An off-target look angle control guidance law for non-maneuvering moving targets is proposed. Unlike impact angle control guidance laws whose angle requirement is defined on the target, the proposed guidance law controls a look angle on a virtual circle centered on the moving target in the horizontal plane. A closed-form solution is derived using optimal control theory for a nonlinear problem formulation. The resulting guidance law can be expressed as a version of biased proportional navigation. It is shown how the new off-target look angle control can be applied in midcourse guidance problems to handover to terminal homing. The scenarios described include generating a collision course condition at a designated distance from a moving target, circling over a moving target, and attaining a desired look angle on the circle for a fixed target.
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