Research / 2022 / Article / Fig 3

Research Article

Remote Measurement of the Angular Velocity Vector Based on Vectorial Doppler Effect Using Air-Core Optical Fiber

Figure 3

Measured signals and Fourier analysis for the rotating target based on the vectorial eigenmode HE61 in air-core fiber. (a–c) Measured results for counterclockwise motion with . (d–f) Measured results for clockwise motion with Ω = −20π rad/s. (a, d) Measured Doppler intensity signals by PD1 and PD2 after filtering the DPS through two polarizers, respectively. (b, e) Calculated Fourier amplitude spectra for obtaining a Doppler shift peak. (c, f) calculated relative Fourier phase spectra between two intensity signals for obtaining the relative phase difference matching the frequency peak.