• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.4
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• pp.379-386
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• 2016

Puncturing is the most common way of increasing the rate of convolutional codes. The puncturing process is done to the original code called the mother code by a specific puncturing pattern. In this article, we investigate into the question whether any convolutional code is obtainable by puncturing some (n, 1) mother codes. We present two sufficient conditions for the mother code and the puncturing pattern to satisfy in order that the punctured code is equivalent to the given (N, K) convolutional code.

• Journal of Communications and Networks
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• v.11 no.5
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• pp.455-463
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• 2009

We consider the challenges of finding good puncturing patterns for rate-compatible low-density parity-check code (LDPC) codes over additive white Gaussian noise (AWGN) channels. Puncturing is a scheme to obtain a series of higher rate codes from a lower rate mother code. It is widely used in channel coding but it causes performance is lost compared to non-punctured LDPC codes at the same rate. Previous work, considered the role of survived check nodes in puncturing patterns. Limitations, such as single survived check node assumption and simulation-based verification, were examined. This paper analyzes the performance according to the role of multiple survived check nodes and multiple dead check nodes. Based on these analyses, we propose new algorithm to find a good puncturing pattern for LDPC codes over AWGN channels.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.7A
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• pp.1074-1079
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• 1999

In this paper, the concept of puncturing is introduced to turbo code in order to implement various code as code rate varies.rates. First, several different puncturing matrices are applied into rate 1/3 encoder in order to produce various rate 1/2 turbo codes. By analyzing and comparing these results, we can show which puncturing pattern should be selected in order to maintain good performance. Second, we select some appropriate puncturing patterns which provide the best performance of turbo codes of various rates from 1/3 to 2/3 among all the possible candidates. Finally, we provide the change of required Eb/No at $P_b=10^{-4}$ as code rate varies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.4
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• pp.165-171
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• 2014

The rate of the channel code can be controlled by various methods. Puncturing is one of the methods of increasing the code rate, and the original code before puncturing is called the mother code. Any (n,k) convolutional code is obtainable by puncturing some mother codes, and the process of finding the mother code is necessary for designing the optimum channel decoder. In this paper, we proved that any (n,n-1) convolutional code has (2,1) mother codes regardless of the puncturing pattern and showed that they must be equivalent.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2002.11a
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• pp.21-24
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• 2002

본 논문에서는 광대역 무선 데이터 서비스용으로 표준화된 WLAN IEEE 802.11a Convolutional 부호기의 펑처링 패턴에 따른 성능을 분석하고, 간략화 된 구현 방법을 제시한다. 제한된 주파수 대역에서 Convolutional 부호기의 구조를 변경함이 없이 정보 전송율을 향상시키기 위해 부호기에서 출력되는 비트열을 일정한 비트 간격마다 1비트씩 생략하는 펑처링 기법이 주로 이용된다. IEEE 802.11a WLAN 채널코딩에서도 부호율이 l/2, 구속장 7인 Convolutional 부호기를 기반으로 2/3와 3/4과 같은 높은 부호율을 얻기 위해 펑처링 기법을 채택하고 있다. 본 논문에서는, 단일 하드웨어 구조를 사용해서 1/2의 기본 부호율로부터 전송율에 따라 WLAN IEEE 802.11a의 펑처링에 의한 부호율 2/3와 3/4에서, 부호기의 구조를 간략화하기 위해 펑처링 패턴 구조에 따른 부호화 성능을 조사하고 단일하드웨어 구조를 사용해서 이들 부호율의 시스템을 구현할 수 있도록 한다. 모의 실험에서는 부가 백색 가우시안 잡음 현상이 존재하는 채널을 모델링 해서, BPSK와 QPSK의 변조방법에 대해 WLAN IEEE 802.11a 펑처링 패턴에 따른 부호화 성능을 제시한다.