弹光调制非等相位干涉信号的快速光谱反演算法

Research for Fast Spectrum Recovery Algorithm of PEM Nonequiphase Phase Interference Signal

在弹光调制傅里叶变换光谱仪(PEM-FTS)中,由于调制光程差的非线性,不能直接采用快速傅里叶变换(FFT)进行反演光谱,且直接计算开销过大。首先在Matlab软件中用非均匀快速傅里叶变换算法(NUFFT)对PEM非等相位干涉信号进行了软件仿真,其次设计了以TMS320C6713高性能浮点数字信号处理器(DSP)芯片为核心的光谱信息处理系统,实现了硬件上的光谱实时处理。研究表明,算法对光谱反演具有速度快、精度高等优点,1024点光谱反演的速度较直接运算的速度提高20多倍,反演精度可达0.78%。

In the photoelastic modulator-Fourier transform optical path difference is nonlinear, the fast Fourier transform spectrometer （PEM-FTS）, because the modulation （FFT） cannot be directly used for spectrum recovery, and direct computing cost is too much. The phase of PEM interference signal is simulated by Matlab with the non- uniform fast Fourier transform algorithm （NUFFT）, and then the core of the spectrum information processing system is designed with TMS320C6713 floating-point digital signal processer （DSP）, finally, it realized the real-time processing of the spectrum on hardware. The result shows that the algorithm for spectrum recovery has some advantages, such as fast running speed, high accuracy and so on. 1024 point spectrum recovery speed is 20 times more than direct operation speed, recovery precision can reach 0.78 %.