一种空气同轴馈电的X波段低副瓣阵列天线

设计了一种应用于雷达系统中的低成本低副瓣阵列天线, 该天线阵包含256个辐射单元, 由四个64单元的子阵组成, 采用波导合成网络进行功率合成.天线单元采用空气同轴馈电的角锥喇叭, 空气同轴馈线内外导体呈方型结构, 其终端为短路馈电方式, 实现了内导体的自支撑设计和较低的传输损耗, 并依据综合幅度分布采用若干数量的不等功分器进行低副瓣设计.测试结果表明, 小于2的驻波带宽为0.5 GHz, 相对带宽为7.5%.另外, 中心频率的增益为30 dB, 增益大于29.5 dB的带宽为0.2 GHz, E面和H面的旁瓣电平为28.5 dB和29 dB.

A low sidelobe planar X-band antenna array with air coaxial feedline

A low sidelobe array antenna is investigated to provide a low-cost and effective solution to radar applications. This antenna array consists of 256 radiating elements divided into four subgroups of 64 elements each, and fed by a rectangular waveguide feed network. The feed structure of the proposed radiation element, which is basically a novel air coaxial-fed pyramidal horn array with shorting termination, can be realized by self-supporting feedline network and with low losses. Low sidelobe design is conducted according to the synthesized amplitude distributions with a number of unequal power dividers. The test results show that measured impedance bandwidth for voltage standing wave ratio(VSWR) less than 2 is within 0.5 GHz, with a relative bandwidth of 7.5%; the measured gain is 30 dB at the center frequency, while it is higher than 29.5 dB at a frequency band of 0.2 GHz; the measured sidelobe level is 28 dB in the E-plane and 29.5 dB in the H-plane.