A miniaturized stacked patch antenna with circular polarization in GPS L1 band and dual linear polarization in WiMAX band for IoT (Internet of Things) applications is proposed. A novel technique has been introduced to enhance a second mode in dual-band patch antenna, by adding pi shaped slots and stacking another reflective patch, with shorting pins in between. The upper patch, thus, acts as an independent receiver in WiMAX band using enhanced second mode of the lower patch. At GPS L1 frequency of 1.575 GHz, the compact antenna of volume 0.13 λ₀ × 0.13 λ₀ × 0.067 λ₀ (λ₀ is the free-space wavelength at 1.575 GHz) achieves a wide half-power beamwidth of 104 ± 5°. The measured results exhibit an impedance bandwidth of 5.71% in WiMAX (3.4 GHz–3.6 GHz) band along with symmetrical radiation patterns for both horizontal and vertical polarizations of the transmitter. The fabricated prototype, with a radiation efficiency greater than 85%, proves to be highly efficient in portable devices for multipath spaces in IoT.

提出了一种微型堆叠式贴片天线，其在GPS L1频段具有圆极化，在WiMAX频段具有双线性极化，可用于IoT（物联网）应用。通过添加pi形缝隙并堆叠另一个反射贴片（之间有短接针脚），已引入了一种新颖的技术来增强双频贴片天线的第二种模式。因此，上部补丁使用下部补丁的增强的第二模式在WiMAX频带中充当独立的接收器。在1.575GHz的，体积0.13λ的紧凑的天线的GPS L1频率₀  ×0.13λ ₀  ×0.067λ ₀（λ ₀是在1.575 GHz处的自由空间波长），实现了104±5°的宽半功率波束宽度。测量结果显示，在WiMAX（3.4 GHz–3.6 GHz）频带中，阻抗带宽为5.71％，并且发射机的水平和垂直极化均具有对称的辐射方向图。辐射效率大于85％的预制原型在物联网中多路径空间的便携式设备中被证明是高效的。