Testing of a Diagnostic Ultrasonic Array Probe and Estimation of the Acoustic Power Using Radiation Conductance

In this paper, we describe a test method for an ultrasonic array probe using electroacoustic radiation conductance. The radiation conductance was calculated using the measured acoustic power based on the radiation force balance method and the voltage for the driving element on the probe. To illustrate the usefulness of this method, we conducted the testing with a normal as well as a faulty probe with an open element or a block gain. In the comparison of the test results from each sample, the different values of radiation conductance signified the nonuniform probe gain. Specifically, the value of the radiation conductance of nearly zero revealed a clearly faulty element. To predict the temporal averaged acoustic power from sonography, we calculated the estimated value of the temporal acoustic power of a scan beam and sonography using radiation conductance. The result showed that the uniformity of the radiation conductance of each element is a useful parameter when testing an array probe. It enables an estimation of the acoustic output without additional measurements regardless of whether or not the scanning procedure changes when creating the image.