一个简单的独立的三边频段THz信号生成和检测方案,基于delta-sigma调制和heterodyne检测
Optics letters
|June 13, 2025
概括
这项研究引入了一种新方法,用于使用德尔塔-西格玛调制 (DSM) 传输独立的三边带 (TSB) 太赫兹 (THz) 信号. 这种方法提高了信号质量,并在光纤系统中延长了传输距离.
科学领域:
- 特拉赫兹 (THz) 通信频率
- 光学信号处理的光学信号处理.
- 调制技术的调制技术.
背景情况:
- 高级调制格式,如正方形振幅调制 (QAM),对于增加光通信系统的数据速率至关重要.
- 高级QAM信号的直接传输可能受到噪声和能源需求的限制.
- 特拉赫兹 (THz) 频率为未来的通信系统提供了巨大的带宽潜力.
研究的目的:
- 提出和验证一种用于生成和发送独立的三边带 (TSB) 太赫兹 (THz) 信号的新方案.
- 利用德尔塔-西格玛调制 (DSM) 技术来改善高阶QAM信号的传输.
- 在防噪,光学信号与噪声比率 (OSNR) 和接收器灵敏度方面提高系统性能.
主要方法:
- 使用DSM将多边带高顺序QAM信号转换为低顺序方程相位移键 (QPSK) 信号.
- 通过标准单模光纤 (SSMF) 传输独立的TSB 256/512QAM信号.
- 通过低通波来恢复接收端信号以消除量子化噪声,从而消除了对数字对模拟转换器 (DAC) 的需求.
主要成果:
- 实现了至少2.5dB的光信号噪声比 (OSNR) 增益.
- 经过证明的接收器灵敏度增长至少为1.5dB (背靠背) 和2dB (60公里SSMF传输).
- 成功地传输和检测到独立的TSB 256/512QAM信号,其频率为320 GHz,超过60公里的SSMF,比特误差率 (BER) 低于HD-FEC值 (3.8×10−3).
结论:
- 拟议的基于DSM的方案有效地允许在THz频段中传输独立的TSB 256/512QAM信号.
- 与直接高阶QAM传输相比,该方法提供了更好的抗噪和接收器灵敏度.
- 简化接收器设计,避免DAC,有助于降低成本,并确认该方案的可行性和有效性.
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