Study on effect of inertial device error in motion compensation subsystem on SAR image resolution

This paper explores the relationship between inertial device error and synthetic aperture radar (SAR) image resolution in order to improve the performance and cost ratio of SAR motion compensation system. The relationship will help the researchers to develop the SAR motion compensation subsystem with corresponding precision. First this paper describes the solution and fixing way of SAR motion compensation subsystem, and then figures out the different influence of inertial device error (on different axes) on antenna position measurement precision. Finally the relation between SAR image resolution and inertial device error is established by taking advantage of the relation between SAR image resolution and antenna position measurement error. From the analysis and emulation it can be seen that the accelerometer on x-axis and the gyro on y-axis are much more important than other inertial devices for SAR image resolution. However, even though inertial devices with same accuracy are used different SAR wave lengths and coherent times will cause different image resolutions. Emulations of SAR image of single point target verify the above conclusions.