Nguyen H C, Hayes-Gill B R, Morgan S P, Zhu Y, Boggett D, Huang X, Potter M
Electrical Systems and Optics Research Division, Faculty of Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
J Med Eng Technol. 2010 Jul-Aug;34(5-6):306-15. doi: 10.3109/03091902.2010.481032.
This paper presents a general embedded processing system implemented in a field-programmable gate array providing high frame rate and high accuracy for a laser Doppler blood flow imaging system. The proposed system can achieve a basic frame rate of flow images at 1 frame/second for 256 x 256 images with 1024 fast Fourier transform (FFT) points used in the processing algorithm. Mixed fixed-floating point calculations are utilized to achieve high accuracy but with a reasonable resource usage. The implementation has a root mean square deviation of the relative difference in flow values below 0.1% when compared with a double-precision floating point implementation. The system can contain from one or more processing units to obtain the required frame rate and accuracy. The performance of the system is significantly higher than other methods reported to date. Furthermore, a dedicated field-programmable gate array (FPGA) board has been designed to test the proposed processing system. The board is linked with a laser line scanning system, which uses a 64 x 1 photodetector array. Test results with various operating parameters show that the performance of the new system is better, in terms of noise and imaging speed, than has been previously achieved.
本文介绍了一种在现场可编程门阵列中实现的通用嵌入式处理系统，该系统为激光多普勒血流成像系统提供高帧率和高精度。所提出的系统对于256×256图像，在处理算法中使用1024点快速傅里叶变换（FFT）时，可实现血流图像的基本帧率为1帧/秒。利用混合定点-浮点计算来实现高精度，同时合理使用资源。与双精度浮点实现相比，该实现的血流值相对差异的均方根偏差低于0.1%。该系统可以包含一个或多个处理单元，以获得所需的帧率和精度。该系统的性能显著高于迄今报道的其他方法。此外，还设计了一块专用的现场可编程门阵列（FPGA）板来测试所提出的处理系统。该板与一个激光线扫描系统相连，该系统使用64×1光电探测器阵列。各种操作参数的测试结果表明，新系统在噪声和成像速度方面的性能比以前的系统更好。
