The phased-array Doppler Velocity log is one of the main positioning and navigation equipment of modem ship, which has the advantages of small size of array, high precision,and without velocity compensation. As the transmitting and receiving carrier of Doppler log,the transducer needs to be tested periodically. We will face the problems of large volume and high cost if we adopt the traditional impedance analyzer.In this paper, according to the test requirements of transducer, a portable device to measure th...