(c) (d)
Fig. 6 matched current and 2.45GHz radiation pattern. (a) model of a typical smart watch. (b) S-parameters of free space and forearms loading. (c) XOY plane radiation pattern of Port1 with the forearm. (d) XOY plane radiation pattern of Port2 with the forearm.
Conclusion: In this article, a simple but useful decoupling technique, which two radiation patterns have an orthogonal characteristic of 90-degree rotational symmetry, achieving a high isolation with 50dB, is proposed. A capacitive or inductive load is a function of frequency, the S21 notch frequency decreasing as the value of the capacitor or inductor increases. So, it is flexible to decouple for multiband applications with the variation of lumped elements if tunable switches for aperture tuning are available.
 2021 The Authors. Electronics Letters published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Received: xx January 2023 Accepted: xx March 2023
doi: 10.1049/ell2.10001
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