A single feed, dual‐band frequency tunable planar inverted‐F antenna (PIFA) is presented for mobile handheld device applications. The proposed antenna is designed using the transmission line model. The dual‐band frequency tunability is achieved by varying the capacitance of the varactor diode between 4.15 pF (0 V) and 0.72 pF (15 V). The measured impedance bandwidth of −6 dB is realized from 0.8 to 0.98 GHz for the lower band and 1.65 to 2.2 GHz for the higher band. The designed antenna provides the independent frequency tunability for both the bands without disturbing each other. The maximum antenna gain is estimated 2.64 dBi for the proposed PIFA. Also, it has a maximum efficiency of ~85% for the mobile handheld device. In addition, the proposed PIFA is investigated with SAM phantom model for head and hand, found to be within the acceptable SAR limit of 1.6 W/Kg.

中文翻译：

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适用于移动手持设备的双频段可调谐平面倒F型天线

提出了一种针对移动手持设备应用的单馈电，双频带频率可调平面倒F型天线（PIFA）。建议的天线是使用传输线模型设计的。通过在4.15 pF（0 V）和0.72 pF（15 V）之间改变变容二极管的电容来实现双频段频率可调性。低频范围从0.8到0.98 GHz，高频范围从1.65到2.2 GHz，实现了-6 dB的测量阻抗带宽。设计的天线可为两个频段提供独立的频率可调性，而不会互相干扰。对于建议的PIFA，最大天线增益估计为2.64 dBi。此外，对于移动手持设备，它的最高效率约为85％。此外，使用SAM幻影模型对拟议的PIFA进行了头部和手部研究，