Dual-Dipole UHF RFID Tag Antenna with Quasi-Isotropic Patterns Based on Four-Axis Reflection Symmetry

Table 4

Simulated gain values of the three commercial tag antennas in three planes (Unit: dB).

Gain	𝑋𝑍	𝑌𝑍	𝑋𝑌	Gain deviation
Invengo TF8023 max.	4.89	4.89	1.97	4.02
Invengo TF8023 min.	1.94	1.00	0.87
Impinj H47 max.	4.83	4.83	1.59	4.39
Impinj H47 min.	1.56	1.41	0.44
UPM frog 3D max.	4.87	4.87	2.61	5.12
UPM frog 3D min.	1.17	1.40	−0.25