Single-Fed Broadband CP Bidirectional Antenna with Double-Layer Diagonally Aligned Plates for Universal UHF-RFID Applications

Table 2

Characteristics of the proposed antenna.

Characteristic		840 MHz		900 MHz		960 MHz
		Simulated	Measured	Simulated	Measured	Simulated	Measured
|S11| (dB)		−16.56	−13.99	−30.87	−25.03	−14.6	−15.35
AR (dB)		1.92	0.46	1.38	0.79	0.13	1.36
LHCP gain (dBic)		5.05	4.66	5.57	5.16	5.89	5.72
RHCP gain (dBic)		4.94	4.28	5.22	5.2	5.32	4.89
LHCP HPBW (degree)	xz plane	90	98	86	97	82	88
	yz plane	56	52	56	52	56	56
RHCP HPBW (degree)	xz plane	92	79	84	97	76	88
	yz plane	56	62	54	63	54	65
		Simulated			Measured
|S11| ≤ −10 dB bandwidth		772.19 – 1014.6 MHz, 27.13%			759 – 1011 MHz, 28.47%
AR ≤ 3 dB bandwidth		675 – 1000 MHz, 38.8%			648 – 1110 MHz, 52.55%
Global bandwidth (%)		675 – 1000 MHz, 38.8%			648 – 1011 MHz, 43.76%
Pattern		Bidirectional