Abstract This paper presents a compact dual-band multiple-input multiple-output (MIMO) fractal antenna based on a novel butterfly-flock iterative ring structure. Each MIMO element is formed through three fractal iterations, where every added ring is half the size of the previous one and rotated by 90° in anti-phase, creating extended current paths and inherent spatial polarization diversity. The antenna achieves wide operating bands of 1.1–5.6 GHz and 7.4–9.7 GHz, covering GPS, 3G, WLAN, LTE, WiMAX, 5G, and satellite communication systems. Compared with earlier designs, the proposed structure demonstrates improved diversity performance, including a low Total Active Reflection Coefficient and a low Channel Capacity Loss. With a compact size of 30 × 40 × 0.8 mm 3 , the design is suitable for integration into modern portable wireless devices.
Abed et al. (Fri,) studied this question.