不等长包的CRC约束Turbo译码

Constrained Turbo Decoding with CRC Constraint Based on Non-uniform Packetization

约束Turbo译码方法的编码方案是由Turbo码及错误检测码级联而成。该译码方法可以降低Turbo译码的复杂度,同时可以节省译码时间。遗憾的是,由于不正确包满足校验检测导致错误信息的传播,在中低信噪比时,译码性能有所降低。为了减小此类错误包的出现,文中采用不等长包构成一个长帧,在迭代之初,仅对短包进行检测,当不满足校验的短包数量小于给定值时,才对长包进行检测。仿真结果表明,文中给出的方案有效地减小了错误检测的包的数量,在中低信噪比下,译码性能也得到了提高。

Constrained Turbo - decoding method by using concatenated error detection codes with the Turbo codes can save decoding time in long frame. However, the mis - detected packets will reduce the decoding performance, especially in low- moderate SNR. In this paper, a method to reduce mis -detected packets is presented, where the frame is formed with short packets and long packets. First, only short packets are detected, and when the number of undecided short packets is lower than preset number, the long packets begin to be detected. The simulation results show the method can effectively reduce mis - detected packets and also improve the decoding performance in low -moderate SNR.