【摘 要】
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In this paper,a mast antenna for communications consists of satellite navigation and UHF/VHF antenna is proposed.On the top of the mast system includes a sa
【机 构】
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Xi'an Research Institute of Navigation Technology,Xi'an,China,710068
论文部分内容阅读
In this paper,a mast antenna for communications consists of satellite navigation and UHF/VHF antenna is proposed.On the top of the mast system includes a satellite navigation antennawhich is fed by the L-probe with its phase difference of 90°.Under the antenna a broadband omni-directional antenna utilize dual-parasitic structures with a metal pole through the radiator for UHF/VHF operation is designed.The radiator includes biconical-structure and thick dipole in order to reducing the size,by use of this structure to improve the impedance.The working frequency of the satellite navigation antenna can cover BD,GPS,Glonass satellite navigation system.The working frequency band of the VHF/UHF antenna is 120-550MHz.In the whole band the VSWR is less than 2.5.The measured and simulated results show that theantenna has good radiation pattern properties over high and low frequency.All the efficient results show that the UHF/VHF antenna can combine satellite navigation antenna well to form a new mast antenna system that has important utility values in multi-functional satellite navigationcommunication.
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