Title :
High frame rate imaging using parallel transmission of focused coded fields [medical ultrasound imaging applications]
Author :
Misaridis, Thanassis ; Munk, Peter
Author_Institution :
Inst. of Commun. & Comput. Systerns, Nat. Tech. Univ. of Athens, Greece
Abstract :
We have previously presented a numerical method for calculating the excitation signals on individual elements, in order to transmit multi-focused pulsed beams in parallel. This paper shows the design of FM-coded focused fields and how these fields can yield more strongly focused fields or higher frame rate. Simulated images show the implementation of the method using only 4 emissions. Neighboring beams to be formed in parallel use different codes with a cross-correlation of 20 dB. Such a cross-correlation would be insufficient using a conventional delay-and-sum beamformer. In the proposed system, the worst-case beam interference is -46 dB, making it possible to obtain images of similar resolution to conventional imaging at very high frame rates. Additionally, coding partially compensates for the SNR loss that is due to multi-focusing using only a few emissions.
Keywords :
array signal processing; biomedical ultrasonics; correlation methods; image resolution; matched filters; modulation coding; ultrasonic focusing; SNR; coded phased array imaging; cross-correlation; element excitation signal calculation; focused coded field parallel transmission; high frame rate imaging; image resolution; matched filtering; medical ultrasound imaging; multiple-focused pulsed beams; worst-case beam interference; Concurrent computing; Delay; Focusing; Image coding; Image resolution; Interference; Matched filters; Phased arrays; Transducers; Ultrasonic imaging;
Conference_Titel :
Ultrasonics Symposium, 2004 IEEE
Print_ISBN :
0-7803-8412-1
DOI :
10.1109/ULTSYM.2004.1418065
