Compact Range Implementation of RF Target Glint Signatures for Multi-mode Hardware-in-the-loop Simulations

"This proposal describes a hardware-in-the-loop (HWIL) system for testing millimeter wave radio frequency (RF), multi-mode missile seekers. The system consists of a unique five-axis (three seeker axes plus two target axes) flight motion table (FMT), anoff-axis parabolic RF reflector, RF feeds, and an electronics box for the control of RF phase plane. RF energy of a given target signature is fed into the reflector from a antenna feeds assembly mounted on the inner target axis, at the focal point area ofthe parabolic reflector. The parabolic reflector, together with the three RF antenna feeds (the Compact Range), effectively produces a far-field image of the RF target. Both FMT target axis motion and electronic control of the RF beams (deflection)modify the simulated line-of-sight target angles. Multiple (multiplexing) targets, glint, multi-path, and ECM, can be introduced electronically. To evaluate multi-mode seekers, the center section of the parabolic reflector is replaced with anIR-transparent, but RF-reflective section. An IR scene projector or Semi-Active Laser (SAL) return generator mounts to the FMT target axes, with its image focused on the intersection of the FMT seeker axes. The system eliminates the need for a largeanechoic chamber and "Target Wall" or target motion system used with conventional HWIL systems. The compact range is less expensive to procure and operate than alternative HWIL systems that require an anech