近距离散射测量用Ka波段紧凑型阵列天线

Compact array antenna in Ka band for near-field scattering measurements

设计了一种工作于Ka波段的、用于近距离散射测量的四单元紧凑型阵列天线,在阵列近场实现了较均匀的幅相分布.辐射单元由角锥喇叭天线和E面金属板透镜天线组成.馈电网络由魔T、弯波导组成,为各辐射单元提供等幅同相馈电.采用阵列形式和采用透镜调节喇叭口面相位,都较大程度地减小了阵列的纵向尺寸,且电性能也有明显改善.给出了阵列天线近场的测试结果,并对测试结果进行了分析.在距离阵列口面0.5 m处,在与阵列宽度相同的范围内,幅度和相位波动分别在±2.5 dB和±25°左右.

A four-element compact array antenna was designed operating in Ka band for near-field scattering measurements,and an approximately uniform amplitude and phase distribution in the near fields of array antenna was achieved.The radiating element consists of pyramidal horn antenna and E-plane metal-lens antenna.The feed network consists of magic T and bend waveguides,providing equal magnitude and phase signals for radiating elements.The lengthways length of the array is significantly reduced by employing array and E-plane metal-lens antenna,and the electrical performance is also improved.The near fields of array antenna was tested,and the test results were analyzed.In the plane 0.5 m from the aperture of the array with width equal to that of the array,the amplitude and phase ripples are around ±2.5 dB and ±25° respectively.