An amplified frequency-shifted fiber loop ringdown (FSI-FLRD) sensor is demonstrated for pressure measurement. This sensor measures pressure by monitoring the decay rate of continuous light (i.e. ringdown distance) in the fiber ringdown loop (RDL) in the spatial domain, instead of monitoring the decay rate of pulse light (i.e. ringdown time) in the time domain like traditional FLRD techniques, hence it needs neither optical pulsation nor fast electronics, improving the system cost performance. A low-noise bidirectional erbium-doped fiber amplifier (Bi-EDFA) is inserted into the RDL to compensate the intrinsic loop loss and for achieving higher detection limit. By being applied different weights on the sensing probe, the sensor detected the pressures from 0 to 5.2 MPa with a sensitivity of 0.04888 (/km MPa). The ringdown stability was 0.6%, corresponding to a detection limit of 0.04 MPa.

演示了用于压力测量的放大频移光纤环路衰减 (FSI-FLRD) 传感器。该传感器通过在空间域监测光纤振铃环路（RDL）中连续光的衰减率（即振铃距离）来测量压力，而不是像传统传感器那样在时域监测脉冲光的衰减率（即振铃时间） FLRD技术，因此它既不需要光脉动也不需要快速电子，提高了系统的性价比。将低噪声双向掺铒光纤放大器 (Bi-EDFA) 插入 RDL 以补偿固有环路损耗并实现更高的检测限。通过在传感探头上施加不同的重量，传感器可检测0至5.2 MPa的压力，灵敏度为0.04888（/ km MPa）。振铃稳定性为 0.6%，