Low-Complexity Multi-Size Circular Shifter for QC-LDPC Decoder Based on Two Serial Barrel-Rotators

두 개의 직렬 Barrel-Rotator를 이용한 QC-LDPC 복호기용 저면적 Multi-Size Circular Shifter

  • Received : 2015.07.02
  • Accepted : 2015.08.06
  • Published : 2015.08.31


The low-density parity-check(LDPC) code has been adopted in many communication standards due to its error correcting performance, and the quasi-cyclic LDPC(QC-LDPC) is widely used because of implementation easiness. In the QC-LDPC decoder, a cyclic-shifter is required to rotate data in various sizes. This kind of cyclic-shifters are called multi-size circular shifter(MSCS), and this paper proposes a low-complexity structure for MSCS. In the conventional serially-placed two barrel-rotators, the unnecessary multiplexers are revealed and removed, leading to low-complexity. The experimental results show that the area is reduced by about 12%.


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


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