A comparative analysis of guidance laws for boost-phase ballistic missile intercept using exo-atmospheric kill vehicles

Abstract

Boost-phase intercept of a threat intercontinental ballistic missile (ICBM) is the first layer of a multilayer missile defense strategy. Space-based interceptors possess certain kinematic advantages over ground-based interceptors in defeating an ICBM threat during boost phase. This paper explores the performance of various guidance laws that might be used by an exo-atmospheric kill vehicle (EKV) launched from a space platform to defeat a hostile, ground-launched ICBM during boost phase. Proportional navigation guidance, bang-bang guidance and predictive guidance are all investigated using simulated missile and EKV trajectories. Performance results are presented with respect to miss distance, intercept time, launch envelope, and total control effort. The total control effort is directly related to fuel consumption, and smaller values translate to less weight in fuel or longer potential intercept ranges. Large launch envelopes mean fewer required EKV carriers. In general, the predictive guidance algorithm outperformed the other guidance algorithms in these simulations, but it did prove to be sensitive to timeto- go errors.