Antenna efficiency plays a critical role in overall smartphone RF performance. However, current trends in smartphone industrial design and RF requirements, especially with the upcoming transition to 5G, mean that smartphones must fit more antennas into less space and/or increase the bandwidth of existing antennas. In short, antenna tuning is more important than ever. This article introduces four key elements to understand about antenna tuning in 4G and 5G mobile devices. Download the full article for more information.