通过对LDPC码经典的BP译码算法进行研究,针对算法译码复杂度非常大、迭代次数多、不利于硬件实现的问题,提出了一种改进的BP译码算法.改进算法通过实时监控在连续3次迭代中译码是否稳定来减少在信噪比低于译码阈值时的迭代次数.同时,在变量消息更新过程中对传递的校验信息进行数据约束,防止由于数据溢出而导致的译码失败.仿真结果表明,改进的BP算法,在性能损失不大的情况下可以有效地降低译码的复杂度,从而更利于硬件的实现.
In BP decoding algorithm of LDPC codes decoding algorithm complexity is usually very high,more iterations is not conducive to the realization of hardware.We proposed an improved BP decoding algorithm.The improved decoding algorithm for real-time monitoring through three consecutive iterations is stable to reduce the number of iterations in the decoding when the SNR is below the threshold value,at the same time the variable message updates to check information transmission constraints.Simulation results demonstrate that the improved BP algorithm,in the case of almost no performance loss,can effectively reduce the complexity of decoding,thus more conducive to the realization of the hardware.
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