LTE handset antenna with closely-located radiators, low-band MIMO, and high efficiency

Performance of a multi-element handset antenna operating at LTE frequencies is reported. The antenna elements have metal parts that are closely located physically and electrically. Matching circuits are used to reduce mutual coupling and to improve the efficiency. With a combination of active and reactively loaded radiators and fixed matching circuits, an embedded radiation efficiency better than 80 % at 698-960 MHz and better than 60% from 1.7 GHz upwards is achieved. By using identical antennas in both ends of the device, two-element Multiple-Input Multiple-Output (MIMO) operation can be obtained in simulations with efficiencies up to 60 % at low band and better than 60 % at high band.