【摘要】：合成孔徑超聲成像作為一種超聲后處理方法,能夠?qū)⑿】讖匠上窈铣蔀榇罂讖匠上?通過逐點(diǎn)聚焦的方法,使圖像的分辨率不隨位置和深度變化。在采用同樣換能器陣元探頭的情況下,使用合成孔徑技術(shù)能夠得到更高分辨率的圖像。對(duì)于單陣元換能器來說,合成孔徑技術(shù)可以克服其在成像中出現(xiàn)的景深限制和在聚焦范圍外信噪比和橫向分辨率較低等缺點(diǎn),產(chǎn)生一個(gè)深度獨(dú)立的橫向分辨率,有效的改善單陣元換能器的成像質(zhì)量。本文重點(diǎn)研究了合成孔徑超聲成像方法,主要工作如下：(1)對(duì)合成孔徑成像算法進(jìn)行研究,并對(duì)一些常用的合成孔徑成像方法進(jìn)行了波束仿真實(shí)驗(yàn)。(2)使用Field Ⅱ仿真軟件,對(duì)聚焦型單陣元換能器和非聚焦型換能器進(jìn)行散射點(diǎn)的仿真實(shí)驗(yàn)和應(yīng)用合成孔徑聚焦算法的仿真實(shí)驗(yàn)。并通過計(jì)算各個(gè)散射點(diǎn)的橫向和軸向分辨率,來評(píng)估成像質(zhì)量。(3)使用基于FPGA開放式超聲平臺(tái),采集水平位移平臺(tái)對(duì)鎢絲線進(jìn)行掃描成像的數(shù)據(jù),并在matlab中進(jìn)行直接顯示和經(jīng)合成孔徑聚焦技術(shù)處理后進(jìn)行顯示。并對(duì)成像分辨率進(jìn)行計(jì)算更直觀的分析實(shí)驗(yàn)結(jié)果。同時(shí)對(duì)水平位移平臺(tái)采集到的離體豬小腸切片的超聲回波數(shù)據(jù),進(jìn)行顯示和對(duì)其進(jìn)行合成孔徑聚焦處理,并對(duì)其進(jìn)行比較分析。(4)使用基于FPGA開放式超聲平臺(tái),采集旋轉(zhuǎn)平臺(tái)對(duì)鎢絲線仿體進(jìn)行掃描成像的數(shù)據(jù),并在matlab中進(jìn)行直接顯示和經(jīng)合成孔徑聚焦技術(shù)處理后進(jìn)行顯示。并對(duì)實(shí)驗(yàn)結(jié)果進(jìn)行簡單的分析。(5)對(duì)超快超聲成像進(jìn)行研究,并用Field Ⅱ進(jìn)行平面波相干合成仿真實(shí)驗(yàn)。分別對(duì)多個(gè)散射點(diǎn)進(jìn)行平面波仿真實(shí)驗(yàn),和對(duì)計(jì)算機(jī)囊腫組織仿體進(jìn)行平面波的仿真實(shí)驗(yàn)。
[Abstract]:As a kind of ultrasonic post-processing method, synthetic aperture ultrasonic imaging can transform small aperture imaging into large aperture imaging. By focusing point by point, the resolution of the image does not change with the position and depth. In the case of the same transducer array element probe, a higher resolution image can be obtained by using synthetic aperture technique. For single array transducer, synthetic aperture technique can overcome the limitation of depth of field and low signal-to-noise ratio (SNR) and lateral resolution outside the focus range, and produce a depth-independent lateral resolution. The imaging quality of single element transducer is improved effectively. The main work of this paper is as follows: (1) the synthetic aperture imaging algorithm is studied. Some commonly used synthetic aperture imaging methods are simulated by beam simulation. (2) Field 鈪，

本文編號(hào)：2409525