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arXiv · 2607.05851

Broadband microwave time-frequency analysis via stabilized period-one oscillation and recirculating frequency shifting with shared fiber loop

Xianxin Zhang·Chi Jiang·Taixia Shi·Yang Chen
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Abstract

To address the need for time-frequency analysis (TFA) of broadband microwave signals and to overcome the reliance of existing schemes on large-bandwidth swept microwave sources, we propose a broadband microwave signal TFA approach based on stabilized period-one (P1) oscillation and recirculating frequency shifting (RFS). By employing a feedback loop, a stable swept optical signal is generated from the stabilized P1 oscillation of a semiconductor laser, and its sweep bandwidth is further extended by an RFS loop to achieve multi-fold bandwidth expansion. For system compactness, the feedback loop and RFS loop share a common long fiber. The combined operation produces a broadband swept optical signal, which, through stimulated Brillouin scattering-based frequency-to-time mapping, enables TFA and frequency measurement of broadband microwave signals. Experimental results demonstrate an instantaneous analysis bandwidth of up to 57 GHz, a frequency resolution of 60 MHz, and a maximum mean absolute frequency measurement error of 38.16 MHz.

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Xianxin Zhang, Chi Jiang, Taixia Shi, Yang Chen. 2026-07-07. Broadband microwave time-frequency analysis via stabilized period-one oscillation and recirculating frequency shifting with shared fiber loop. https://arxiv.org/abs/2607.05851

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