Joint Time-Frequency Analysis for Removing the Spectral Interference of Terahertz
SUN Qing1, DENG Yu-qiang1*, CAO Shi-ying1, YU Jing1, LIU Feng2, WANG Chang-lei2, XING Qi-rong2
1. Optics Division, National Institute of Metrology, Beijing 100013, China 2. School of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
Abstract：Conventional Fourier-transform mixes the frequency components of the entire temporal terahertz waveform in one frequency domain; therefore, it cannot distinguish the terahertz frequency in the main pulse from the noise frequency in the pulse tail. Thus traditional Fourier-transform produces inconsistent spectra from different scanning lengths of terahertz pulse. And the interference spectrum appears when the THz echo pulse is recorded. The authors applied wavelet-transform and removed the inconsistent spectra and the interference spectra. Wavelet-transform technique exhibited the local frequency of THz in different time locations. This technique would find applications in THz time-resolved spectroscopy.
孙 青1，邓玉强1*，曹士英1，于 靖1，刘 丰2，王昌雷2，邢岐荣2. 时间-频率联合分析消除太赫兹光谱干涉[J]. 光谱学与光谱分析, 2010, 30(12): 3169-3173.
SUN Qing1, DENG Yu-qiang1*, CAO Shi-ying1, YU Jing1, LIU Feng2, WANG Chang-lei2, XING Qi-rong2 . Joint Time-Frequency Analysis for Removing the Spectral Interference of Terahertz . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(12): 3169-3173.
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