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Hardware-in-the-loop (HWIL) testing can be used as an efficient and effective means for analyzing the performance of guided missile systems. Due to the limits of current technologies, components of the simulation are limited in their capability to simulate real-world conditions for certain test articles. One component which is critical in an HWIL system for strategic guided missiles is the scene projection or delivery device. To stimulate imaging JR sensors, this scene projector (SP) typically consists of a pixelized in-band source which can be modulated both spatially and temporally to simulate the radiane scene which would be observed during an actual engagement. The SP is driven by a scene generator which provides scene radiance information to the SP under control of a simulation computer, which determines the field-of-view (FOV) composition based on a simulated engagement. In using such a system, a primary concern is that the SP is able to create a scene which produces the proper response in the observing sensor. Another effect which bears examination is the SFs projection method, such as scanning an in-band source to cover the projection FOV. The detailed interaction between the modulated source and the timing of the sensor's detection, integration, and readout processes may cause unrealistic or unexpected sensor behavior. In order to assess the compatibility of a specific sensor viewing a specific SP, a detailed simulation has been developed by Nichols Research Corporation under the direction of the Guided Interceptor Technology Branch (WL/MNSI) of the USAF Wright Laboratory Armament Directorate. This simulation was designed primarily to address issues related to scene projector usage in the Kinetic Kill Vehicle Hardware in the Loop Simulator (KHILS) facility at Eglin AFB, Florida. The simulation allows the user to define: the spatial response of the sensor; the spatial properties of the SP (i.e. the radiance distribution arising from a commanded impulse); the illumination timing of the SP, such as scan format, persistence, etc.; and the integration and readout timing of the sensor. Given sampled values of these response functions, and sampled values of the desired radiance scene, the SP simulation computes the detector outputs in the form of a sensed image. This output image can help to assess the suitability of using the modeled SP for testing the modeled sensor by illustrating potential mismatches. It also provides a means to predict the performance to be expected from this module of the HWIL simulation for a particular test scenario. This paper derives equations which express the sensor output as a function of the input scene, the spatial and temporal response functions of the sensor and the SP, and the spectral response functions of the sensor and SP. Assumptions which affect the implementation and the generality of application are stated and discussed. Results and conclusions are presented for a specific application which illustrate the utility of the simulation
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