Compact Four-Port Dual-Sense Circularly Polarized Stack-Up Patch Antenna for UHF/MW-RFID MIMO System

Figure 13

Simulated and measured axial ratio as a function of θ angle from the broadside, in the XZ and YZ planes at 2.45 GHz: (a) Port 3 and (b) Port 4.

(a)

(b)