Journal of the Korea Institute of Information and Communication Engineering (한국정보통신학회논문지)

The Korea Institute of Information and Commucation Engineering (한국정보통신학회)
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Multi-Size Circular Shifter Based on Benes Network with High-Speed 3×3 Switch

고속 3×3 스위치를 이용한 Benes 네트워크 기반 Multi-Size Circular Shifter

  • Kang, Hyeong-Ju (School of Computer Science and Engineering, Korea University of Technology and Education)
  • Received : 2015.09.01
  • Accepted : 2015.10.19
  • Published : 2015.11.30
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Abstract

The low-density parity check(LDPC) code is being widely used due to its outperformed error-correction ability. The decoder of the quasi-cyclic LDPC(QC-LDPC) codes, a kind of LDPC codes, requires a multi-size cyclic shifter(MSCS) performing rotation of various sizes. The MSCS can be implemented with a Benes network, which requires a $3{\times}3$ switch if the number of data to be rotated is a multiple of 3. This paper proposes a control signal generation with lower complexity and a faster $3{\times}3$ switch. For the experiment, the proposed schemes are applied to the MSCS of an IEEE 802.16e WiMAX QC-LDPC code decoder. The result shows that the delay is reduced by about 8.7%.

Low-density parity-check(LDPC) 코드는 그 탁월한 에러 정정 능력으로 인해 많은 통신 표준에서 사용되고 있다. 여러 종류의 LDPC 코드 중 quasi-cyclic LDPC(QC-LDPC) 코드가 많이 사용되는데 QC-LDPC 코드의 복호기에는 여러 크기의 rotation을 수행할 수 있는 multi-size circular shifter(MSCS)가 필요하다. MSCS의 구현 방법 중 Benes 네트워크에 기반한 구조가 많이 사용되는데, rotation할 데이터의 개수가 3의 배수일 경우에는 $3{\times}3$ 스위치가 필요하다. 이 논문에서는 기존의 제어 신호 생성에 비해 복잡도가 줄어든 생성법과 기존의 $3{\times}3$ 스위치 구조 보다 더 빨리 동작할 수 있는 $3{\times}3$ 스위치 구조를 제안한다. IEEE 802.16e WiMAX 표준에서 사용되는 QC-LDPC 코드 복호기의 MSCS 에 적용하여 지연 시간을 8.7% 정도 줄이고 면적도 조금 감소시켰다.

Keywords

References

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Cited by

  1. Low-Complexity Multi-size Cyclic-Shifter for QC-LDPC Codes vol.39, pp.3, 2017, https://doi.org/10.4218/etrij.17.0116.0341
  2. Low-complexity, high-speed multi-size cyclic-shifter for quasi-cyclic LDPC decoder vol.54, pp.7, 2018, https://doi.org/10.1049/el.2017.4456