Aiming at the problem that the positioning precision of airborne sensor is not easy to be directly evaluated when confronting lateral cross positioning system

shrink ratio experiment of positioning precision is studied. Principle of lateral cross positioning system is introduced and the Cramer-Rao lower bound（ CRLB） of positioning precision is deduced. Scene of shrink ratio experiment is designed and the positioning precision before and after shrink ratio experiment is compared and analyzed. The results provide theoretical support for the shrink ratio experiment of positioning precision. Shrink ratio experiment is verified by simulation. Simulation results show that shrink ratio experiment of lateral cross positioning system is effective and feasible

and can carry out shrink ratio experiment on real scenes beyond 100 km. The shrink ratio Cramer-Rao Lower Bound will reach 100 m magnitude.