COHERENT DOPPLER VELOCITY MEASURING METHOD USING SIGNAL MIXING TECHNIQUE AND DEVICE THEREFOR

摘要

PURPOSE: A coherent doppler velocity measuring method and apparatus using signal mixing technique are provided to improve the efficiency of measurement by reducing measuring time or memory capacity. CONSTITUTION: A pulse repetition frequency determining unit variably determines a pulse repetition frequency based on the water depth at a desired measuring point. A signal generating unit creates a transmission signal by mixing two signals having different frequencies. A signal transmitting unit continuously transmits the created transmission signal based on the determined pulse repetition frequency. A signal receiving unit continuously receives signals scattered by underwater fine particles. A signal detecting unit removes high frequency components through filtering and detects a Doppler signal. A phase difference detecting unit detects the phase difference between pulses in the detected signal. A phase-velocity converting unit changes the detected phase difference into velocity.