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The Prognostics and Health Management (PHM) system for radar equipment is paid more and more attention by researchers in recent years. Owing to its high reliability and performance, the Active Phased Array Radar (APAR) has been playing an increasingly important role in the modern radar field which is composed of thousands of solid-state Transmit/Receive (T/R) modules. As the power source of the T/R module, gallium arsenide metal-semiconductor field effect transistor (GaAs MESFET) has been widely used due to its higher electron mobility, operating frequency, power-added efficiency and lower noise figures than silicon MOSFET. However, the performance of GaAs MESFET is influenced by its operating temperature significantly. In order to achieve effective fault injection for the PHM system, it's necessary to get temperature effects on GaAs MESFET. A simplified GaAs MESFET equivalent circuit model based on specific physical properties is proposed and realized on the EDA software. It can help the optimizing of device's structure and materials' parameters. What is more, it realizes the performance simulation under varied temperatures, thus the degradation of GaAs MESFET's output parameters can be predicted by monitoring its temperature.

To save the weight and volume of the bracket, the avionic devices are sometimes fixed onto the airframe from outside directly in the design of air craft with small dimension, which will always lead to an abnormal geometry of the avionic device's case and rearranging of the circuit board assemblies (CBAs), to achieve the aerodynamics goal. However, the inner environment and the air flow outside the craft, which can affect the temperature distribution over the CBAs prominently, have to be considered during thermal analysis at the same time. This paper recommends and presents a method of avionic device thermal simulation and analysis, which can solve the problems caused by the abnormal geometry of the case and the air flow condition. Thermal model should be amended and verified by physical test, and the thermal design of the device can be improved on the basis of thermal simulation. Appropriate baffle and fixed flow also should be added to simulate the real air flow condition in the case.

Aiming at the problem that traditional regression analysis can not reflect the randomness of performance degradation, which happened in the process of statistical analysis of component accelerated storage degradation test, the performance degradation process of the continuous cumulative damage degradation failure component is described by the stochastic process method. The component storage reliability models with the dependent and independent multi-performance parameters were established according to the analysis of the correlation among multi-performance parameters degradation, and the component storage reliability evaluation based on multi-performance parameters degradation was achieved. The method has been applied to the multi-performance parameters degradation analysis of a certain type of the tantalum capacitor and obtained the average storage life expectancy and the storage reliability of this type of the tantalum capacitor, which has certain practical value in engineering.

To improve the productivity and mission availability of discrete processing system, a mission reliability model is presented and the modeling method is introduced. During the modeling, producing unqualified products is defined as the failure of processing system. Both equipment failures and processing failures including handlers, methods, materials, etc, which will result in unqualified products, are considered synchronously. The connections between each failure unit are also built. The reliability indexes are proposed based on the mission reliability model and the calculation method are researched. Finally, the mission reliability model of an actual manufacturing process of a certain product is built, and the relevant indexes are calculated and evaluated.