An Improvement in Three-Dimensional Pure Proportional Navigation Guidance

This article proposes an improved version of 3-D pure proportional navigation (PPN) against a manoeuvring target. The main research hypothesis is that the performance of 3-D PPN can be improved by properly selecting the direction of the guidance command as there exists an infinite number of potential directions complying with the PPN concept in 3-D space. Analysis on the relative motion confirms the validity of the hypothesis and leads to the development of a new guidance algorithm. Unlike traditional 3-D PPN, the guidance algorithm developed adapts the direction, but maintains the magnitude of the commanded acceleration proportional to only the line-of-sight rate. The validity and performance of the proposed guidance algorithm are investigated through theoretical analysis and numerical simulations.