基于多幅图像融合的合成孔径技术在发射和接收过程中均能够实现动态聚焦，所以具有较高的图像分辨率。但是，基于多幅图像融合的合成孔径技术对系统的数据处理、传输、存储能力等有很高的要求，因此难以应用于实际系统中。针对该问题，提出了快速合成孔径技术。该技术利用定点聚焦法取得扫描线数据，再结合基于多幅图像融合的合成孔径技术中的相干样点叠加方法，从而得到高分辨率图像。提出的快速合成孔径技术实现了发射和接收的动态聚焦，并且在一定范围内使分辨率与成像范围无关。利用软件FieldⅡ进行仿真分析，通过与最小方差(MV)法以及基于多幅图像融合的合成孔径技术的比较，验证了快速合成孔径技术的可行性。

The synthetic aperture (SA) imaging based on multi-images fusion is dynamically focused in both transinission and receiving yielding an improvement in resolution. But this imaging technique sets high demands on processing capabilities, data transport and storage. It also makes the implementation of a SA system very challenging and costly. The proposed method is specifically for this issue. The method uses the focused image lines as input data, and takes advantage of the synthetic aperture imaging based on multi-images fusion which picks out the coherent samples of the recorded echoes and sums these samples, thus obtaining a high resolution image. The proposed method is dynamically focused in both transmission and receiving, and a range independent lateral resolution is obtained. With Field II software, simulations on scatters and phantom are made and compared with broadband minimum variance (MV) beamforming and SA imaging based on multi-images fusion, the feasibility of the method named a fast synthetic aperture (FSA) imaging is verified.