基于带宽有限的蓝色LED的OFDM-UOWC系统中的非线性缓解,使用差异预强调
Applied optics
|November 27, 2024
概括
一个新的差分预强调 (DPE) 方案有效地对抗基于蓝色发光二极管 (LED) 的水下光学无线通信 (UOWC) 的非线性扭曲. 这种方法显著提高了对各种调制格式的比特错误率 (BER) 性能.
科学领域:
- 光学无线通信的无线通信
- 信号处理 信号处理
背景情况:
- 基于蓝色发光二极管 (LED) 的水下光学无线通信 (UOWC) 由于LED带宽有限而面临非线性扭曲,阻碍了性能.
- 直流偏向光学直角频率分割复杂化 (DCO-OFDM) 是UOWC的一个常见技术,但易受这些非线性影响.
研究的目的:
- 提出和实验验证一个差分预强调 (DPE) 方案,以减轻DCO-OFDM系统中LED调制带宽引起的非线性.
- 为不同的调制格式和符号速率优化DPE方案,以提高传输性能.
主要方法:
- 实施和实验验证OFDM信号传输的差分预强调 (DPE) 方案.
- 在各种符号速率上进行了四度相位移键 (QPSK),16度四度幅调制 (16-QAM) 和64度四度幅调制 (64-QAM) 的数值模拟.
- 实验验证是在2.5米的自来水UOWC设置中使用8MHz蓝色LED发射器进行的.
主要成果:
- 发现最佳DPE值可以缩短信号上升/下降时间,并防止超/低射.
- 模拟和实验表明DPE方案显著提高了比特错误率 (BER) 的性能,实现了超过4个级别的改进.
- 优化的调制格式和符号率依赖的DPE因子被确定为最低BER.
结论:
- 差分预强调 (DPE) 方案是缓解蓝色LED型UOWC系统非线性的一种有效方法.
- 该DPE方案能够在各种道条件下成功传输高数据速率 (高达72.28Mb/s),包括流.
- 该研究强调了基于调制格式和符号率优化DPE因子的重要性,以获得优越的UOWC性能.
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