A hydrophone calibration system is a very important tool which is used to achieve precision and certainty of measurements in underwater acoustics. Hydrophones are referred to as sensors that are responsible for the detection and recording of underwater sound waves, and accordingly the method is applied in many fields including, but not limited to, oceanography, marine biology, environmental monitoring, and defense applications. In order to realize the exactness of their devises by a good calibration system it's just a must.

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A Hydrophone calibration system is a very important tool which is
used to achieve precision and certainty of measurements in underwater
acoustics.
Hydrophones are referred to as sensors that are responsible for the
detection and recording of underwater sound waves, and accordingly
the method is applied in many fields including, but not limited to,
oceanography, marine biology, environmental monitoring, and defence
applications. In order to realize the exactness of their devises by a good
calibration system it's just a must.
Hydrophone Calibration Systems

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Key Components of the Hydrophone Calibration System:
Reference Source:
The stabilization and known acoustic characteristic are the reasons for
which the source became a reference standard. This can for example
involve a speaker system that has been carefully calibrated towards the
underwater sound or a sound generator that is controlled. The source
material should equip user with a frequency range which is equivalent
to the hydrophones purpose.
Calibration Chamber:
The calibration chamber meets all necessary specifications for
hydrophone calibration as it offers a controlled environment. An
additional layer of protection is to instigate a stiff sound proof wall and
then fill it with a sound absorbing material that is as close as possible
to properties of pure water. So sensor calibration experiments are
designed to meet the rising demand for more realistic scenarios.
Signal Conditioning and Amplification:
Using best signal quality conditioning and amplification equipment is
essential to provide more accurate measurement of hydrophone signals
received. This system involves receiving, pre-amplification and
filtering of low noise to remove unnecessary noise and interferences.

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Data Acquisition System:
The intelligent data analytics system must be provided to do the job of
reading the hydrophone into the calibration acoustic signals. Our
proposed system can be designed as a high sampling rate device that
allows for transmission over a wide range of frequencies.
Types of Tests included:
 Reciprocity Test
 Comparison Test
 Transmitting Voltage Response Test up to 64 channels
 Free Field Receiving Sensitivity Test up to 64 channels
 Directivity Test for multiple frequencies
 Directivity Test with External Trigger
 Directivity Test with External Trigger for multiple frequencies
 Insulation Resistance Measurement
 Modularity & Scalability of PXIe platform
Calibration Procedure:
Baseline Measurement:
Start your test without signal and measure the hydrophone
measurement with no additional signal present. This gives the option
to calibrate during subsequent noise measurements with corresponding
background noise.

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Frequency Sweep:
Sweep done with use of reference source onto the full range span of
interest, from the lowest to the highest frequency. Sound hydrophones
at different frequencies. These data correlations provide the calibration
curves.
Amplitude Calibration:
Set calibration of the hydrophone's amplifier by reading the response
against known acoustic levels. Models should boast of the precise
mathematical apparatus to transform and treat the results of amplifier
measurements for practical applications.
Environmental Corrections:
Compensate for the environmental nuances that may arise from the
working environment conditions like temperature, pressure, and
salinity which may also affect the hydrophone's performance.
Accomplish considering correction factors that can be used to correct
the other variable.
Documentation:
Keep books of the calibration documentation which comprise the
calibration curves, correction factors, and any changes done. That
traceability and quality assurance of the including documentation are
extremely important.

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Conclusion:
Ensuring the high precision and dependability of underwater acoustic
measurement data implies the use of an efficient acoustic calibration of
hydrophones. Through adhering to diligent calibration procedures and
using cutting-edge methodology, researchers and professionals can
make certain that the hydrophones they install gives the exact data in
underwater environments of different types. Providing an acoustic
environment for science is especially important for developing the
marine sciences, as well as environmental monitoring and defence
applications that entirely depend on the accurate measurements.

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Contact us today to discuss your specific Hydrophone
Calibration System requirements
https://www.digilogicsystems.com/
Phone:
Hyderabad: (+91) 40 4547 4601 / 02 / 03
Bangalore: (+91) 80 4975 6034
Email: info@digilogicsystems.com
Location
#102, 1st Floor, DSL Abacus Tech Park Beside DSL Virtue Mall,
Uppal, Hyderabad, Telangana-500 039, India
#216, 3rd floor, Zareen Heights, Varthur Road, Nagavarapalya, C. V.
Raman Nagar, Bengaluru, Karnataka – 560093.