Geometric Correction Algorithms Research And Error Analysis Of Airborne Whisk Broom Remote Sensing Image

Optical remote sensing imaging technology is an important method of acquiring the earth's information,which has been widely applied in military and civil field.There are many optical remote sensing sensors,and among them linear whisk broom senseor has been widely used in satellite remote sensing.This kind of imaging sensor combines the advantages of whisk broom sensor's wide view field,dynamically adjusting scanning angle and the advantages of push broom' staring imaging feature,higher spatial resolution,higher spectral resolution.This imaging way can increase exposure time without increasing scanning rate,and better imaging quality can also be obtained.But when this kind of sensor applied in airborne remote sensing imaging systems,because of airflow interference,there will be severe distortions in those images caused by the poor posture stability of airborne platform.On the other side,there are different characteristics and requirements between airborne and space-borne linear whisk broom remote sensing system,so corresponding imaging model,correction algorithms and error analysis theory must be built to supply theory base for image application.Based on the above background,this paper carried out related research about airborne whisk broom geometric correction.First imaging model has been introduced,and based on this model,depart the distortion into two part: one is the posture distortion cause by the instability of platform at the imaging moment,and the other is inherent distortion caused by at different sampling time CCD pixels corresponding to different ground pixel size.This paper builts the imaging modle,and based on this decomposition,shows correction algorithms to correct the inherent distortion.Finally,the whole correction procedure is introduced.Simulation experiment and real data experiment have shown the feasibility of those algorithms.Second,there are many parameters and measured data in those algorithms,such as setting angle,scanning parameters,position and posture data,and the measurement accuracy of those datas leads direct influences on correction precision.So,this paper has analyzed the error theories of some key parameters.Experiment results of the effect of different measurement precision to correction precision have been given out.Those results not only can supply some references to the direct position accuracy of this kind of imaging system,but to the key technical indexes of instruments,the measuring precision of key parameters and the posture parameters of platform during reality imaging collecting.