Watchstrap-Embedded Four-Element Multiple-Input–Multiple-Output Antenna Design for a Smartwatch in 5.2–5.8 GHz Wireless Applications

Figure 3

(a) Configuration of the two-element MIMO antenna at angle θ in free space. (b) Measured S11 and S21 at different degrees of bending for the two-element MIMO antenna in free space. (c) Measured radiation pattern for the two-element MIMO antenna bent at different angles in free space. (d) Measured and simulated S11 and S21 at the bending angle of 30° with the watchstrap for the MIMO antenna.

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(b)

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