An efficient tunable decoupling and matching method for simplifying compact dual‐band mobile terminal antennas

Abstract

An efficient tunable decoupling and matching method is proposed for simplifying compact mobile terminal antennas, that operates simultaneously in two independent bands. To enable carrier aggregation, the lower band in this design is tunable over the frequencies of interest for the traditional standards, while the upper band provides a fixed broad bandwidth to meet the bandwidth demands of 5G mobile terminal applications. Multi-element antenna systems, containing a simple antenna structure combined with tunable networks to realize dual-band decoupling and matching function, are systematically studied. The network structures are simplified to minimize the losses incurred in maintaining a good performance. To demonstrate the proposed approach, a two-element antenna system is developed in which the lower band can be tuned over the frequency range of 2.25 to 2.75 GHz, and the broad upper band can cover frequencies from 4.42 to 6.21 GHz. Good performance such as high total efficiency, low envelope correlation coefficient and stable radiation patterns, can be observed, thus, validating the effectiveness of the proposed method for simplifying the antenna structure.