High precision ultrasonic wave thermometer is designed by utilizing characteristic that propagation velocity of ultrasonic wave varies with temperature in medium

and use SOPC based on Nios II processor soft core as control core

design high precision ultrasonic wave thermometer.Size and cost are reduced

high frequency signal generator module

high speed signal circuit controll module

signal automatic acquisition controll module and the Nios II soft core processor module are all realized on the SOPC.Software subdivision interpolation algorithm is used for accurate measurement of transmitting time that it is proved by theory analysis and experimental verification

this method can realize measurement of ultrasonic wave transmitting time to ns level

which make the designed ultrasonic wave thermometer can realize temperature measurement

whose resolution prior to 0.001 ℃.