A low-profile and dual-wideband circularly polarized (CP) shared aperture antenna is demonstrated for satellite-assisted Internet of Things (SATA-IoT) communications. It comprises an X-band antenna and a$4\times 4$Ka-band antenna array, both magnetoelectric (ME) dipole structures with complementary structures, and only have$0.08{\lambda }_{\mathrm { low}}$thickness. Four mesh-structure dipole arms are utilized for the X-band antenna to integrate the X/Ka band antenna into the limited aperture while maintaining good isolation. Meanwhile, stubs and a sequential rotation feeding (SRF) network are adopted to improve the axial ratio (AR) performance of the two antennas, respectively. The measured results indicate that the antenna achieves an overlapped bandwidth ($|S_{11}|\lt -10$dB, AR ¡ 3) of 10.8% (8.7–9.7 GHz) and 29.32% (25.73–34.57 GHz), with isolations greater than 20 dB in both bands. The measured peak realized gains are 8.9 and 15 dBi, respectively. The proposed antenna realized exceptional low-profile and dual-wideband CP performance, making it a promising candidate for SATA-IoT communications.

This paper presents a novel composite phase unit (CPU) designed for an orbital angular momentum (OAM) metalens (ML), featuring a 3D-printed middle metal layer (MML) with non-uniform height. This design reduces slot length variations and mitigates bandwidth shrinkage resulting from passband overlap. It also aligns the frequency response of each CPU, ensuring that peak transmission occurs at the center frequency. The CPU consists of an MML sandwiched between two polarization grids (PGs), forming a quasi-Fabry-Pérot (FP) cavity. A high-resonance metal slot structure within the MML improves the transmission amplitude. To achieve a full 2π phase shift range, the CPU combines propagation, geometric, and resonant phase-control mechanisms. The non-uniform-height MML is fabricated via selective laser melting (SLM) using AlSi10Mg, which demonstrates the capability of 3D printing to fabricate complex structures. Experimental results show that the ML achieves a measured gain of 26.81 dBi at 36 GHz and a 3-dB gain bandwidth of 16.2%, representing significantly improved bandwidth retention relative to the CPU’s 3-dB transmission bandwidth of 12.8%. The proposed OAM metalens demonstrates high mode purity and stable transmission, which enables efficient multichannel wireless communications that are critical for Internet of Things (IoT) applications. This structure significantly improves link capacity, energy efficiency, and system-level simplicity in multichannel IoT systems.

Emerging additive manufacturing (AM) technologies, specifically additively manufactured electronics (AME), 4-D printing, and origami, are reshaping the design capabilities and functionalities of contemporary electronic devices. Cutting-edge 3-D/4-D printing technologies facilitate the prototyping and realization of complex electronic functions that are challenging to conventional methods. This article provides a comprehensive overview of the evolving techniques in AME, 4-D printing, and origami, employing multimaterials (conductive and dielectric materials) and shape-memory materials (SMMs) to fabricate functional electronic components and devices. Additionally, the overview delves into the state-of-the-art AME and 4-D-printed electronic components across diverse fields, including biomedical electronics, space engineering, and the advancements in the next-generation wireless communications and sensing.