Photonic ADC: overcoming the bottleneck of electronic jitter
Photonic ADC: overcoming the bottleneck of electronic jitter
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DOI：
10.1364/oe.20.004454
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发表时间：
2012-02-13
期刊：
影响因子：
3.8
通讯作者：
Kaertner, Franz X.
中科院分区：
文献类型：
--
作者：
Khilo, Anatol;Spector, Steven J.;Kaertner, Franz X.
在雷达系统、软件无线电、医学成像和通信系统的应用驱动下，将宽带多ghz模拟信号精确转换为数字域一直是模数转换器（ADC）开发人员的目标。光圈抖动一直是实现更高速度和更高精度的主要瓶颈。利用锁模激光器产生的超稳定光脉冲序列进行采样的光子ADC作为克服抖动问题并将ADC性能提升到新水平的一种有前途的方法已经研究了多年。这项工作表明，光子方法可以通过使用由分立元件构建的光子ADC实现具有7.0有效位的41 GHz信号数字化，从而实现其承诺。这种精度对应于15秒的时序抖动-比目前存在的最好的电子adc性能提高4-5倍。在迈向集成光子ADC的道路上，制作了一种以光子元件为核心的硅光子芯片，并利用该芯片实现了具有3.5位有效位的10ghz信号的数字化。在这些实验中，实现了两个波长通道，提供了2.1 GSa/s的总采样率。为了证明具有更大通道数的光子adc是可能的，一个双20通道硅滤波器组已经被证明。(C)2012美国光学学会
Accurate conversion of wideband multi-GHz analog signals into the digital domain has long been a target of analog-to-digital converter (ADC) developers, driven by applications in radar systems, software radio, medical imaging, and communication systems. Aperture jitter has been a major bottleneck on the way towards higher speeds and better accuracy. Photonic ADCs, which perform sampling using ultra-stable optical pulse trains generated by mode-locked lasers, have been investigated for many years as a promising approach to overcome the jitter problem and bring ADC performance to new levels. This work demonstrates that the photonic approach can deliver on its promise by digitizing a 41 GHz signal with 7.0 effective bits using a photonic ADC built from discrete components. This accuracy corresponds to a timing jitter of 15 fs - a 4-5 times improvement over the performance of the best electronic ADCs which exist today. On the way towards an integrated photonic ADC, a silicon photonic chip with core photonic components was fabricated and used to digitize a 10 GHz signal with 3.5 effective bits. In these experiments, two wavelength channels were implemented, providing the overall sampling rate of 2.1 GSa/s. To show that photonic ADCs with larger channel counts are possible, a dual 20-channel silicon filter bank has been demonstrated. (C)2012 Optical Society of America