星载DBF多波束发射有源阵列天线

DBF Multi-Beam Transmitting Phased Array Antenna on LEO Satellite

低轨通信卫星大容量、终端小型化要求卫星采用多波束天线技术来实现高增益、宽覆盖.本文针对低轨CDMA通信系统,设计了具有近"等通量"覆盖的平面阵列多波束发射天线,该天线由61微带单元天线阵、61个发射射频通道和数字波束形成网络组成;数字波束成形网络对输入的16个波束信号进行正交化、加权处理输出61路中频信号,由发射射频通道完成上变频和信号放大,最后通过天线阵辐射出去在空间形成期望的16个赋形波束覆盖.文章详细介绍了天线的实现方法和试验结果,通过对16波束发射天线原理样机的测试,结果表明天线各指标都符合设计要求,有效验证了天线系统设计的正确性.

To meet the requirements of large system capacity and miniaturized terminal of mobile satellite communication,Muti-beam array antenna is adopted to realize the high gain and wide coverage by LEO satellite.This paper presents a planar transmitter array antenna with equal flux density coverage according to CDMA standard utilized by LEO satellite.The phased array antenna consists of an array antenna with 61 micro-strip elements,61 RF front ends,and digital beam forming network（BFN）.Orthogonal transform and phase-amplitude adjustment are completed in digital BFN.The 61-channel IF signals outputted by digital BFN are up-converted and amplified by RF front ends,finally transmitted by array antenna to realize the desired shaped-beam coverage.The design methodology and measured results of DBF phased array antenna is discussed in the paper.The measurements demonstrate that all the parameters of array antenna are consistent with the predefined requirements,which validates the rationality of system design and project implementation.