Thanh, Tu Duong Thi, Pham Duy Quan, Phan Huu Phuc, and Hoang Thi Phuong Thao. “A Penta-Band Antenna Using Symmetrical DGS for RF Energy Harvesting in IoT Applications”. Engineering, Technology & Applied Science Research 15, no. 2 (April 3, 2025): 22028–22034. Accessed May 13, 2026. https://etasr.com/index.php/ETASR/article/view/10138.