Abstract
We are developing a five-band microwave radiometer system with a single dual-polarized, rectangular waveguide antenna operating within the 1-4 GHz range and a method for retrieving the temperature profile from five radiometric brightness temperatures. We have already reported the result of a preliminary measurement experiment: accuracy 2.2℃ and precision 0.51℃ (JSMBE53). The accuracy was not enough because a clinical requirement for accuracy is 1℃ at 5 cm depth from surface (postulated center of brain). Microbubbles attached on the surface of antenna and temperature instability of the system were recognized as major causes of the error. This paper addresses (1) the measurement experiment using a phantom model that mimics the temperature profile in a brain of a newborn baby, (2) the use of bubble removal device, and (3) the improved accuracy of 0.24℃ with 1.3℃ precision.
