同步

並列摘要

As communication systems operate at low signal-to-noise ratio conditions, synchronization
may become a serious problem.
In the thesis, we consider the coded modulation systems which are not explicitly
provided with the information of coherent phases. We investigate algorithms for joint
carrier phase estimation and ambiguity resolution for the AWGN channel.
An easily-implemented serially-concatenated coding system is presented that can oper-
ate with phase estimation technique which is integrated into the iterative decoding loop.
At each iteration, we use soft information from MAP decoder to estimate the carrier
phase and compensate it for the next iteration. Various phase models are taken into
consideration. We can always achieve satisfactory error performance.

並列關鍵字

iterative ； phase ； synchronization

參考文獻

[1] L. C. Steven S. Pietrobon, Gottfried Ungerboeck and D. J. Costello, Rota-

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[2] W. Liu and S. G. Wilson, Rotationally-invariant concatenated (turbo) tcm

codes," IEEE Trans. Inform.Theory, 1999.

[3] S. ten Brink., Convergence behavior of iteratively decoded parallel concatenated