Small-Sized, Tri-Band, Two-Antenna System Aimed for 4 × 4 Gbps Notebook Applications

A very-low-profile (VLP), two-antenna system formed by two identical monopoles facing each other with a decoupling inductor is presented. The two-monopole design capable of covering the 2.4-GHz (2400-2484 MHz), 5.2-GHz (5150-5350 MHz), and 5.8-GHz (5725-5825 MHz) wireless local area network (WLAN) bands merely occupied a small size of 5 mm h 42 mm. The two antennas were closely packed with 1-mm (0.008λ at 2.4 GHz) spacing only and required nearly no separation distance. An inductor connecting the open ends of the monopoles was employed to reduce the mutual coupling in the 2.4 GHz band. Over the 5.2/5.8 GHz bands was good isolation achieved owing to the devised arrangement of the antenna current nulls of higher-order resonance.