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EDFA for distributed acoustic sensing

The main function of EDFA for distributed acoustic sensing is to amplify the pulsed light after AOM modulation. Usually in distributed acoustic sensing system, we choose 20mW narrow linewidth continuous light laser, and then modulate the continuous light through AOM to modulate the pulse light. So the optical power of the pulsed light after AOM modulation is basically around -30dbm. This optical power is small, if directly into the fiber optic cable will only be able to transmit a very short distance, or even can not be used.

Gain of EDFA

A pulsed EDFA for distributed acoustic sensing needs to achieve a gain of 12db. With a 12db EDFA, by amplifying the pulsed light output from the AOM and feeding it into the fiber optic cable, monitoring over 30km can basically be achieved through coherent detection

Pulse EDFA and Small Signal EDFA

There are 2 types of EDFAs commonly found in distributed acoustic sensing systems, a pulsed EDFA and a small-signal EDFA. The pulsed EDFA is mainly used to amplify the output pulsed light from the AOM. The small-signal EDFA is generally used to amplify the returned Rayleigh-scattered light (usually placed at the front end of the detector, so it is also called with pre-amplified EDFA). Usually, if the parameters of the balanced photodetector are properly selected, we can usually not use the pre-amplified EDFA.

Control software for EDFA

Distributed acoustic sensing EDFA internal will use 980 pump laser and erbium-doped fiber, when the EDFA module production is completed, the length of the erbium-doped fiber that is determined that can not be dynamically modified, and we want to change the gain of the EDFA, we can adjust the size of the optical power of the EDFA through the software. We can through the EDFA control software is very convenient to modify the EDFA current value, so that the 980 pump laser output optical power strength and realize dynamic adjustment.

EDFA Products for Distributed Acoustic Sensing

Pulsed EDFA erbium-doped fiber amplifier, C-band, commonly used after the acousto-optic modulator to achieve the amplification of pulsed optical signals, common in distributed fiber optic sensing systems, LIDAR and other applications.
Pulsed EDFA Erbium-doped fiber amplifier Pulsed signal amplification C-band

Pulsed EDFA erbium-doped fiber amplifier, C-band, commonly used after the acousto-optic modulator to achieve the amplification of pulsed optical signals, common in distributed fiber optic sensing systems, LIDAR and other applications.

Small signal EDFA erbium-doped fiber amplifier is used to amplify weak light signals or as a preamplifier for weak light detection, and is widely used in fiber optic sensing systems and fiber optic communication network systems.
Small signal erbium-doped fiber amplifier EDFA pre-amplification C-band

Small signal EDFA erbium-doped fiber amplifier is used to amplify weak light signals or as a preamplifier for weak light detection, and is widely used in fiber optic sensing systems and fiber optic communication network systems.