Signal processing in scanning thermoacoustic tomography in biological tissues.
Microwave-induced thermoacoustic tomography was explored to image biological tissues. Short microwave pulses irradiated tissues to generate acoustic waves by thermoelastic expansion. The microwave-induced thermoacoustic waves were detected with a focused ultrasonic transducer to obtain two-dimensional tomographic images of biological tissues. The dependence of the axial and the lateral resolutions on the spectra of the signals was studied. A reshaping filter was applied to the temporal piezoelectric signals from the transducer to increase the weight of the high-frequency components, which improved the lateral resolution, and to broaden the spectrum of the signal, which enhanced the axial resolution. A numerical simulation validated our signal-processing approach.
Xu
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Optical Imaging Laboratory, Texas A&M University, College Station 77843-3120, USA.
Wang
L V
LV
D000162:Acoustics; D000818:Animals; D002645:Chickens; D006358:Hot Temperature; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008872:Microwaves; D015233:Models, Statistical; D009132:Muscles / Q000473:pathology; D013997:Time Factors; D014054:Tomography / Q000295:instrumentation* / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation