基于空谱差异的多天线抗干扰理论与技术研究

Due to the openness of wireless channels, the communication is easy to be jammed by the outside environment. It can be said that the development of wireless communications is just a history of anti-jamming. The essence of anti-jamming is to discover the difference between signal and jamming to realize their separation. This project utilizes the abundant spatial resources provided by multiple antennas, focuses on their most important distinction- - spatial spectrum difference, and enhances their separability based on the divergence between their physical paths in space. The project mainly concentrates on 3 sections: (1) The abstraction of spatial channel characteristic difference. (2) The theoretical far/near-field model based on spatial spectrum difference. (3) The optimal transmit/receive filter design for spatial anti-jamming. In addition, a multiple-antenna test-bed will be set up, and the corresponding test scheme of anti-jamming performance will be designed. The project anticipates to obtain theoretical break-through and technical innovation in the above areas, which will actively promote the development of wireless anti-jamming study.

由于无线信道的开放性，通信过程很容易受到外界的干扰。可以说，无线通信的发展史就是一部与干扰抗争的历史。抗干扰的实质是寻找信号与干扰的特征差异并实现分离。本项目利用多天线系统提供的丰富空域资源，着眼于信号与干扰最大的不同点- - 空谱差异，借助两者历经空间物理信道的不同，增强了信号与干扰的可分性。项目重点从三个方面展开研究：1）空域信道特征差异的提取；2）基于空谱差异的远、近场抗干扰理论模型；3）空域抗干扰最佳收发滤波器的设计。另外，还将架设多天线实验床，设计相应的抗干扰性能验证方案。本项目预期在上述几个方面获得理论突破和技术创新，对促进无线通信抗干扰的研究起到积极推动作用。

由于无线信道的开放性，无线通信很容易受到各式各样的干扰。传统的无线抗干扰手段大多在时域、频域或角度域实现，并未充分挖掘多天线系统的抗干扰潜力。本项目利用多天线系统提供的丰富空域资源，借助信号与干扰历经的空间物理信道不同，研究了基于空谱差异的多天线抗干扰机制与方案。具体研究内容包括：1）通过对近远场空域信道特征的分析，分别建立了近远场空域抗干扰的模型和机制，为后续抗干扰方案的设计提供理论指导；2）利用近场条件下信号与干扰存在的子空间差异，设计了基于子空间投影的收发联合抗干扰方案，并进一步与时域、频域资源结合衍生出基于空时跳变和空频跳变的收发联合抗干扰方案；3）针对远场条件下出现的维度坍塌问题，通过引入跳空抗干扰机制使其维度张开，设计了基于P次跳空的空域抗干扰方案，并进一步研究了基于跳空的多源抗干扰DOA估计方案和多用户MIMO系统抗干扰方案。4）搭建了多天线抗干扰实验床，对近远场条件下的抗干扰理论和方案进行了仿真和实验验证。总的来说，本项目上述方面的研究为无线抗干扰提供了一类新思路、新方法，对该领域的发展起到了积极的推动作用。