In this study, the differential substrate integrated waveguide (SIW) slot antenna array is proposed with intrinsic common-mode (CM) rejection. Through field analysis, it is found that the SIW is a natural differential transmission line which can only transmit differential signal due to the characteristics of hybrid electromagnetic boundary perfect electrical conductor and perfect magnetic conductor. Hence, it can also be seen as a natural balun with intrinsic CM suppression. Thus, a compact 1 × 4 differential SIW slot antenna array with high CM rejection can be designed using the differential microstrip transition structure which has little conversion between differential-mode (DM) and CM. For the design of differential SIW passive device, the DM equivalent half circuit is a single-ended SIW device with height halved. Further, the 4 × 4 differential SIW antenna array with high CM rejection can be designed with a T-shaped differential SIW four-way power divider. The 1 × 4 and 4 × 4 differential SIW antenna arrays are fabricated and good agreements between the simulated and measured results demonstrate the validity of proposed configurations.

中文翻译：

---

具有固有共模抑制能力的差分SIW缝隙天线阵列

在这项研究中，提出了具有固有共模（CM）抑制特性的差分衬底集成波导（SIW）缝隙天线阵列。通过现场分析发现，由于混合电磁边界完美电导体和完美磁导体的特性，SIW是一条自然的差分传输线，只能传输差分信号。因此，它也可以看作是具有固有CM抑制功能的自然巴伦。因此，可以使用差分微带过渡结构设计出具有高CM抑制比的紧凑型1×4差分SIW缝隙天线阵列，该结构在差分模式（DM）和CM之间转换很少。对于差分SIW无源器件的设计，DM等效半电路是高度减半的单端SIW器件。进一步，具有高CM抑制比的4×4差分SIW天线阵列可以设计成带有T形差分SIW四路功率分配器。制作了1×4和4×4差分SIW天线阵列，仿真结果与测量结果的良好一致性证明了所提出配置的有效性。