Low-Complexity and High-Speed Multi-Size Circular Shifter With Benes Network Control Signal Optimization for WiMAX QC-LDPC Decoder

Benes 네트워크 제어 신호 최적화를 이용한 WiMAX QC-LDPC 복호기용 저면적/고속 Multi-Size Circular Shifter

  • Received : 2015.09.01
  • Accepted : 2015.10.05
  • Published : 2015.10.31


One of various low-density parity-check(LDPC) codes that has been adopted in many communication standards due to its error correction ability is a quasi-cyclic LDPC(QC-LDPC) code, which leads to comparable decoder complexity. One of the main blocks in the QC-LCDC code decoder is a multi-size circular shifter(MSCS) that can perform various size rotation. The MSCS can be implemented with many structures, one of which is based on Banes network. The Benes network structure can perform the normal MSCS operation efficiently, but it cannot use the properties coming from specifications like rotation sizes. This paper proposesd a scheme where the Benes network structure can use the rotation size property with the modification of the control signal generation. The proposed scheme is applied to the MSCS of IEEE 802.16e WiMAX QC-LDPC decoder to reduce the number of MUXes and the critical path delay.


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


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