| Frequency hopping communication which using the broadband transmission antenna is one kind of important technologies in the modern military wireless communications. It can realize the confidentiality of information transmission and implementing effective electronic countermeasure. However the antenna’s impedance and reflection characteristics will be changed as the frequency changes, what is more, the size and shape of the antenna is usually limited due to the size of the aviation equipment and limitations of the aerodynamics requirement, so the impedance matching of the antenna is a difficult problem. This paper designed a small size broadband antenna used in aviation equipment of ultrashort wave frequency hopping communication. In the light of the characteristics of frequency hopping communication, we introduce the passive lossy network and active tunable matching network to complete the matching of the antenna.The author’s main research and achievements are:1. The design of sword form monopole antenna accorded with the demand of air dynamics was completed, the techniques of increassing the antenna’s cross section area and loading arasitic resonant component was used to increase the bandwidth of antenna.2. The design of passive lossy fixed matching network was completed.3. The design of active lossless turnable matching network was completed.4. The comparison of the two matching method was given, it’s significant to the practical application of the antenna.The key prameters of the antenna are:Height:≤400mm.Bandwidth:100MHz～400MHz.VSWR:≤2.5.GAIN:(100MHz-108MHz)≥-10dB,(108MHz-115MHz)≥-8dB,(115MHz～130M Hz)≥-6dB,(130MHz～400MHz)≥-3dB. |
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