Thermal Control And Shield Design For The Instrumental Module Of The X-Ray Pulsar Navigation Sensor

The X-ray pulsar navigation sensor represents a focal plane detector with a controllable operation environment, meeting the operation requirements of the detector and electronics. The focal plane detector must operate at about -55 degrees C. The heat generated by devices with a high heat consumption of the electronics, may result in performance degradation or even a failure of key devices. The background radiation of the X-ray detector mainly consists of charged particles (electrons, protons, ions, etc.) and dispersed cosmic rays (X-ray, gamma-ray, etc.), which will result in a background noise of the detector, lowering the detector sensitivity, deteriorating performance of the detector and electronics, thus even leading to damages and a failure.The instrumental module, consisting of the detector, the preamplifier, the collimator, the thermo electric coolers (TECs), the housing and the shielding layer, is the critical module of the X-ray pulsar navigation sensor. A good thermal control and shield design must therefore be provided for the instrumental module to improve the sensitivity and ensure normal operation of the detector, as well as to provide shielding from stray light, contamination, and background noise.Firstly, the initial structure of the instrumental module was designed; on this basis thermal design and thermal analysis were implemented. The temperature gradient and temperature distribution in the detector instrument and electronics were obtained. The thermal control measures and materials were selected, which helped to provide a controllable thermal environment for the detector and electronics. Secondly, shield design was developed in order to reduce the effects of space background radiation on the detector. The shielding measures for electrons, protons, ions, and high-energy cosmic X-rays were proposed and appropriate materials and their thicknesses were selected. Finally, the effectiveness of thermal control was verified through computer simulation, providing guide lines for the design of the X-ray pulsar navigation sensor.