Analysis And Optimal Design On Thermal Characteristics Of An RF Coaxial Switch

RF coaxial switche has been widely used in automated test equipment and mobile communication systems (signal base, high-frequency amplifiers), with low insertion loss, low VSWR, high power broadband transmission capacity and good performance characteristics. It has been one of the most important part of the electromechanical components in communication systems engineering, but the market has been monopolized by foreign products so long. Recently, to enhance the increace of the frequency and power capacity of the transmitted signal, system performance degradation and system failure cases caused by the RF coaxial switch heating problem have occurred. Therefore, detailed theoretical calculation and simulation analysis of the thermal characteristics of the RF coaxial switch make difference to our R&D capabilities of the RF coaxial switch.In this paper, the heating mechanism and theoretical calculations of the electromagnetic systems and RF switching systems have been proposed, seeking the appropriate signal frequency, power distribution of the various components of power loss, compared identify major sources of heat. Based on this analysis relate to the theory of heat transfer and heat process to resolve the ANSYS Workbench platform for co-simulation analysis of the mechanism.In this paper, the RF coaxial power switch has been modeled by UG,, and then turn on the Workbench environment of electromagnetic systems and RF switching system for steady-state thermal analysis, in which the RF switching system heating issues related to electricity-magneto-thermal multi-field coupling problem, apply the Workbench can be convenient and efficient to complete the process of simulation analysis, by analyzing the overall heat transfer path, the completion of the whole thermal boundary conditions imposed while loading electromagnetic systems and RF switching system heat source, to get the machine’s steady-state temperature distribution, and through the T-type thermocouple simulation results were verified by experiments.In this paper, Based on the obtained RF coaxial switch the machine on the basis of steady-state temperature distribution, and then analyzes the effect of temperature changes in material properties related parts and components due to exposure to see different linear expansion coefficient due to thermal deformation of its RF performance. The latter analysis process designed to power-magneto-thermal-structural multi-field coupling problem in the Workbench environment through a cascade of modules to complete the entire process cycle simulation. The results obtained by the analysis, RF coaxial switch thermal characteristics resulting from changes in material properties and components in the form of variables on the RF performance, its performance degradation mechanism of the foundation.In this paper, the influencing factors of RF coaxial switches steady temperature have been analysed from three aspects whitch include the electrical parameters, material properties and thermal parameters. The key working factor of RF coaxial switch’s steady-state temperature have been proved. On this basis, orthogonal experiment has been used in optimizing the critical dimensions of RF coaxial switching system components to improve its RF performance while reducing the steady-state temperature. All of the work make difference to RF coaxial switch R&D capabilities and also the production.