基于FPGA+DSP的高速多光谱复现系统研究

Research on high-speed multispectral recurring system based on FPGA+DSP

为了在高速复现多光谱信息的同时,仍能保证对每个光谱复现的精度,提高系统的稳定性,研究了一种基于FPGA+DSP的复现系统。系统利用FPGA对高速AD进行控制,然后将携带不同特征波长信息的干涉条纹传输给DSP进行光谱复现。在DSP中,对不同中心波长的干涉信号采用非均匀插值处理,再通过NUFFT实现分段频域变换处理,进而达到等精度复现每个光谱的效果。实验将Virtex系列FPGA与6745型DSP联用构成处理模块,对660 nm、780 nm和808 nm三个激光同时入射静态干涉模块的干涉条纹进行处理,再完成混合光的光谱复现。结果显示,采用NUFFT分段处理的方式相比单一采样插值法复现的光谱分布效果更好,其三个特征波长信噪比都较高,并且速度比原有方法快近一倍。由此可见,该系统在多光谱数据复现应用中更具优势。

In order to reproduce multi-spectral information at high speed,the accuracy of each spectrum can be guaranteed and the stability of the system can be improved at the same time,a regenerative system based on FPGA+DSP is studied.FPGAs are used to control high-speed AD in the system,and then transmit interference fringes carrying different characteristic wavelength information to the DSP for spectral reproduction.In the DSP,the interference signals of different center wavelengths are processed by non-uniform interpolation,and then the NUMFFT is used to implement the segmentation frequency domain transform process,thereby achieving the effect of reproducing each spectrum with e-qual precision.The Virtex series FPGA is combined with the 6745 DSP to form a processing module.The interference fringes of the 660 nm,780 nm and 808 nm lasers simultaneously entering the static interference module are processed,and the spectral reproduction of the mixed light is completed.The results show that the NUFFT segmentation method is better than the single-sample interpolation method for spectral distribution.Its three characteristic wavelengths have higher signal-to-noise ratios and are nearly twice as fast as the original method.Thus,the system is more advantageous in multi-spectral data reproduction applications.