Design of Low-Loss Air Material Achieving High-Throughput Signal Transmitting Antennas

• Designed Air-Material antennas significantly outperform commercial ones. • Polyphenylene oxide optimally balances signal transmission and practicality. • Supercritical CO 2 foaming yields ultra-low dielectric loss in various materials. • A comprehensive evaluation framework for high-frequency materials is established. To meet the demands of higher-throughput signal transmission, the development of 5G and 6G communication technologies is accelerating. However, Critical antenna components suffer from significant transmission losses at high frequencies, underscoring the need for low-dielectric materials. In pursuit of low-loss material offering highly overall performance for high-performance antennas, we employed advanced supercritical carbon dioxide (scCO 2 ) mold foaming technology to design high wave-transparent structure within five different polymer matrices (Polyetherimide, Polyphenylene Oxide, Polycarbonate, Ultra-High Molecular Weight Polyethylene, and Cyclo-Olefin Copolymer), thereby fabricating low-loss Air Materials. Through simulation and measurement, it is found that antennas incorporating Air Materials achieved a gain of up to 9.8 dBi and an efficiency of 96.2% at 10 GHz, compared to widely used commercial FR-4-based antennas (5.5 dBi, 76%). In Wi-Fi systems, the developed antenna reaches a signal rate of 49 Mbps, demonstrating notable advantages in both transmission distance and energy efficiency. In addition to signal transmission performance, PPO-based Air Material exhibits the best overall performance, featuring considerable thermal resistance, good compressive modulus, outstanding flame retardancy, ultra-low dielectric properties and high hydrophobicity. In summary, this work introduces some novel low-loss Air Materials suitable for high-performance antennas, offering a promising pathway for next-generation communication technologies.