Abstract: Based on error analysis of the C-W guidance, the article shows that the main perturbation sources of C-W impulse guidance are linearization error, relative J2 term perturbation, and impulse assumption error of thrusters . When obtaining the analytic solution of perturbed relative motion equation, an aiming point modification technique is induced to improve guidance accuracy at limited increase of computational effort, and the actual rendezvous trajectory and the fuel consumption are close to optimal ones.

Key words: C-W guidance, J2 term perturbation, aiming point