船载海事卫星通信印刷四臂螺旋天线设计

为了解决四臂螺旋天线馈电结构复杂和网络损耗较大的问题，提出一种集成新型馈电网络结构的印刷四臂螺旋天线。通过大量的计算机电磁仿真分析发现天线的性能主要由螺旋臂的长度、螺旋的直径和螺旋节距的升角决定。基于此，制作了一款应用于船载海事卫星通信的印刷四臂螺旋天线并进行了测试。测试结果表明天线在系统要求的工作频带内驻波比小于1．4，增益高于2dB，半功率波瓣宽度达到140°，上半空间主要区域轴比小于3dB。测试结果与仿真结果具有较好的一致性。天线实际应用效果良好。

Shipboard Printed Quadrifilar Helical Antenna for INMARSAT Satellite Communication

In order to solve the problem such as the complicacy of the feed part and high loss in feeding network about quadrifilar helical antenna, a novel printed quadrifilar helical antenna with integrated feeding network is presented. According to large of computer electromagnetic simulations, the antenna performance is mainly affected by filar length, diameter and pitch angle. A shipboard printed quadrifilar helical antenna for INMARSAT satellite communication was fabricated and measured. The measured results show that the VSWR is less than 1.4 and the gain is better than 2dB in the work band. The half power beam-width is more than 14：0 with axial ratio less than 3dB in the same range. The measured results have a good agreement with the simulated ones. The proposed antenna works properly as a shipboard antenna in practical applications.