Ultrasonic focusing and scanning with multiple waves
Zhang Bi-Xing (张碧星)a, Liu Dong-Dong (刘冬冬)a, Shi Fang-Fang (师芳芳)a, Hefeng Dongb
a State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China; b Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway
Abstract This paper presents a new focusing and scanning method which focuses multiple waves on a target. The key of the method is to control excitation pulses for each element of the transducer array. The excitation pulse on each array element is obtained by time reversing the signal received by the same element, which is generated by an imaginary source at the target. The excitation pulses from all array elements are transmitted and arrive at the target simultaneously, and focusing is achieved. The performance of the two methods is compared in numerical examples, and it is demonstrated that the proposed method achieves a satisfactory focusing and a good signal-to-noise ratio no matter where the target location is.
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 11174322 and 11074273) and the Research Council of Norway (Grant No. 186923/I30).
Zhang Bi-Xing (张碧星), Liu Dong-Dong (刘冬冬), Shi Fang-Fang (师芳芳), Hefeng Dong Ultrasonic focusing and scanning with multiple waves 2013 Chin. Phys. B 22 014302
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