The invention discloses an FPGA-based
sound wave multiple reflection
sediment concentration measurement method. The method comprises the following steps: constructing an ultrasonic
underwater measurement
system capable of realizing ultrasonic multiple reflection and driving the ultrasonic
underwater measurement
system to work; an ultrasonic
transducer is driven by the FPGA to emit ultrasonic
waves; echo signals of the ultrasonic
waves passing through the turbid liquid are collected, subjected to analog-to-
digital conversion and then transmitted to the FPGA; digital filtering and
peak detection are carried out on the echo data based on the FPGA; according to a
peak value detection result, an
ultrasonic attenuation coefficient is calculated based on the FPGA in combination with numerical integration; for a plurality of turbid liquid bodies of the same type with known
sediment concentrations, the second step to the fifth step are executed respectively,
ultrasonic attenuation coefficients under different concentrations are obtained, and then fitting is conducted on the
ultrasonic attenuation coefficients and the concentrations to obtain a regression equation of the attenuation coefficients and the
sediment concentrations; and executing the second step to the sixth step to obtain an ultrasonic
attenuation coefficient aiming at a to-be-detected turbid liquid body, and substituting the ultrasonic
attenuation coefficient into the regression equation to obtain the
sediment concentration of the to-be-detected turbid liquid body. According to the method, the defects of the traditional method in real-time performance and precision are overcome, and the real-time performance and accuracy of
sediment concentration measurement are remarkably improved.