Realization of transmit and receive focusing with limited-diffraction beam using linear transducer in B-mode ultrasound imaging system

The transmit pulse waveforms of a limited-diffraction beam in a linear array transducer should be varied depending on the transducer element location, the realization of which requires complicated hardware. In order to overcome this disadvantage while achieving the same field response, we propose a method of synthesizing limited-diffraction beams by the combined signal processing of plane waves that propagate in distinct directions over several consecutive insonification time intervals. This method is capable of achieving both higher transmit power and better lateral resolution within a larger field of depth. From simulation and experimental results, we call clearly observe its superiority in terms of the mainlobe width and field of depth.