一种改进的码率兼容QC-LDPC码构造算法
|
摘要
针对现有用于无人机上的QC-LDPC码的码率兼容性性能较差的问题,提出了一种改进的QC-LDPC码校验矩阵的改进构造算法。该算法首先采用PEG算法构造出具有下三角形式的高码率QC-LDPC校验矩阵的基矩阵,然后利用逆向PEG算法进行矩阵拓展,最后使用循环移位矩阵对基矩阵进行扩展,形成的校验矩阵可以兼容多个码率。该方法构造矩阵所兼容的码字的性能均近似或优于同参数下的仅使用准循环法构造的码,且硬件实现更为简单,码率控制更为灵活。
In order to solve the problem that the rate compatibility of QC-LDPC codes on UAVs,an improved adaptive algorithm for QC-LDPC based on PEG is proposed. Firstly,the base QC-LDPC parity check matrix of the highest rate with lower triangular is constructed by using the PEG algorithm. Then the inverse PEG algorithm is used to extend the base matrix. Finally,using the cyclic shift matrix to extend the base matrix. This parity check matrix can be compatible with multiple bit rates. The performance of the code based on the algorithm in this paper is better than that of the same rate code based on Quasi-Cyclic algorithm. The code based on this algorithm is much easier to implement in hardware,and it is more flexible to control the rate of this code.
In order to solve the problem that the rate compatibility of QC-LDPC codes on UAVs,an improved adaptive algorithm for QC-LDPC based on PEG is proposed. Firstly,the base QC-LDPC parity check matrix of the highest rate with lower triangular is constructed by using the PEG algorithm. Then the inverse PEG algorithm is used to extend the base matrix. Finally,using the cyclic shift matrix to extend the base matrix. This parity check matrix can be compatible with multiple bit rates. The performance of the code based on the algorithm in this paper is better than that of the same rate code based on Quasi-Cyclic algorithm. The code based on this algorithm is much easier to implement in hardware,and it is more flexible to control the rate of this code.
引文
[1]GALLAGER R G.Low-density parity-check codes[M].M.I.T.Press,1963.
[2]王琪,谢求亮,王昭诚.定码长多码率QC-LDPC码的构造[J].清华大学学报(自然科学版),2013(3):394-398.
[3]朱铁林,秦凡,李凤翔,等.应用于无人机测控传输系统的多元LDPC码[J].电讯技术,2014(12):1622-1626.
[4]LI J,NARAYANAN K R.Rate-compatible low density parity check codes for capacity-approaching ARQ scheme in packet data communications[C]//IASTED International Conference on Communications,2002:201-206.
[5]YAZDANI M R,BANIHASHEMI A H.On construction of rate-compatible low-density parity-check codes[J].Communications Letters IEEE,2004,8(3):159-161.
[6]张建斌.基于PEG算法的准循环LDPC码构造研究[J].电子器件,2012,35(6):647-651.
[7]贺鹤云.LDPC码基础与应用[M].北京:人民邮电出版社,2009.
[8]VASIC B,DJORDJEVIC I B.Quasicyclic low-density parity check codes[C]//International Conference on Telecommunications in Modern Satellite,2005:417-420.
[9]FOSSORIER M.Quasicyclic low density parity check codes[C].Proceedings in IEEE International Symposium on Information Theory,Yokohama,Japan,2003:150-151.
[10]管武,项海格.具有大码间距和大环路的QC-LDPC码的构造[J].新能源进展,2011,16(4):1-5.
[11]XIAO H,BANIHASHEMI A H.Improved progressive-edgegrowth(PEG)construction of irregular LDPC codes[C]//Global Telecommunications Conference,2004.GLOBEC,2004:489-492.
[12]HU X Y,ELEFTHERIOU E,ARNOLD D M.Regular and irregular progressive edge-growth tanner graphs[J].IEEE Transactions on Information Theory,2005,51(1):386-398.
[2]王琪,谢求亮,王昭诚.定码长多码率QC-LDPC码的构造[J].清华大学学报(自然科学版),2013(3):394-398.
[3]朱铁林,秦凡,李凤翔,等.应用于无人机测控传输系统的多元LDPC码[J].电讯技术,2014(12):1622-1626.
[4]LI J,NARAYANAN K R.Rate-compatible low density parity check codes for capacity-approaching ARQ scheme in packet data communications[C]//IASTED International Conference on Communications,2002:201-206.
[5]YAZDANI M R,BANIHASHEMI A H.On construction of rate-compatible low-density parity-check codes[J].Communications Letters IEEE,2004,8(3):159-161.
[6]张建斌.基于PEG算法的准循环LDPC码构造研究[J].电子器件,2012,35(6):647-651.
[7]贺鹤云.LDPC码基础与应用[M].北京:人民邮电出版社,2009.
[8]VASIC B,DJORDJEVIC I B.Quasicyclic low-density parity check codes[C]//International Conference on Telecommunications in Modern Satellite,2005:417-420.
[9]FOSSORIER M.Quasicyclic low density parity check codes[C].Proceedings in IEEE International Symposium on Information Theory,Yokohama,Japan,2003:150-151.
[10]管武,项海格.具有大码间距和大环路的QC-LDPC码的构造[J].新能源进展,2011,16(4):1-5.
[11]XIAO H,BANIHASHEMI A H.Improved progressive-edgegrowth(PEG)construction of irregular LDPC codes[C]//Global Telecommunications Conference,2004.GLOBEC,2004:489-492.
[12]HU X Y,ELEFTHERIOU E,ARNOLD D M.Regular and irregular progressive edge-growth tanner graphs[J].IEEE Transactions on Information Theory,2005,51(1):386-398.