Figure 5a

Figure 5a Fabricated antenna: front view.

Figure 5b

Figure 5b Fabricated antenna: back view.

Figure 6

Figure 6 Antenna S-parameters.

Figure 7

Figure 7 Simulated S12 of the original design compared with measured S12 of the final antenna.

Figure 8a

Figure 8a MIMO antenna patterns: 2.45 GHz E-plane.

Figure 8b

Figure 8b MIMO antenna patterns: 2.45 GHz H-plane.

Figure 8c

Figure 8c MIMO antenna patterns: 5.8 GHz E-plane.

Figure 8d

Figure 8d MIMO antenna patterns: 5.8 GHz H-plane.

CONCLUSION

A new design approach uses odd-even mode analysis to design a MIMO antenna decoupling structure. Analysis and calculation of decoupling conditions is done first, before selecting and optimizing the structure. To avoid influencing performance in the lower frequency band, a defective ground structure is selected to improve isolation in the higher band. The introduction of these two structures completes the design of a dual-frequency high isolation MIMO antenna, and the feasibility of this method is verified through experiments. The antenna has good radiation and isolation characteristics, suitable for miniaturized mobile communications.

ACKNOWLEDGMENTS

This work is supported by Sichuan Science and Technology Program (Grant No.2020YJ0271).

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