This paper analyses the geometry and principle of distributed InSAR(Synthetic Aperture Radar Interferometry) geolocation

and provides a complete closed-form solution to the geolocation problem.Meanwhile

it analyses the sensitivity of the closed-form solution

and proposes the formulations of geolocation precision criterion and system parameters precision criterion.The analysis indicates that the property of geolocation geometry is determined by the angle among sightline vector

baseline vector and master satellite speed vector.The angle made up of sightline-baseline plane and sightline-speed plane is a key parameter

and the bigger the angle

the better the geolocation geometry is.Finally

in Cartwheel formation

a Monte Carlo simulation is performed to prove that the precision analysis is correct.