Non-Invasive Calibration Method for Optical Switching Delay Line Based on Iterative Optimization

• DOI: 10.1109/jlt.2024.3360295
• Publication Date: 2024-01-30T18:47:53Z
• Authors: Hongsheng Niu; Shangqing Shi; Yifei Chen; Zhao Cang; Zhuang Tian; Zien Liang; Guohua Hu; Yiping Cui; Binfeng Yun
• Keywords: Line (geometry)

Optical switching delay line (OSDL) is a structure consisting of cascaded optical switches and waveguides with different lengths. Different propagation paths can be selected to obtain the desired by controlling in their "through" or "cross" states. Because its high accuracy, large bandwidth effective control, OSDL has become one key components microwave photonic beamforming system. However, calibrations states all are necessary due fabrication errors before used real applications. At present, four typical calibration methods have been demonstrated: adding power monitoring taps, variable attenuators (VOAs), phase shifters (PSs) into chip, measuring transmission spectra chip under driving voltages. additional VOAs, PSs will increase insertion loss complexity while method based on still complicated time-consuming. In this paper, non-invasive for iterative optimization proposed. Only final output port as monitor, control voltages iteratively optimized goal achieving largest extinction ratio at port. As proof concept, we calibrated 5-Bit silicon using proposed method, were measured, which good agreement those ODSL taps.