Designing Hand-Immune Handset Antennas With Adaptive Excitation and Characteristic Modes

This article presents a design process for a hand-immune mobile antenna system. Characteristic modes (CMs) of a mobile phone and hand combination are analyzed to find the desired modes with good radiation properties. The efficient excitation of these modes is implemented by utilizing the antenna cluster technique. The proposed mobile antenna design has a small ground clearance of only 2 mm and can cover the 700–960 MHz low band, 1700–2700 MHz middle-high band (MHB) with two multiple-input–multiple-output (MIMO) antennas, and the 3300–3800 MHz high band with four MIMO antennas. The measurement results confirm that the proposed CM analysis-based design method in a realistic use case leads to a robust antenna design with competitive performance.

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