圆盘单极超宽带天线特性研究

随着超宽带通信和软件无线电技术的深入研究,宽频带与小型化成为当前天线研究领域的热点.圆盘单极天线是一种小型化、馈电简单的超宽带天线.对其进行了详细分析,给出了这种天线的设计方法,讨论了天线尺寸对于其阻抗特性和辐射性能的影响;通过基于时域有限积分法的软件包进行了仿真计算,得出了该天线具有大约30个倍频程的阻抗带宽和方向图带宽,群延时接近常数,并测量了它的阻抗特性.研究结果表明:圆盘单极天线不仅在频域具有超宽带特性,而且具有稳定的相位中心,适合作为时域通信系统天线.

Study of properties of the circular monopole ultrawide-band antenna

With the development of ultrawide-band communication and Software Radio,wide band and miniaturization have become the hottest issues in the current researches on antennas.The circular monopole antenna is a kind of miniaturized ultrawide-band antennas with simple feeding network.Detailed analyses are conducted to determinate the antenna's properties.The design method of the antenna is presented,and the influences on its impedance and radiation properties by varying the dimension parameters of the antenna are discussed.Through simulations based on the FITD software,it is demonstrated that the antenna has an approximately 30 times octave impedance bandwidth,good consistency of the horizon directivity diagram and the constant group delay.The impedence characteristics of the antenna are also got.The research results show that the circular monopole antenna not only has the ultrawide band in frequency domain,but also the stable phase center,which make the antenna suitable for the antennas in the time domain communication systems.