基于最大功率传输效率法的近场三维方向图赋形

3-D Near-field Shaping Based on the Method of Maximum Power Transmission Efficiency

讨论如何利用带约束的最大功率传输效率(CMMPTE)法通过阵列天线来综合三维方向图。通过引入测试接收阵列天线,待设计的阵列天线与之构成无线功率传输(WPT)系统,从而将方向图的综合问题转换成WPT系统功率传输效率(PTE)的优化问题。通过调整约束条件,在保证PTE最大化的条件下可获得阵列天线的激励分布,根据激励分布设计馈电网络实现近远场方向图的赋形。作为例子,设计了中心频率为2.45 GHz的赋形天线阵列,该阵列由48个微带天线单元组成,排成六棱柱形状,并在棱柱内部实现了三维圆柱形的电场赋形。

How to synthesize the three-dimensional pattern by using the constrained method of maximum power transmission efficiency(CMMPTE)was discussed in this paper.By introducing test receiving antennas,the antenna array under design and the test receiving array constitute a wireless power transmission(WPT)system,and the synthesis problem is transformed into the optimization power transmission efficiency(PTE)of the WPT system.By adjusting the constraints,the excitation distribution for the array can be determined under condition of ensuring the maximum PTE,and the feeding network is designed according the excitation distribution to realize the shaped pattern in the near or far field region.As an example,a shaped-beam antenna array operating at 2.45 GHz is designed in this paper,the array consists of 48 patch elements arranged in a hexagonal shape,and a 3-D field pattern of cylindrical shape is realized inside the hexagon.