Calibration system analysis of series acoustic Doppler current profiles

This paper describes the principle and composition of an acoustic simulation system which processes functional and accurate calibration of broadband ADCPs. The simulation system simulates backscatter signal that an ADCP would receive, reloads backscatter signal to ADCP by a transducer array docked with the ADCP transducer through coupling medium. According to the profiling range and current velocity information in the simulated reverberation signal, we make functional and accurate calibrations. By changing the simulating characteristic parameters in the simulation signal, we easily analyzed the functionality and performance under different characteristic parameters (depth, flow velocity, layer thickness etc) of ADCPs. Several models of self-contained direct-reading ADCPs, operating at 75kHz, 150kHz, 300kHz, and 600kHz, are used in these experiments. Research on velocity measure performance at series given speed points on different directions are carried out on these broadband ADCPs. By this mean, we can easily get the performance on maximum range and different patterns of layer width of the profilers. Based on these experiments, statistic results are also concerned in calibrating these kinds of broadband ADCPs.