基于FPGA和DSP的自适应光学系统在线性能评估的嵌入式处理平台设计

为了实现自适应光学系统性能的在线实时评估,提出并设计了一种基于FPGA和DSP的嵌入式处理平台。该嵌入式处理平台以FPGA作为协处理器,实现前端的高速数据缓存,以DSP作为主处理器,实现后端复杂的信号处理;根据哈特曼波前传感器探测的残余斜率,在线实时计算自适应光学系统的点扩散函数、斯特列尔比、半高全宽和调制传递函数。结果表明,系统点扩散函数计算误差为10-11量级,斯特列尔比的计算误差为10-3量级,半高全宽的计算误差为10-4倍衍射极限,调制传递函数计算误差为10-4量级。该嵌入式处理平台具有运算精度高,结构简单,便于系统集成,通用性强等优点。

The Embedded Processing Platform Design Based on FPGA and DSP of an Adaptive Optics System On-line Performance Evaluation

For on-line real time performance evaluation of an adaptive optics system, an embedded processing platform based on FPGA and DSP is proposed and designed, in which the FPGA is a co-processor for the high-speed data buffer, and the DSP is a main processor for the later complex signal processing. According to the closed-loop data of residual slope detected by Hartmann wavefront sensor, the on-line evaluation of performance parameters of an adaptive optics system is realized on this proposed platform, including point spread function, Strehl ratio, full width half maximum and modulation transfer function. The results indicate that the error levels of point spread function, Strehl ratio, full width half maximum are 10-11, 10-3, 10-4 times as diffraction limit and 10-4, respectively. As well as highly operational precision, this embedded processing platform has a simple structure, which is good for integration, and strong commonality.