利用数字喷泉编码可有效提高多跳中继传输的效率. 提出一种基于数字喷泉码的中继多跳传输机制，从两方面改善中继转发性能：每两个中继组成中继对，采用旋转星座调制技术获得信号空间分集增益，但不降低信道的频谱效率；根据改进的合并算法对中继转发的喷泉编码数据包进行线性组合，获得数据包分集效果，提高信道利用率，缩短传输时间. 仿真结果显示，实现数据包分集和信号空间分集后，多跳中继传输效率显著提高，传输时间有所缩短.
In multi-hop relay transmission, digital fountain codes can greatly improve transmission efficiency. A multi-hop relay transmission scheme based on fountain codes is proposed, which improves data relay performance in two ways: 1) Two relay nodes form a relay pair, and by using rotated constellation modulation,
signal space diversity gain is obtained without sacrificing bandwidth efficiency. 2) An improved encoded packets linear combination algorithm is used to rebuild the encoded packets by the relay to realize packet diversity. Simulation results show that transmission efficiency of the multi-hop relay transmission is improved considerably, and transmission time reduced.
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