A small planar 4G antenna with a coupled-fed monopole and a directed-fed monopole for mobile handset application

This paper proposes an eight-band LTE/WWAN antenna for mobile phone application. The proposed antenna, which has advantages of dual wide bands and small dimension, is composed of a meandered coupled-fed monopole that excites a fundamental mode at 718 MHz and a meandered directed-fed monopole that excites the other fundamental mode at 918 MHz. By adjusting the parameters of the proposed design, the two resonant modes gather to form a low operation band (690-975 MHz) based on the 6-dB return loss for LTE 700, GSM 850, and GSM 900 applications. The higher modes of the two resonant modes produce a high operation band (1600-2200 and 2268-3000 MHz) for GSM 1800, GSM 1900, UMTS 2100, LTE 2300, and LTE 2500 applications. The overall dimensions of the proposed antenna are 120×65×0.8 mm³ that consists of an antenna portion of 10×65 mm² and a ground plane of 110×65 mm². The antenna´s operation bands and size are suitable to apply in smart phone.