LDPC Codes對WiMAX接取管理影響之研究

Research of LDPC Codes Access Management Influence in WiMAX

石千碁(Chian-Chi Shih)

指導教授 ： 蔡佳勝

大同大學/電機資訊學院/資訊工程學系所/碩士(2009年)

摘要

最近,除了傳統的混合式自動重送請求(HARQ)之外，可靠度的混合式自動重送請求(RB-HARQ)也是備受大家矚目，可靠度的混合式自動重送請求的更正錯誤機制是利用軟式輸-入軟式輸出(SISO)解碼方式，可以根據軟式輸出的結果來選擇傳送不可靠的位元做重送，而另一項研究是根據不規則的低密度同位元檢查碼(LDPC codes)有不同的階數(Degree)，而在階數不同的情形下，在解碼的過程中會影響結果的錯誤率。低密度同位元檢查碼在近年來也是非常受通訊系統重視，在IEEE802.16e, DVB-S2 和 802.11n之中都有所使用，然而在IEEE802.16e的系統中，低密度同位元檢查碼的混合式自動重送請求只能使用Chase合併方法，所以在這篇論文中我們研究其他的混合式自動重送請求使用在IEEE802.16e的低密度同位元檢查碼中，分析及探討其結果。

關鍵字

混合式自動重傳請求 ； 低密度同位檢查碼 ； 全球互通微波存取

並列摘要

Recently, Hybrid Automatic Repeat request (HARQ) is a powerful scheme in communication system. In this paper, we study the Reliability-Based Hybrid ARQ (RB-HARQ) which is a new attractive ARQ scheme with Low-Density Parity-Check (LDPC) codes. The RB-HARQ can use soft-input soft-output (SISO) decoding scheme, the retransmission bits are selected at receiver based on the bit reliability. The other research the nodes of irregular LDPC code have the reliability to correct with degree distribution. LDPC code is an error control coding and popular in communication system which in IEEE802.16e, DVB-S2 and 802.11n are used. However the HARQ scheme of LDPC codes in IEEE802.16e channel coding only can use the chase combining, so we study the RB-HARQ scheme using LDPC codes in IEEE802.16e.

並列關鍵字

wimax ； ldpc ； harq

參考文獻

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