Use of continuous-wave ultrasound in tomography

Tomography is an imaging technique, which aims to obtain high quality images for the inner structure of the human body. When an object rotates around an axis with a certain velocity, each point target of this object generates a Doppler shifted signal relative to the incident signal frequency. The amplitude of this scattered signal is a function of frequency, which gives the line integral for the scatterers at a certain cross-range. The line integral information changes from position to another. Finally, the reconstructed image depends on the received signals from these projections (positions), where the brightness of any visible dot on the image depends on the strength of these returned echoes. This paper introduces a new technique for continuous-wave ultrasonic tomography, avoiding the false position and size problems of the reconstructed image. Also, the dependence of the image quality on the different parameters of the imaging system will be discussed thoroughly.