联合正交调制与网络编码的协作HARQ方案

Joint quadrature modulation and network coding for cooperative Hybrid-ARQ

为了提高正交调制协作系统的传输效率,提出联合网络编码与正交调制协作混合自动重传请求方案。所提方案在重传中引入了网络编码,使得系统可以在相同的时间内能够重传更多的信息,从而节约了重传时间,进而改善系统吞吐量。接着,建立了Markov状态转移模型,并推导了所提方案在各种脉冲幅度调制(PAM)方式下的误帧率和延时性能,进而获得其吞吐量闭式近似解。仿真结果表明,与传统正交调制协作HARQ方案相比,所提方案在信噪比为5 dB、10 dB、15 dB处分别采用2PAM、4PAM、8PAM调制时都有近8%的吞吐量增益。

In order to improve the transmission efficiency of quadrature modulated cooperative diversity system, the joint network coding and quadrature modulated scheme for cooperative hybrid automatic repeat request （NCQMHARQ） was proposed. By introducing network coding in the retransmission, this scheme could retransmit more information at the same time, thus the retransmission time was saved, resulting in the improvement of the throughput. Furthermore, based on the system＇s Markov state transition model, the frame error rate （FER） and delay performance in the modulation of Mary pulse amplitude modulation （PAM）were investigated, therefore the closed approximate solution of the throughput was acquired. Simulation results show that, the proposed scheme outperforms the traditional quadrature modulated coop erative diversity system HARQ scheme by a throughput gain of approximate 8% in the following scenes： 2PAM modula tion at 5dB SNR, 4PAM at 10dB and 8PAM at 15dB.