This letter presents a 4 × 4 single-layer dual-band array antenna operating in the K - and Ka -band using gap waveguide (GW) technology. Radiating elements consist of I-shaped slots located on the top plate of the antenna and backed by a novel coaxial cavity with the dual-frequency operation. The antenna presents two ports, one for each band, and radiates a directive far field pattern with linear polarization. A single-layer wideband corporate-feed network is used to excite the cavities. In addition, a diplexer is integrated as part of the network to separate both working bands. Experimental results show impedance and radiation pattern bandwidths larger than 2 GHz in both bands.

中文翻译：

---

双频单层缝隙阵列天线 ķ/K a隙波导技术的宽带双模谐振器

这封信提出了一种4×4单层双频阵列天线，该天线在 ķ - 和 K a 使用间隙波导（GW）技术的宽带。辐射元件由位于天线顶板上的I形槽组成，并由带有双频操作的新型同轴腔支撑。天线具有两个端口，每个端口一个，并辐射具有线性极化的定向远场方向图。单层宽带公司馈送网络用于激发空腔。另外，双工器被集成为网络的一部分，以分隔两个工作频段。实验结果表明，两个频段的阻抗和辐射方向图带宽均大于2 GHz。