Primary level ultrasonic power measurement by radiation force balance (RFB) developed at National Institute of Standards (NIS) - Egypt

摘要

Medical ultrasonic is widely used in several medical applications for both diagnostic and physiotherapy as a result of its non-invasive and non-ionizing nature. The output power level of ultrasonic radiation must be well-known for both human being safety considerations and performance assessment of employed equipment. Before this work there was no primary level ultrasonic power measurements system to be used as a reference standard in Egypt, therefore, ultrasonic power measurement system based on the radiation force balance method (RFB) is developed and realized in the National Institute of Standards (NIS) in Egypt. NIS is the Egyptian National Metrology Institute (NMI) that is responsible to develop and offer such kind of measurement and calibration services, The system was developed according to the IEC Standard 61161 (Arrangement E), to measure power values in the range from 10mW to 15 W, at operating frequencies between 1.8 MHz and 15 MHz with less than 7% uncertainty. The system was calibrated against an ultrasound reference standard source received from the Korean Research Institute of Standards and Science (KRISS). The measurements were analyzed and presented in this work. The NIS system measurement results are within the accepted and internationally recognized uncertainty and measurement capabilities range.