一种Ka频段宽带多波束相控阵的设计

Design of a Ka-band Wideband Multibeam Phased Array

【目的】全球已步入第5代移动通信技术(5G)和卫星互联网时代,各领域对通信速率和容量的需求激增,传统抛物面和窄带平面相控阵天线系统的应用受到带宽和波束形成数量等因素的限制。文章基于相关产业领域的现状、趋势和宽带多目标的应用需求,对Ka频段宽带多波束固态相控阵技术展开了研究。【方法】文章从理论上建立并推导了相控阵天线方向图的通用矢量数学仿真模型,研究了相控阵天线的子阵划分、孔径效应和渡越时间等问题,设计了基于阵元级电移相与子阵级光延时相结合的宽带多波束相控阵系统。前端单个集成子阵采用不同材料基板的三维高密度异构瓦式集成方案,极大地提高了子阵集成度;子阵后级采用基于光开关、高精度光纤延迟线和波分复用等技术相结合的光真时延(OTTD)方法,实现了子阵级的多通道延时和多波束合成。【结果】通过对Ka频段宽带多波束接收相控阵系统原理样机进行集成与测试,验证了原理样机克服了孔径渡越时间和波束偏斜等带宽限制问题。原理样机可实现对Ka频段8个独立接收波束的宽角度扫描,每个接收波束的最高数据传输率可达1500 Mbit/s。【结论】测试结果证明,文章所提系统具有集成度高、带宽大和可形成多个独立波束等优势。研究成果将有助于促进宽带多波束固态相控阵的进一步发展,为Ka频段宽带多目标相控阵的后续工程化和产品化奠定了理论和实践基础。

【Objective】The world has entered the era of 5th Generation Mobile Communication Technology(5G)and satellite Internet,and the demand for communication speed and capacity in various fields has surged,while the application of traditional parabolic and narrowband planar phased array antenna systems is limited by factors such as bandwidth and beamforming.Based on the current trend of related industries and the application requirements of broadband multi-target,this paper studies the Ka-band wideband multi-beam solid-state phased array technology.【Methods】This paper theoretically establishes and derives a general vector mathematical simulation model of phased array antenna pattern,studies the subarray division,aperture effect,and crossing time of phased array antenna,and designs a broadband multibeam phased array system based on the combination of element-level electro-shift phase shift and sub-array stage optical-delay.The front-end single integrated subarray adopts the three-dimensional high-density heterogeneous tile integration scheme of different material substrates,which greatly improves the integration degree of the subarray.The sub-array post-stage adopts the Optical True Time Delay(OTTD)method based on optical switching,high-precision optical fiber delay line and wavelength division multiplexing to realize multi-channel delay and multi-beam synthesis of the sub-array stage.【Results】By integrating and testing the principle prototype of the Ka-band wideband multi-beam receiving phased array system,it is verified that the principle prototype overcomes the bandwidth limitation problems such as aperture crossing time and beam skew.The prototype can realize the wide-angle scanning of eight independent receiving beams in the Ka-band,and the maximum transmission data rate of each receiving beam can reach 1500 Mbit/s.【Conclusion】The test results show that the system has the advantages of high integration,large bandwidth,and multiple independent beams.The research results will help promote the further development of wideband multi-beam solid-state phased array,and lay a theoretical and practical foundation for the subsequent engineering and productization of Ka-band wideband multi-target phased array.