基于改进型巴特勒矩阵的短波8元圆环阵列多波束技术研究

传统短波接收天线为单一的波束指向天线或全向天线。为提高接收天线增益,同时产生多个波束指向不同方向,提出利用巴特勒矩阵作为短波接收天线阵的无源波束形成网络。在传统8×8巴特勒矩阵结构的基础上,设计改进型8×8巴特勒矩阵。以均匀8元圆环阵列为天线模型,利用FEKO仿真分析了其天线特性。在3~11 MHz频段内,P2、P3、P6、P7四个端口分别在202.5°、292.5°、112.5°、22.5°方向上得到了方向性较强的单一波束,7 MHz时波束增益达到最大11.9 dBi,波瓣3 dB宽度平均为60°;在P1、P4、P5、P8端口产生相同的2个波瓣,7 MHz时其波束增益达到最大9.8 dBi,波瓣3 dB宽度平均为89°。由以上仿真分析得出,该改进型8×8巴特勒矩阵能够同时产生6个波束,波束覆盖8个方向,提高了波束的方向性,提高了天线增益。

HF 8-element Ring Array Multi-beam Technology based on Modified Butler Matrix

The traditional shortwave receiving antenna is usually a single beam pointing antenna or an omnidirectional antenna.In order to improve the gain of the receiving antenna and generate multiple beams pointing in different directions at the same time,a passive beamforming network with Butler matrix as the shortwave receiving antenna array is proposed.Based on the traditional 8×8 Butler matrix structure,a modified 8×8 Butler matrix is designed.With a uniform 8-element ring array as the antenna model,the antenna characteristics are analyzed through FEKO simulation.In the band range of 3~11MHz,a single beam with strong directivity is obtained in the direction of 202.5°,292.5°,112.5°and 22.5°at the four ports of P2,P3,P6 and P7,respectively.At 7MHz,the beam gain reaches the maximum of 11.9dBi and the average width of the lobe of 3dB is 60°.At ports P1,P4,P5 and P8,the same two lobes are generated.At 7MHz,the beam gain reaches the maximum of 9.8dBi,and the average width of 3dB lobe is 89°.Simulation analysis indicates that the modified 8×8 Butler matrix can simultaneously generate 6 beams,and the beams cover 8 directions,which improves the beams directivity and the antenna gain.