盧比轉換代碼主要是針對近來網路越來越發達以及廣播系統愈增廣泛使用,為了因應各個使用者不同的通道環境都能夠切確的的解碼成功所設計的一套編碼方法, 其屬無率碼的一種, 碼率視各個通道狀況不同而定, 故能有效的利用每個碼位元, 而猛禽碼是用一個外碼來改善盧比轉換代碼會造成的錯誤地板, 能在較低的碼率就解碼成功。而這篇論文主要是針對上述的兩種無率碼所提出不同的解碼方式以期可以在較低的碼率就解碼成功。又由於部分誤碼性能之間的權衡,解碼複雜性和無率碼的編碼率, 組合增量解碼和知情的動態調度, 被稱為知情的動態調度的增量解碼, 對二元對稱通道是一個有吸引力的解決方案。然而, 應用知情的動態調度的增量解碼在可加性白雜訊高斯通道可能會導致一種降解的錯誤率性能。在逐步接收符號在可加性白雜訊高斯通道可能不會立即利用在解碼過程導演知情的動態調度, 這違反了基本理念無率碼。另一方面, 一個停止準則相結合與知情的動態調度可能導致當前解碼試圖終止太早, 和信道信息包含在最初收到的碼字不會得到有效利用。在此提出了一種新的動態解碼調度策略建議。在建議解碼器, 新的接收符號, 可立即使用的解碼過程。對於盧比變換代碼和猛禽碼一個多可加性白雜訊高斯通道, 該算法提供了更平衡折衷。在猛禽碼, 誤碼率性能有明顯提高。

As part of the tradeoff between error performance, decoding complexity
and the overhead of rateless codes, the combination of incremental decoding
(ID) and informed dynamic scheduling (IDS), known as IDIDS, is an attractive
solution in binary symmetric channel (BSC). However, applying IDIDS
in an AWGN channel may cause a degradation in BER performance. The
incrementally received symbols from the AWGN channel may not be immediately
utilized in the decoding process directed by IDS, which violates the
basic idea of rateless codes. On the other hand, a stopping criterion combined
with IDS may cause the current decoding attempt to terminate too early, and
the channel information contained in the originally received codeword will
not be used efficiently. In this paper, a new dynamic decoding schedule strategy
is proposed. In the proposed decoder, the new received symbols can be
immediately utilized in the decoding process. For Luby transform (LT) codes
and Raptor codes over an AWGN channel, the proposed algorithm provides
a more balanced tradeoff. In the case of Raptor codes, the BER performance
is obviously improved.

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