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《中国航空学报》2022,35(8):7-11
An active, compact, wideband, receiving filtenna with power adaptation for space-limited wireless platforms is presented. By organically combining a filtering antenna and a Variable Gain Amplifier (VGA), the proposed co-designed active filtenna is achieved. Its power adaptation is empowered by controlling gain of the VGA unit. A demonstrated prototype with a compact overall size is fabricated, assembled and measured. Good performances are achieved. Furthermore, in any condition, the proposed active filtenna displays outstanding impedance matching (|S11| < ?10 dB) and high passband skirt selectivity at upper and lower stopbands (Selectivity ≥ 170 dB/GHz). 相似文献
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《中国航空学报》2023,36(2):29-40
Due to the pneumatic heating and combustion effect, the scramjet engine of hypersonic vehicle faces high temperature challenge. It is necessary to comprehensively consider its thermal management and power generation together. A new Power and Thermal Management System (PTMS) combined with Supercritical Carbon Dioxide (SCO2) closed Brayton cycle and fuel vapor turbine is proposed and discussed in this paper. The new PTMS can meet the cooling requirement of hypersonic vehicle at Mach number 6–7, and avoid the coking and scrapping in the scramjet cooling channels. Compared with the PTMS only based on fuel vapor turbine, the new PTMS utilizes the waste heat of scramjet to generate more electricity. In addition, it can reduce the use of fuel sink for cooling, and the additional weight penalty can be compensated for long endurance hypersonic flight. 相似文献