Browsing by Author "Unal, Canberk"

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Citation - WoS: 2
Citation - Scopus: 3
94.8 Km-Range Direct Detection Fiber Optic Distributed Acoustic Sensor
(Institute of Electrical and Electronics Engineers Inc., 2019) Uyar, Faruk; Onat, Talha; Unal, Canberk; Kartaloǧlu, Tolga; Ozdur, Ibrahim T.; Özbay, Ekmel
This work demonstrates an ultra-long range direct detection fiber optic distributed acoustic sensor which can detect vibrations at a distance of 94.8 km with 10 m resolution along the sensing fiber. © 2019 Elsevier B.V., All rights reserved.
Citation - WoS: 17
Citation - Scopus: 27
A Direct Detection Fiber Optic Distributed Acoustic Sensor With a Mean SNR of 7.3 dB at 102.7 Km
(IEEE-Inst Electrical Electronics Engineers Inc, 2019) Uyar, Faruk; Onat, Talha; Unal, Canberk; Kertelog, Tolga; Ozbay, Ekmel; Ozdur, Ibrahim
In this work, we present the experimental results of a direct detection phi-OTDR based distributed acoustic sensor system. The system uses two cascaded acousto-optic modulators in order to generate optical pulses with very high extinction ratio and dual photodetector scheme for high dynamic range. The proposed schemes are investigated in detail and their performance enhancement is experimentally verified. Four piezoelectric based fiber stretchers are placed on a similar to 104 km single-mode test fiber at the distances of 1 km, 10 km, 87 km and 102.7 km and used for perturbation tests. The stretchers generated vibration signals which are analyzed to quantify the system performance. The signal-to-noise ratio (SNR) of vibration signals at the monitored distances is measured over the 12-hour recorded data within 34-second time windows considering the multi-point random interference of scattered light and fading phenomena. Using the 12-hour data, SNR histograms at four different locations are generated and mean SNR values are obtained. The signals received from 102.7 km has a maximum SNR of 24.7 dB and a mean SNR of 7.3 dB with a spatial resolution of 15 m. To the best of our knowledge, this is the highest-range reported direct detection phi-OTDR based distributed acoustic sensor system.
A Simple Method for Enhancing the SNR in Direct Detection (p-OTDR Based Distributed Acoustic Sensors)
(IEEE, 2020) Uyar, Faruk; Kartaloglu, Tolga; Unal, Canberk; Ozbay, Ekmel; Ozdur, Ibrahim
A simple and effective method for increasing the SNR and range in fp-OTDR based direct -detection distributed acoustic sensors is proposed and experimentally verified. The proposed method results in 11 dB SNR improvement at 66 km. (fD 2020 The Author(s)