Mathematical modeling and digital system design for space-based camera imaging and detection links

To address the digital construction requirements of space-based optical systems, this paper takes the construction of fulllink mathematical models for imaging and detection of space-based cameras and the design of digital systems as its research object, and proposes a method for building a digital imaging and detection system for digital cameras. The effective working time window of the camera is calculated based on a multi-constraint visibility model; by combining the Bidirectional Reflectance Distribution Function (BRDF) with the global photon mapping algorithm, an end-to-end radiative transfer model of "target radiation-optical system-detector response" is constructed to accurately calculate the target radiance and apparent magnitude at the detector end, thus achieving high-precision simulation of imaging and detection results in high-speed space motion environments. A digital simulation platform based on a three-layer architecture of “data-driven, model solving, and visualization output” is designed, which integrates multi-source data interfaces such as orbit parameters, material properties, and detector parameters, and finally realizes grayscale image output of panchromatic cameras. The constructed mathematical models and digital systems of space-based cameras aim to provide high-fidelity simulated data sources for the verification of space-based image processing algorithms, and offer theoretical basis and technical support for the parameter design of physical cameras, detector selection, and the construction of core modules of space-based imaging digital twin systems.