Research On Conformal Ultra Wideband Antenna

UWB(Ultra-WideBand) antenna has sharp advantages in large capacity communi-cation, data transmission, electronic reconnaissance and other aspects, monopulse UWB antenna is able to capture signal in quite wide frequency range, general monopulse device uses multiple antennas to obtain pitching angle and azimuth angle of target signal, so as to track the signal. In order to improve the accuracy, the monopulse UWB antenna device and milimeter wave device are combined. the key question is how to keep good sense finding function and non-interfering.Firstly this paper describes the different forms of monopulse radar, proposed further designs of UWB antenna method.Then the concentric passive UWB monopulse radar antenna structure is analyzed, with a pair of microstrip quasi-horn antennas measuring pitching angle, a pair of open end Vivaldi antennas measuring azimuth angle. The principle of these two kinds of antennas are discussed, and a lot of simulation experiments are made to test the influence of parameter, because of the space, the antennas have to be conformed. Common and differential mode signals are obtained, grating lobes appear due to the arrangement of the antennas, feasibility of detecting angle with grating lobes are discussed, the shifting of phase center influences slightly on the angle detecting.Finally a dual-use of four arm Archimedes spiral structure is proposed, the conformal structure has good performance both as a UWB antenna and a millimeter wave paraboloid antenna reflector, simulation results prove that the structure as reflective surface can satisfy the requirement of sense finding though with a bit of degeneration.