<title>Investigation of the optical sampling between the infrared resistor array projector and the unit under test for hardware-in-the-loop testing</title>

Abstract

Kinetic Energy Weapon (KEW) programs under the Ballistic Missile Defense Office (BMDO) need high fidelity, fast framing infrared (IR) imaging seekers. As imaging sensors have matured to support BMDO, the complexity of functions assigned to KEW weapon systems has amplified the necessity for robust hardware-in-the-loop (HWIL) simulation facilities to reduce program risk. The IR projector, an integral component of a HWIL simulation, must reproduce the real world with enough fidelity that the unit under test's software will respond to the projected scenario of images as though it were viewing the real world. The MOSFET resistor array IR scene projector shows great promise for both cryogenic vacuum chamber and room temperature testing. The resistor array breaks up the analog world into discrete pieces, much like a focal plane array (FPA). Extensive debate has taken place since the inception of the resistor array as to how many resistors need to be projected into one FPA detector. Can one resistor be matched to one FPA detector, or does the Nyquist rate of at least 2:1 sampling take precedence? Testing was accomplished at the Wright Laboratory Kinetic Kill Vehicle Hardware-in-the-Loop Simulator that utilized a 5:1 zoom collimator and the Wideband Infrared Scene Projector resistor array to project in the 1:1, 1.3:1, 2:1, and 3:1 cases. This paper discusses the results of those tests.