High-speed real-time hand effect tuning algorithm in hand-held terminal

In this paper, impedance tuning algorithm is proposed. To improve antenna radiation performance, antennas have high radiation efficiency and mismatched efficiency. The mismatched efficiency can be improved by the impedance matching circuit and matching algorithm. The proposed algorithm uses only standing wave ratio (SWR) information. The proposed algorithm is high-speed predicting antenna impedance algorithm. The algorithm running time is less than 25 ms.

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