中国激光, 2015, 42 (5): 0505001, 网络出版: 2015-05-04
光子时间拉伸模数转换系统的多通道化设计与实现
Design and Implementation of Multi-Channel Photonic Time-Stretch Analog-to-Digital Converter
光通信 模数转换器 时间拉伸 多通道化 色散 数据重构 optical communications analog-to-digital converter time-stretch multi-channel dispersion data reconstruction
摘要
光子时间拉伸模数转换(PTS-ADC)技术利用光纤中的色散效应对被采样信号进行时间拉伸和带宽压缩,可大幅提高传统模数转换器(ADC)的采样率和模拟带宽。但PTS-ADC 也存在采样时间窗口有限的缺点,难以满足连续信号的采样。采用多通道结构化设计是实现PTS-ADC 连续采样模式的有效办法,但也存在通道间的失配误差。本文优化了多通道结构设计方案,可用于产生连续光载波和实现连续模式采样的PTS-ADC 系统,并对该方案中多通道之间的偏置误差、增益误差和时间倾斜对系统的影响进行了理论分析和数值仿真。搭建了三通道实验系统平台,验证了该方案的可行性,系统采样率超过200 GSa/s、模拟带宽可达到45 GHz、有效比特位达到3.7。
Abstract
Photonic time-stretch analog-to-digital converter (PTS-ADC) system utilizes the dispersion effect of fibers to stretch the sampled analog signal in time domain and compress its bandwidth in frequency domain, which can highly improve the sampling rate and bandwidth of the traditional analog-to-digital converter (ADC). Due to the time-aperture limitation, the traditional PTS-ADC is difficult to satisfy the continuous-time signal sampling. Multi-channel architecture is adopted to achieve a PTS-ADC operating in the continuous-time mode. However, this architecture introduces the inter-channel mismatch. A multi-channel architecture is optimized so as to achieve a continuous-time PTS-ADC system with improved accuracy. The effects of inter-channel offset, gain and time mismatches are studied by numerical simulation. A three-channel experimental system with the sampling rate of more than 200 GSa/s, bandwidth of 45 GHz, and effective number of bits (ENOB) of ~3.7 is domonstrated.
钱阿权, 邹卫文, 吴龟灵, 陈建平. 光子时间拉伸模数转换系统的多通道化设计与实现[J]. 中国激光, 2015, 42(5): 0505001. Qian Aquan, Zou Weiwen, Wu Guiling, Chen Jianping. Design and Implementation of Multi-Channel Photonic Time-Stretch Analog-to-Digital Converter[J]. Chinese Journal of Lasers, 2015, 42(5): 0505001.