An experimental measurement of simple chip AD8302 implemented in SONAR interferometer

The paper investigates the underwater acoustic signal DOA (Direction Of Arrival) estimation of the passive sonar interferometer using the combination of the phase and amplitude comparison. Therefore, we performed an experimental measurement in this research for the AD8302, which was applied in the sonar interferometer to estimate DOA of the acoustic signals. The proposed system was designed and established for the experimental measurement in the scale of the lab water tank. The acoustic signal, which was used for the measurement, has pulsed-shape waveform with carrier frequency 200 kHz. The measurement results show that: the proposed sonar interferometer using the AD8302 could estimate the DOA of the signal with high accuracy and resolution. Specifically, for the real DOA = -1°, 0° and 1.5°, the sonar interferometer estimated the DOA = -0.9°, 0° and 1.37°. The root mean square error (RMSE) of the phase difference are 3.5°, 2.9° and 2.3° and the RMSE of the DOA estimation 0.04°, 0.03° and 0.02° for the real DOA = -1°, 0° and 1.5°, respectively.