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

  • Received : 2015.09.01
  • Accepted : 2015.10.19
  • Published : 2015.11.30


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%.


cyclic-shifter;multi-size circular shifter;LDPC decoder;QC-LDPC decoder


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