Turbo码概率-代数联合解码算法

Turbo码采用修正的BAHL et al.算法实现解码.这是一种基于软值的概率迭代解码算法.本文在保持Turbo码迭代软解码算法优点的基础上,充分利用Turbo码编码器结构这一确知条件,结合代数解码原理,提出了一种Turbo码概率-代数联合解码算法.该算法结合了概率解码和代数解码的优点,又有效避免了误差传播的发生,使Turbo码的纠错性能在原经典算法的基础上得到进一步的提高.该算法不仅为降低Turbo码的比特误码率和误差地板值提供了一种新的研究途径,而且因其更好的纠错性能而具有十分明显的实用价值.仿真实验结果显示,在比特误码率(BER)为10^-3~10^-4时,与经典Turbo码解码算法相比,采用该算法能获得0.1dB左右的编码增益.

Joint Probability-algebra Decoding for Turbo Codes

Turbo codes conventionally adopt modified BAHL et al.algorithm,a kind of probabilitic iterative decoding algorithm based on soft values.To fully make use of the information on the deterministic structure of turbo constituent encoders according to the algebraic decoding principle in conjunction with the probabilitic decoding algorithm,this paper proposed a joint probability-algebra decoding scheme for turbo codes.Combining the advantages of iterative soft decoding and algebraic decoding and efficiently avoiding the bit error propagation,the proposed scheme is capable of further improving the error-correcting performance of turbo codes.It is not only a new research method to lower the Bit Error Rate (BER) and the error floor of turbo codes but valuable for applications as a result of better error correcting performance.Simulation results show that the turbo codes can obtain about 0.1dB asymptotic coding gain with the proposed scheme than those with the typical turbo-code decoding schemes when the BER is between 10^-3~10^-4.