Compact Photonics-Assisted Short-Time Fourier Transform for Real-Time Spectral Analysis

• DOI: 10.1109/jlt.2023.3307680
• Publication Date: 2023-08-23T18:00:09Z
• Authors: Wenhao Dong; Xiaoyu Chen; Xuhua Cao; Zexuan Kong; Lu Wang; Guangyi Li; Ming Li; Ninghua Zhu; Wei Li
• Keywords: Chirp; Window function; Center frequency

A compact photonics-assisted scheme for short-time Fourier transform (STFT) is proposed and experimentally demonstrated. In the scheme, a periodic chirp signal an electrical bandpass filter (BPF) are applied to achieve sliding window function. At same time, BPF utilized realize frequency-to-time mapping obtain frequency-domain information in each time window. The STFT can be realized by splicing corresponding different windows into two-dimensional time-frequency graph. Experimentally, STFTs of various time-varying microwave signals demonstrated, where frequency resolution 100 MHz, 0.1 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> s, real-time measurement range from 1 9.7 GHz separately realized. addition, only limited bandwidth center BPF. Furthermore, avoids additional processing latency compared dispersion-based schemes, which ensures great performance.