(yingwen)运动误差对机载双基SAR定位精度的影响1.doc

Influence of the Motion Errors to Airborne BiSAR Geolocation AccuracyYa Li Yong Li College of Electronic and Information Engineering, Nanjing University of Astronautics and Aeronautics No.29 Yudao Street, Nanjing, 210016 China limack@ Abstract—The image based geolocation accuracy is important in evaluating the performance of the bistatic synthetic aperture radar (BiSAR) system. Most of the errors are originated from the insufficient measurement accuracy of the motion parameters. In this paper, given the BiSAR geometric model, the influence on geolocation accuracy caused by the transmitters motion errors from the viewpoints of imaging is mainly analyzed. The Newton iteration method is a method used to solve the nonlinear equations.Mathematic expressions can be derived using the Newton iteration method .Using the derived mathematic expressions in the text, the simulation results are provided to show the quantitative impact of motion errors on the image and target positioning. Keywords-bistatic synthetic aperture radar (BiSAR); geolocation; parameter error I. INTRODUCTION Geolocation accuracy is one of the key terms applied to evaluate performance of synthetic aperture radar (SAR) systems, whose definition is the degree of closeness between the spatial entitys coordinate-dates and the real position of the entity. Those evaluated performance by the location-error is significant to SAR application: in the military reconnaissance, decision-makers have to strictly positioning targets on the ground; in the ocean surveillance, vessel monitoring and sea rescues have to accurate positioning the ships. Bistatic synthetic aperture radar (BiSAR) has separated transmitter and receiver[1].Compared with the monostatic SAR, BiSAR has many advantages such as longer detection range, access to more abundant information, higher mobility and higher elu-sivness, better ECCM capability and anti-intercept capability, hence BiSAR has stronger living ability. These advantages make BiSAR be