面向分布式上行天线阵列相干合成的多通道幅相光控研究

Coherent synthesis based on distributed uplink antenna array is characterized by high precision, high reliability and scalability etc., which is an important method for the long-distance measurement and control communications. The core of this technology is to control the amplitude and phase of the antenna array, so the radiation fields emitted by multiple antennas are coherently combined, which can achieve the communication capability of an antenna with an ultra-large diameter and ultra-high radiation power. The current single-channel amplitude-phase control and stable transmission methods cannot meet the multi-channel requirements of the antenna array. An all-optical amplitude-phase control topology of distributed antenna coherent synthesis would be built. Firstly, the amplitude-phase error model of spatial coherent synthesis is established, and the relationship between the synthetic efficiency and the amplitude-phase tolerance would be obtained. Secondly, a multi-channel amplitude-phase control method based on integrated waveguide is proposed, and the amplitude-phase relation between photon and microwave would be obtained. Multi-channel passive steady transmission based on multi-wavelength and integrated modulation would be employed. Finally, an equivalent system for spatial coherent synthesis would be constructed by using amplitude and phase scanning, and the proposed amplitude-phase control and steady-state transmission methods would be verified. An amplitude-phase control scheme with high precision, high consistency and simple structure could be supplied for the development of distributed antenna array technology, and would greatly enhance the stability and reliability of long-distance space measurement and control communications.

分布式上行天线阵列相干合成具有精度高、可靠性好、可扩展等优势，是超远距离测控通信的重要发展方向。该技术的核心是对天线阵列进行幅相控制，使多个天线发出的辐射场相干加强，达到超大口径、超高辐射功率天线的测控通信性能。当前的单通道幅相控制和稳相传输不能满足天线阵列的多通道需求。本项目将面向分布式天线相干合成提出全光幅相控制方案。首先，建立空间相干合成的幅相误差模型，揭示合成效率与幅相容差的内在规律。其次，提出基于集成波导的多通道幅相复合光控方法，给出光子与微波的幅相映射关系，发展基于波长分辨和集成调制的多通道被动地面稳相传输方法。最后，构建基于幅相分级扫描的分布式天线相干合成等效实验系统，验证提出的幅相控制和稳相传输方法的有效性。本项目可为分布式天线阵列技术的发展提供控制精度高、通道一致性好、结构简单的幅相光控方法，大力提升远距离空间测控通信的稳定性和可靠性。

分布式上行天线阵列相干合成对天线阵列进行幅相控制，使多个天线发出的辐射场相干加强，具有精度高、可靠性好、可扩展等优势，是超远距离测控通信的重要研究方向。本项目研究了分布式上行天线阵列相干合成远场目标处的辐射场分布，理论推导了相位传输误差、空间传输误差等参量对功率合成效率的影响。开展了多通道集成波导幅相控制和调制研究，基于加载条形波导优化设计了相位-强度调制级联的幅相控制器的结构参数，建立共面波导电极模型，对共面波导电极进行优化设计，获得插入损耗、半波电压等光电特性参数。基于马赫增德尔干涉结构设计了四通道铌酸锂波导电光调制器件，对其单模波导、Y分支、定向耦合器部分的各参数进行了设计与优化，给出了加工容差分析，设计了器件的加工工艺，并完成了器件的制备，搭建测试平台对该器件的光学特性进行测试。提出了微波光子非线性失真补偿方法，借助微波180°电桥和偏振特性双平行马赫-曾德尔调制器(PM-DPMZM)的偏置电压控制，实现了奇次和偶次边带的幅相操控，可灵活实现二阶、三阶非线性失真或两种失真的同时补偿。发展了基于本振倍频和双通道移相的多功能变频方法，该方法将微波光子本振倍频，变频和双通道移相三种功能集成在单一链路中。在稳相方面，实验验证了基于光开关切换的宽带下行传输链路，通过导频信号的往返传输获得由外界环境引起的光纤延迟变化量，控制光纤延迟线补偿该变化量并达到链路的相位稳定。