Synthetic Aperture Positioning: A Review

Obtaining precise position of interested emitters passively has wide applications in both civilian and military fields. Different from traditional parameter measurement and direct position determination (DPD) method, recently a new passive localization method based on synthetic aperture technique, named synthetic aperture positioning (SAP), has been proposed. The method compensates for the nonlinear phase produced by relative motion between the moving platform and the emitter, achieving coherent summation of intercepted signals. The SAP can obtain high-resolution and high-precision localization results at a low signal-to-noise ratio. This paper summarizes the research progress of SAP, including localization principles, spaceborne applications, and application scope analysis. Besides, the possible future outlook of SAP is considered.