Multi-Broadband Antenna And Its Miniaturization

Due to the potential applications of frequency-hopping and spread-spectrum techniques in the modern military secure communication systems, the development of broadband omnidirectional miniature antennas, which are known as key components of the communication systems, is an urgent and important issue in theory and applications. Firstly, self-structuring antennas (SSAs) are investigated in this paper. An SSA has the ability to alter its electrical shape in response to changes in its environment or in response to the requirement of the users, so it can work in the optimal status. This propeity makes an SSA suitable for using in a numerous situations. The basic principles and potential applications of the SSA are described. The loop SSA antenna is studied by the moment method (MOM) with the emphasis on its multi-band properties produced by the states of the electrical switch. Finally, a novel wideband patch dipole antenna is simulated and analyzed by the electromagnetic software Ansoft HFSS. The calculated results agree well with the experimental results. The relative bandwidth of this antenna can reach 66.7 percent with the VSWR less than 2, which shows the good electric characteristics of this kind of antenna.