A. A. . Balabel, H. A. . Malhat, and . S. H. . Zainud-Deen, “Octafilar Helical Antenna for Wireless In-Body Capsule Endoscopy Applications”, J. Adv. Res. Appl. Mech. , vol. 44, no. 1, pp. 8–14, Nov. 2020.