A compact loop antenna with seven resonant modes for smartphones

Abstract
In this paper, a compact loop antenna with a compact volume of only 60×8×5 mm 3 for smartphone applications is presented. The loop antenna consists of a 3-D meandered loop and three parasitic elements to generate seven resonant modes. The 3-D meandered loop is used to generate four resonant modes, the 0.5-λ, 1-λ, 1.5λ and 2-λ modes, while the three parasitic elements are used to generate three other resonant modes. With seven resonant modes, the loop antenna forms a two wide frequency bands, a low-frequency band of 0.822-0.977 GHz and a high-frequency band of 1.65-3.6 GHz to cover the GSM850. GSM900, DCS1800, PCS1900, UMTS2100, TD-SCDMA Band A & F, LTE2300, 2.4G WLAN, LTE 2600, and LTE 3500 systems.