基于时空编码数字超表面的雷达散射截面积缩减及波达角估计方法

Simultaneous Direction of Arrival Estimation and Radar Cross-section Reduction Based on Space-time-coding Digital Metasurfaces

传统的波达角(DOA)估计方法的实现通常基于相控阵天线系统,而其高昂的硬件成本限制该技术在不同领域的应用和推广,此外相控阵天线普遍不具备隐身性能,其在工作频段内雷达散射截面积(RCS)普遍较高。为解决上述问题,该文在时空编码(STC)理论的基础上提出了一种基于超表面同时实现RCS缩减和DOA估计的方法,并利用一款毫米波超表面对算法进行了验证。实验结果表明,该方法实现的波达角估计误差在1°以内,同时RCS缩减大于10 dB,为DOA估计和RCS缩减功能的集成提供了全新的思路,具有高性能、低成本等特点。

The traditional Direction Of Arrival(DOA)estimation is typically based on phased array antenna systems.However,it is greatly limited by the high hardware cost for applications in various fields.In addition,conventional phased array antennas also suffer from the high Radar Cross-Section(RCS),which cannot be employed for stealth purposes.To address these issues,we propose a new algorithm based on the Space-Timecoding(STC)strategy for simultaneous DOA estimation and RCS reduction,which is further experimentally verified using a metasurface in the millimeter band.The results demonstrate the excellent performance of the proposed DOA method with an error below 1°.Meanwhile,a good RCS reduction of over 10 dB is achieved in the bandwidth of interest.The proposed algorithm paves a new path to integrating DOA estimation and RCS reduction with a single metasurface,with the advantages of low cost and good performance.