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基于频域偏的可靠和快速粗频偏移估计,用于在严重的带宽限制下连贯的DSCM系统
Optics letters
|December 13, 2024
概括
一种新的频率偏移估计 (FOE) 方法用于连贯的数字子载波复杂化 (DSCM) 系统,有效地减轻了过损坏. 这种强大的方案实现了快速而准确的频率偏移估计,即使在具有挑战性的条件下.
科学领域:
- 光学通信是指光学通信.
- 信号处理 信号处理
- 数字信号处理 数字信号处理
背景情况:
- 连贯数字子载波多重复合 (DSCM) 系统中的频率偏移 (FO) 由于带宽限制,会对子载波造成显著的过损害.
- 现有的频率偏移估计 (FOE) 方案经常在严重的过损害下降级或失败.
研究的目的:
- 为DSCM系统提出并展示一种新的FOE方案,克服现有方法的局限性.
- 为在面临严重过损害的DSCM系统中提供强大的FOE解决方案.
主要方法:
- 利用信号频谱对称性,并引入频率偏作为FO搜索的成本函数.
- 使用虚假位置 (FP) 方法进行频率转移的代计算,从而实现快速的FOE.
- 在估计过程中使用2048大小的快速里埃变换 (FFT).
主要成果:
- 在累积分布函数 (CDF) 的80%中,在三次代内实现频率偏移估计.
- 显示的最大误差小于250 MHz (4 个子载波) 和80 MHz (6 和 8 个子载波系统).
- 在不同的FO值中表现出稳定的性能,并在6个子载波系统中接收光学功率 (ROP),即使在严格的过条件下.
结论:
- 拟议的FOE方案为连贯的DSCM系统提供了一种新且有效的解决方案.
- 该方法提供了强大的性能和准确的频率偏移估计,特别是在存在强烈的过损害的情况下.
- 这一进步有助于提高高容量光通信系统的可靠性和性能.
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