A Research on an Algorithm for Removing Bowtie Effect

A kind of overlapping effect called bowtie effect occurs around the edge of the scanning swath for optical-mechanical scanner as long as sensors which have swaths wider than one pixel, which aggravates its degree exponentially toward the swath edge. In order to remove bowtie effect, three main factors (satellite motion, earth rotation, scanner mirror) that affect the scanning image are analyzed firstly. Then, a geometry mathematical model is established based on the theory of scanning imaging. An analytical algorithm, which requires no ephemeris information, is proposed based on the mathematical model to remove bowtie effect. This algorithm works by firstly making geometric correction for each swath. Then, at the same time of splicing all the corrected swaths, the bowtie effect was removed. Finally, the validity of our algorithm is verified by removing MODIS bowtie effect.