Optical wavelength meter with machine learning enhanced precision  

作　　者：GAZI MAHAMUD HASAN MEHEDI HASAN PENG LIU MOHAMMAD RAD ERIC BERNIER TREVOR JAMES HALL 

机构地区：[1]Photonic Technology Laboratory,Advanced Research Complex,University of Ottawa,K1N 6N5 Ontario,Canada [2]Huawei Technologies Canada,Kanata,K2K 3J1 Ontario,Canada

出　　处：《Photonics Research》2023年第3期420-430,共11页光子学研究（英文版）

摘　　要：A photonic implementation of a wavelength meter typically applies an interferometer to measure the frequencydependent phase shift provided by an optical delay line.This work shows that the information to be retrieved is encoded by a vector restricted to a circular cone within a 3D Cartesian object space.The measured data belong to the image of the object space under a linear orthogonal map.Component impairments result in broken orthogonal symmetry,but the mapping remains linear.The circular cone is retained as the object space,which suggests that the conventional conic section fitting for the wavelength meter application is a premature reduction of the object space from R^(3)to R^(2).The inverse map,constructed by a learning algorithm,compensates impairments such as source intensity fluctuation and errors in delay time,coupler transmission,and photoreceiver sensitivity while being robust to noise.The simple algorithm does not require initial estimates for all parameters except for a broad bracket of the delay;further,weak nonlinearity introduced by uncertain delay can be corrected by a robust golden search algorithm.The phase-retrieval process is invariant to source power and its fluctuation.Simulations demonstrate that,to the extent that the ten parameters of the interferometer model capture all significant impairments,a precision limited only by the level of random noise is attainable.Applied to measured data collected from a fabricated Si_(3)N_(4)wavelength meter,greater than an order of magnitude improvement in precision compared with the conventional method is achieved.

关 键 词：DELAY CIRCULAR INVARIANT 

分 类 号：TP181[自动化与计算机技术—控制理论与控制工程] O43[自动化与计算机技术—控制科学与工程]