Figure 10 shows XoZ and YoZ radiation patterns at 3.445 and 4.046 GHz with Port 1 driven. Because the antenna is arrayed on a rotated grid, only the radiation patterns of Antenna 1 are shown. Note that when Φ=90 degrees, the Eθ component tilts to the direction of the wide side ACD (see Figure 2). Patterns for Antenna 1 through 4 tilt in four different directions, which promotes higher antenna isolation and lower ECCs.

Figure 10

Figure 10 Measured and simulated radiation patterns of Antenna 1 driven at Port 1.

CONCLUSION

A low-profile four-port circular patch antenna provides a MIMO capability covering the 5G N77 band (3.3 to 4.2 GHz). Its application is 5G intelligent terminal equipment, especially for mounting on metal surfaces. Each port delivers wideband operation by merging two modes. The radius of the circular patch is 22 mm and the height is only 2.4 mm. This antenna’s structure and design process is outlined and prototype testing verifies its feasibility.

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