软决策反等效器用于水下无线光通信中的OFDM系统,其信号依赖噪声和通道估计误差
Applied optics
|August 12, 2025
概括
本研究介绍了一种用于水下光通信系统的新型软决策反等效器 (SDFE). 新的等分器显著降低了比特错误率,特别是在带有频道估计错误的杂条件下.
科学领域:
- 在水下无线光学通信.
- 通信系统的信号处理.
背景情况:
- 在水下光通信中,直角频率分割复合 (OFDM) 系统面临着挑战.
- 传统的软决策反等分器 (SDFE) 不能充分解决信号非负面性,通道估计错误和信号依赖噪声 (SDN).
研究的目的:
- 为OFDM系统在水下无线光通信中开发改进的SDFE.
- 通过考虑信号非负性,频道估计错误和SDN来抑制载体间干扰 (ICI).
- 为使用SDN的OFDM系统调整轮均等框架.
主要方法:
- 纳入富里埃和逆富里埃转换成处理SDN的噪声术语.
- 导出特定的表达式,使该方法与轮式均等化兼容.
- 使用估计符号的后期时刻和未估计符号的先验时刻.
- 开发一个双向值-SDFE (BiT-SDFE) 具有可控制的逆矩阵更新和双向结构,以减少复杂性和减轻错误传播.
主要成果:
- 拟议的SDFE有效地抑制了在具有挑战性的水下环境中的载体间干扰.
- 一种与轮平框架兼容的修改方法得到了推导.
- 双向值-SDFE (BiT-SDFE) 证明了计算复杂度的降低和错误传播的缓解.
- 与现有方法相比,模拟结果显示比特错误率的性能明显优于现有方法,特别是在高噪音和严重的通道估计错误条件下.
结论:
- 拟议的SDFE,特别是BiT-SDFE,为OFDM系统在水下无线光通信中提供了卓越的性能.
- 该方法有效地解决了信号非负性,通道估计错误和信号依赖噪声所带来的复杂性.
- 这一进步对于提高水下光通信系统的可靠性和效率至关重要.
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