一款360°连续扫描圆形阵列天线设计

Design of a 360°continuously scanning circular array anttena

针对室内通信系统,设计了一款具有360°方位角连续扫描特性的圆形阵列天线.圆形阵列天线由8个端射单极子八木天线阵元按旋转对称方式构成,每个天线阵元包含一个激励单极子、一个反射器和4个引向器.采用同幅同相激励时,阵列天线可以工作于全向辐射模式;采用扩展最大功率传输效率法计算最佳激励分布时,阵列天线工作于定向辐射模式.仿真和实验结果表明,阵列天线工作于全向辐射模式的平均增益为3.78 dBi,增益波动小于2.0 dBi;阵列天线工作于定向辐射模式时的波束指向可以实现360°方位角连续扫描,并保证了定向波束增益最大化和水平方位指向,定向波束最大增益达到11.1 dBi,方位角扫描增益波动小于0.4 dBi,前后比大于12.5 dB.设计的圆形阵列天线具有定向波束增益高、在方位角可连续扫描等技术优势,可用于未来室内小基站系统.

In this paper,a 360°continuously scanning circular array antenna is presented.The circular array consists of eight Yagi-Uda monopoles,each one consisting of a driver,a reflector and four directors.When the circular array is fed identically,an azimuthal omnidirectional pattern is obtained.When the circular array is fed with an optimized distribution of excitations that is calculated by the expanded method of maximum power transmission efficiency,an azimuthal directional pattern with maximum directional gain is obtained.The measurement and simulation results indicate that the average gain of the omnidirectional pattern is about3.78 dBi with azimuthal fluctuation of less than 2.0 dBi,and the maximum gain of the directional pattern is about 11.1 dBi with azimuthal continuously scanning fluctuation of less than 0.4 dBi and front-to-back ratio of larger than 12.5 dB.The reported circular array antenna is featured by high directional gain and 360°azimuthal beam continuous scanning,and it has potential applications in indoor communications.