Novel four-beam ADCP calibration method

Abstract

The invention relates to a novel four-beam ADCP calibration method. According to the invention, a four-beam ADCP is fixed on a rotating mechanism; the rotating mechanism and a transponder array are fixed on a fixed frame; the acoustic axis direction of one transducer in the four-beam ADCP is aligned to a transmitting-receiving transducer positioned at the middle position of the transponder array;a PC controls an underwater rotating mechanism to drive the four-beam ADCP to rotate; and the acoustic axis direction of each transducer in the four-beam ADCP is aligned with the transmitting-receiving transducer in sequence. When the transmitting-receiving transducer receives signals transmitted by the ADCP transducers, sound wave signals with different frequency offsets and time delays are sentback so as to simulate flow velocities at different water layers; and the flow velocity of the four-beam ADCP can be calibrated according to the correspondence of the frequency offsets and the time delays to the flow velocities at different water layers, and the electroacoustic parameters (an emission source level, directivity and receiving sensitivity) of the four-beam ADCP transducers can be calibrated by using the transponder array.

Description

technical field [0001] The invention belongs to the technical field of calibration methods, in particular to a novel four-beam ADCP calibration method. Background technique [0002] ADCP (Acoustic Doppler Velocity Profiler) is a common instrument used to measure the velocity and flow of rivers and ocean systems at home and abroad. It is different from traditional mechanical current meters. It uses acoustic transducers to emit sound waves. Silt particles, plankton and other scatterers that flow with water produce backscattering, and the acoustic transducer receives the signal, and calculates the flow velocity by Doppler frequency shift of the received scattered acoustic signal. It has many advantages such as non-contact, automatic real-time online continuous monitoring, etc., which can greatly reduce labor intensity and increase work efficiency. [0003] The four-beam ADCP can measure the three-dimensional flow velocity of different water layers, and is widely used at home a...

AI Technical Summary

Problems solved by technology

[0003] The four-beam ADCP can measure the three-dimensional flow velocity of different water layers, and is widely used at home and abroad. The technical indicators given by the manufacturer are often the test results in a specific experimental environment, and it is difficult to calibrate it during use.

These methods have high requirements for test conditions, and the voyage test time is long and the cost is high. Therefore, it is particularly important to develop a four-beam ADCP performance calibration method that can be used in ordinary small ordinary pools.

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