概括
这项研究提出了一种新的旋转8次方格振幅调制 (8QAM) 概率塑造方案,用于水下磁感应 (MI) 通信. 该方法提高了可靠性,并延长了通信距离,改善了信号稳定性.
科学领域:
- 水下通信系统是水下通信系统.
- 信号处理和调制技术.
- 磁感应 (MI) 通信方式
背景情况:
- 水下通信在信号可靠性和范围方面面临挑战.
- 与索引调制 (OFDM-IM) 的直角频率分割复杂化为增强数据传输提供了潜力.
- 概率造型 (PS) 技术可以优化信号星座设计,以提高性能.
研究的目的:
- 为水下MI系统引入和评估使用双模式OFDM-IM (DM-OFDM-IM) 的旋转8QAM概率造型 (PS) 方案.
- 为了提高比特错误率 (BER),并在具有挑战性的水下环境中延长通信距离.
- 评估星座旋转的有效性,以提高信号强度,防止衰减.
主要方法:
- 实现一个DM-OFDM-IM系统,具有两个不同的8QAM信号星座 (内部和外部).
- 通过将索引位映射到星座调制顺序和时间来应用概率造型,创建内部与外部信号的 3:1 比率.
- 整合星座旋转以增强雷利衰变通道中的信号弹性.
- 在15厘米水深环境中进行实验验证,距离23厘米,速度为62.18 Kb/s.
主要成果:
- 拟议的基于DM-OFDM-IM的PS旋转8QAM方案显著提高了水下MI通信中的信号可靠性.
- 星座旋转可以提高多样性,而不会增加带宽或功耗.
- 与传统的8QAM相比,该方案将通信距离延长4.6厘米,BER限值为3.8 × 10−3.
- 性能可与常数组合分布匹配 (CCDM) 相美,并增加了强度的好处.
结论:
- 拟议的旋转8QAM PS方案为短距离水下MI通信提供了高性能,低复杂性和易于实施的解决方案.
- 星座旋转是一种简单而有效的技术,用于提高水下环境中的信号可靠性.
- 这种方法代表了未来水下通信系统的有希望的进步.
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