近年來，極化碼在第五代行動通訊(5G)應用下得到了許多關注，
2008年時由土耳其教授Erdal Arıkan首度提出通道極化的概念，2016年確定Polar Code作為5G eMBB（增強型行動寬頻通訊場景下）所使用的錯誤更正碼。
極化碼的解碼方法中最普遍使用的有順續消去法(SC)和改善前者的順續消去列表法(SCL)。由於SC解碼時是依照其順序性且下一個位元解碼時需要使用前一個位元解碼的資訊，假使前面位元解碼發生錯誤，則會造成錯誤資訊不斷傳遞；為了解決此問題SCL相較於SC則是保留了更多條路徑，但同時也造成解碼複雜度的提升。
本篇論文中主要以SC和SCL為概念結合做延伸，提出一種可適性調整列表大小解碼方法，搭配分段循環冗餘校驗(CRC)因子，稱為分段循環冗餘校驗輔助高效可適性順續消除列表法(SCA-EADSCL)，在高訊雜比中達到與分段循環冗餘校驗輔助順續消去列表法(SCA-SCL)錯誤率相近的情況下，大大的降低解碼複雜度，並且套用特殊節點快速解碼進一步降低解碼所造成的延遲。

In recent years, polar codes has gained lots of attention, with the application to the fifth generation mobile communication (5G). The concept of channel polarization was first proposed by Turkish professor Erdal Arıkan in 2008. In 2016 3GPP agreed to adopt polar codes for the eMBB (Enhanced Mobile Broadband) control channels.
The conventional decoders of polar codes are the successive-cancellation (SC) and an improvement to the SC decoder, namely, a successive-cancellation list(SCL) decoding. SC decoder is based on the order and a next bit to be decoded requires the information of the previous bits. If an error occurs in one bits, the error information will proprgate to the succeeding bits. As an improved modification from SC, the SCL decoder reserves more paths than the SC decoder to alleviate this problem of error propagation. At the same time, however, it also increases the decoding complexity.
In this work, we propose an efficient adaptive Successive-Cancellation list decoder with a segment cyclic redundancy check bits (SCA-EADSCL) by combining SC and SCL decoders. It can achieve lower decoding complexity while maintaining a similar block error rate (BLER) performance. Its BLER performance and the analysis of complexity reduction as compared to SCL, CA-SCL, SCA-SCL are also presented.

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