Two defenders use the proposed guidance law and the augmented

proportional navigation (APN, N = 5, K = 2) with angle restraints in [17], respectively.

Chern, "Solutions of true

proportional navigation for maneuvering and nonmaneuvering targets," Journal of Guidance, Control, and Dynamics, vol.

Sreenatha, 2000, "Fuzzy logic implementation of

proportional navigation guidance," Acta Astronautica, 2000.

The former had an improved guidance subsystem that directed the missile more accurately towards the calculated intercept point, rather than using the "typical"

proportional navigation method.

Banavar, "

Proportional navigation through predictive control," Journal of Guidance, Control, and Dynamics, vol.

Popularly, the

Proportional Navigation law can be decoupled in the "OXY" plane and "OXZ" plane [17]:

The proposed two-phased scheme admits the allowed look angle along with the desired impact angle constraint and switches the

proportional navigation gain at an appropriate instant in the case for engagement.

Proportional navigation guidance law (PNGL) [1-4] has been widely used in the area of homing guidance, which can achieve excellent performance in the presence of a nonmaneuvering target.

These evolved into conical-scan trackers with all-aspect capability and

proportional navigation guidance.

The first term of the right-hand side of the above equation is due to pure

proportional navigation guidance (PPNG) law and the second and third terms pursuit guidance (PG) law.

In any case, a fixed angular error is not enough to defeat a missile using

proportional navigation (Figure 5).