Analysis Of Random Vibration On Image Quality Degradation Of TDICCD Camera

Because of the advantages of high Signal to Noise Ratio (SNR) and highsensitivity, TDICCD are widely used in the field of remote sensing, also because ofthe operating characteristics of the TDI detector, the vibration image motionaffected the image quality of remote sensor sensitively. As a result of the impact ofrandom vibration image motion is very complex, there is little research in this area.This paper focuses on the method that calculate Modulation Transfer Function(MTF)of random vibration image motion, analysis random vibration impact on imagequality of TDICCD camera, to improve the remote sensing imaging system’s imagequality and perfect the link simulation to provide important support.First, we analyzed the reasons of remote camera generate flutter and the imagemotion type. As the satellite special working environment, subjected to variousincentives are random uneven, resulting in image motion sensing systems are mostlyrandom. Commonly use MTF to measure to the system imaging capabilities.Analyzed random vibration image motion we found, traditional method of calculateMTF can not be used to calculate the random vibration image motion MTF; and italso has limitations to calculate low-frequency harmonic vibration, so we need toexplore the method of calculate random vibration image motion MTF.According to the characteristics of random vibration and the form that it causesimage point blur, we analyzed three methods of calculate MTF: estimation method,statistical moment method and decomposition method. The error range of thesemethods has been proved are allowable, they can analysis the influence of randomvibration image motion on MTF comprehensively. The Power Spectral Density(PSD) is also important information of vibration, this paper based on PSD,Bandwidth (B) and frequency to analyze the vibration. In based on above discuss,we analyzed random vibration on image quality degradation of TDICCD camerawith the increase of TDI integration number, and combined SNR parametersdiscussed TDI series reasonable selection criteria.Finally, the remote sensing images digital simulations were carried out basedon the principle of TDICCD dynamic imaging. We have established a simulationmodel of random vibration effects on image resolution, and use bilinearinterpolation sampling of the target scene to Kurtosis and No-reference StructureSharpness (NRSS) as the standard evaluation image clarity. Along TDI direction andperpendicular TDI direction simulation random vibration effects on image quality,and think about the influence of TDI series. Simulation results show that along TDI direction main cause image blur, and the blur increases with the increase ofintegration stages, perpendicular TDI direction cause image blur and geometricdistortion, and the geometric distortion are not transform with the increase of TDIseries, the theoretical analysis consistent with digital simulation results.