Microwave induced thermo-acoustic tomography (MITAT) is a developing technique for biomedical applications, especially for early breast cancer detection. In this paper, impacts of short microwave pulse on thermo-acoustic (TA) signals are analyzed and verified through some experimental comparisons. In these experiments, short microwave pulses with widths of 10 ns and 500 ns are employed as radiation resources. TA signals generated from a cubic sample are analyzed in both time- and frequency-domain. A trapezoid sample is also performed for experimental comparing. Different from previous literature, the effects of rising edge of radiation microwave pulse have been intensively studied. Experimental results demonstrate that shorter rising edge duration conducts broader bandwidth of TA signal, which give rise to better spatial resolution for tomography imaging.
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