利用旋转轨道角动量的 MIMO-SAR 系统新方案。

A Novel Scheme for MIMO-SAR Systems Using Rotational Orbital Angular Momentum.

机构信息

Science and Technology on Microwave Imaging Laboratory, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China.

School of Electronics, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.

出版信息

Sensors (Basel). 2018 Oct 18;18(10):3511. doi: 10.3390/s18103511.

DOI:10.3390/s18103511

PMID:30340342

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6210029/

Abstract

The vortex electromagnetic (EM) wave with orbital angular momentum (OAM) brings a new degree of freedom for synthetic aperture radar (SAR) imaging, although to date, its application to multi-input multi-output (MIMO) SAR has not yet been widely reported. In this paper, an orbital angular momentum (OAM)-based MIMO-SAR system is proposed. The rotational Doppler Effect (RDE) of vortex EM waves offers a novel scheme for an OAM-based MIMO-SAR system. By transmitting the rotational vortex EM waves, echoes of different OAM modes can be discriminated by a bandpass filter in the range-Doppler domain. The performance of the proposed scheme is independent of the time-variant channel responses, and the wider beam width of the vortex EM waves delivers, for the same antenna aperture size, better performance in terms of swath width and azimuth resolution, in contrast to the plane EM waves. Moreover, the spatial diversity of vortex EM waves shows great potential to enhance the MIMO-SAR system applications, which involve high-resolution wide-swath remote sensing, 3-D imaging, and radar-communication integration. The proposed scheme is verified by proof-of-concept experiments. This work presents a new application of vortex EM waves, which facilitates the development of new-generation and forthcoming SAR systems.

摘要

涡旋电磁波（EM）具有轨道角动量（OAM），为合成孔径雷达（SAR）成像带来了新的自由度，尽管迄今为止，其在多输入多输出（MIMO）SAR 中的应用尚未得到广泛报道。本文提出了一种基于轨道角动量（OAM）的 MIMO-SAR 系统。涡旋 EM 波的旋转多普勒效应（RDE）为基于 OAM 的 MIMO-SAR 系统提供了一种新的方案。通过发射旋转涡旋 EM 波，可以在距离多普勒域中通过带通滤波器来区分不同 OAM 模式的回波。所提出方案的性能与时变信道响应无关，并且与平面 EM 波相比，相同天线孔径尺寸下，涡旋 EM 波更宽的波束宽度提供了更好的测绘带宽度和方位分辨率性能。此外，涡旋 EM 波的空间分集在增强 MIMO-SAR 系统应用方面具有很大的潜力，这些应用涉及高分辨率宽测绘带遥感、3-D 成像以及雷达通信一体化。该方案通过概念验证实验进行了验证。这项工作展示了涡旋 EM 波的新应用，为新一代和未来 SAR 系统的发展提供了便利。