Buckley Brandon W, Madni Asad M, Jalali Bahram
Opt Express. 2013 Sep 9;21(18):21618-27. doi: 10.1364/OE.21.021618.
Time stretch transformation of wideband waveforms boosts the performance of analog-to-digital converters and digital signal processors by slowing down analog electrical signals before digitization. The transform is based on dispersive Fourier transformation implemented in the optical domain. A coherent receiver would be ideal for capturing the time-stretched optical signal. Coherent receivers offer improved sensitivity, allow for digital cancellation of dispersion-induced impairments and optical nonlinearities, and enable decoding of phase-modulated optical data formats. Because time-stretch uses a chirped broadband (>1 THz) optical carrier, a new coherent detection technique is required. In this paper, we introduce and demonstrate coherent time stretch transformation; a technique that combines dispersive Fourier transform with optically broadband coherent detection.
宽带波形的时间拉伸变换通过在数字化之前减慢模拟电信号来提高模数转换器和数字信号处理器的性能。该变换基于在光域中实现的色散傅里叶变换。相干接收机对于捕获时间拉伸后的光信号将是理想的。相干接收机具有更高的灵敏度，能够对色散引起的损伤和光学非线性进行数字抵消，并能够解码相位调制的光数据格式。由于时间拉伸使用啁啾宽带（>1太赫兹）光载波，因此需要一种新的相干检测技术。在本文中，我们介绍并演示了相干时间拉伸变换；一种将色散傅里叶变换与光学宽带相干检测相结合的技术。
