移动台适用的平面型紧凑极化分集天线

给出一种适用于移动台的平面型紧凑极化分集天线。该天线由两个十字交叉的微带分支提供极化分集。每一分支都有单独的微带一垂直探针馈电系统，并在分支上蚀刻有一个细槽以提高两个端口的隔离度。通过电容加载大大缩短了分支长度。利用时域有限差分法，在900MHz频段对该天线进行了分析和优化。天线模型的测量结果与仿真结果基本吻合，在约5％的带宽内两个端口的隔离度大于20dB、回波损耗均低于-10dB。该天线两端口的包络相关系数远小于0．1，能够满足分集的要求。

Compact planar polarization diversity antenna for mobile terminal

This paper presents a compact planar polarization diversity antenna for mobile terminal. The antenna has two crossed microstrip branches, which can provide polarization diversity. Each of the crossed branches has an exclusive microstrip vertical via feed system. To further increase the isolation between the two ports, a slot is etched on each of the crossed branches. The length of each branch is reduced considerably by using capacitive loads. Using the finite difference time domain (FDTD) method, the antenna is analyzed and optimized at the 900MHz frequency band. The antenna model is verified experimentally and a reasonable agreement between the FDTD simulation and measurement results is obtained. A bandwidth of 5% is achieved, over which the return losses for both feed ports are less than -10dB and the isolation between the two ports is larger than 20dB. Envelope correlation of the two ports is much less than 0.1 and meets easily the requirement for achieving diversity.