Analysis And Simulation Research On The Influence Of Spatial Modulation Full Polarization Imaging Bandwidth

The spatial modulation full polarization imaging system can obtain full polarization component information at the same time,and obtain multiple complementary information from it.The spatial modulation full-polarization imaging system adopts a static modulation structure,which can realize the polarization imaging detection of moving targets,so it belongs to one of the simultaneous polarization imaging methods.This article introduces the research progress of spatial modulation full polarization imaging technology in related fields at home and abroad,and elaborates the development status of spatial modulation full polarization imaging information processing technology in detail.According to the structural characteristics of the spatially modulated full-polarization imaging system,the effect of the effective spectral bandwidth on the accuracy of interferometric data demodulation is studied.At the same time,the system scheme is designed based on the interferogram and the difference reconstruction algorithm,and its effectiveness is verified.The main content of this paper is as follows:1)Introduction of spatial modulation full polarization imaging system.This article first starts with the principle of spatial amplitude modulation and introduces the system structure of the spatially modulated all-polarization imaging system.Then,starting from the design scheme of the spatially modulated all-polarization imaging system,it focuses on the key components of the spatial modulation module in the system.Then according to the characteristics of these components,the modulation principle of the spatially modulated full-polarization imaging system is explained.2)Research on the influence of system components on the interferogram.This article studies the influence of the thickness of the polarizer on the interferogram.The interferogram obtained through experiments is transformed from the spatial domain to the frequency domain through simulation,and the spectrogram is analyzed to explore the reasons for the deviation of the theoretical and actual spectrograms.3)Research on the effect of effective spectral bandwidth on the accuracy of interferogram demodulation.This paper analyzes and researches the modulation model of the spatially modulated full-polarization imaging system.According to the expression of the band width criterion,the image reconstruction algorithm in the effective spectral range is revised,and finally the demodulation accuracy of different bandwidths is simulated and analyzed.The research results show that within the effective spectral range,the corrected image reconstruction algorithm can improve the parametric demodulation accuracy,and the polarization degree demodulation error is less than 6.5%,which is better than the reconstruction effect before correction.And within a certain range beyond the effective spectral bandwidth,the demodulation effect of the corrected image reconstruction algorithm is ideal,which broadens the effective spectral range and ensures the maximum luminous flux as much as possible.The research results provide a new idea for the bandwidth design of the spatially modulated all-polarization imaging system.4)Simulation verification of interferogram and difference reconstruction algorithm.This article proposes a method to restore the all-resolution intensity image with two inverted snapshots to eliminate the polarization component of the crosstalk.The simulation results show that the SSIM of the demodulated image obtained by the interferogram and difference reconstruction algorithm is higher than the SSIM of the demodulated image obtained by the traditional image reconstruction algorithm,which verifies the feasibility of the algorithm.