A space-efficient coupling element antenna for WWAN applications

A space-efficient capacitive coupling element antenna which covers the Wireless Wide Area Network (WWAN) low and high bands from 700 to 960MHz (LTE700&GSM850/900) and 1.7 to 2.7 GHz (DCS/PCS, UMTS, WLAN2400, LTE2500) is presented here. The main difference of this novel antenna structure versus the plain coupling element antennas is its hollowed structure: the main metal plate of the CE have been made hollow to be more space efficient and leave space for other radiators or electronic components. The design can be divided in two main steps. Firstly, a metal strip of 1mm width is used to excite the currents over the system ground plane which is the dominant radiation mechanism at low frequency. Then, the saved space is used to accommodate a higher-band antenna to cover 1.7-2.7GHz still keeping a high isolation between the two feeds. The low-band performance of the antenna is supplemented with the measurement results obtaining a total efficiency higher than 50% between 700-960MHz which is a very competitive value when compared to today´s handheld mobile communication device antennas.