Design And Development Of UWB Antenna Based On Fractal Structure

The rapid development of communication system requires more and more on the communication equipment. Today, the communications equipment is moving in the direction of the development of integration and broadband, therefore, antenna in communications equipment, must have miniaturization and broadband characteristics. There are many methods proposed to realize the miniaturization and broadband characteristic of the antennas. However, these methods are so specialized that only some aspects of the demand can be met while the overall performance of the antenna is decreased to satisfy the communication system. In this paper, the antenna combined with fractal theory is improved, without affecting the antenna performance of ultra wideband antenna to achieve miniaturization of the target, so, it has potential applications in the study of ultra wideband antennas based on fractal structure.Firstly, this paper introduces the research background and the domestic and developmental status of UWB antenna, and described in detail towards the miniaturization of antenna and broadband in a variety of ways, and then introduces the basic theory of fractal, and analyze several typical iterative generation of fractal antenna pattern.These studies provided for ultra-wideband antenna design based on fractal theory and ideas.Secondly, using fractal technique, two compact fractal antenna has been designed. Fractal structure has two important features: space-filling and self-similarity. Fractal antennas due to space filling the current path on the surface of the antenna can be increased, so that the electrical length of the antenna, and achieve the goals of the miniaturization of antenna. Self-similarity of fractal antenna characteristics can increase the resonant frequency of the antenna, and then to broaden the bandwidth of the antenna. The first antenna is a kind of fractal antenna, which is a combination of cantor and minkowski, the floor of the antennas using fractal structure of minkowski, patch by cantor fractal structure, realized the miniaturization of antenna with broadband. Final antenna is to realize 3.1-12.6GHz bands, meet the requirements of ultra-wideband antenna size is only 14mm?20mm; Second antenna is Sierpinski fractal antenna structure by increasing the fractal iteration count, change the antenna’s surface current flow, lower center frequencies, to achieve the miniaturization of antenna, antenna operating frequency of 2.8-12.17 GHz eventually, the antenna dimensions 14mm?25mm, the antenna is in the case of ultra-high broadband realizes miniaturization of antenna required.Finally, the processing of the antenna, and measure key indicators, measurements and simulation results coincide, basically meet the requirements of ultra-waveband communication system in order to verify based on fractal structure of ultra waveband antennas can effectively reduce antenna size. Design of the antenna has good performance in the article, the advantages of simple structure, small size, ease of integration, has a certain practical value.