A Simultaneous Study on Wire-Loop, Plate-Loop, and Plate Antennas for Wideband Circular Polarization

Table 1

Comparison with other studies.

Study	Loop shape	Method for circular polarization	ARBW (%)	OLBW (%)	Gain (dBi)	Fre (GHz)
[1]	Square	Perturbation segment	1.02	1.02	7.6	1.57
[2]	Circular		12.7	12.7	7∼8	2.5
[5]	Hexagonal	Loop-shaped deformation	4.0	4.0	—	—
[7]	Rectangular		4	—	9.1	1.5
Present	Square	Vertical, branched feedline	39	36	7.3	3

ARBW: 3 dB axial ratio bandwidth; OLBW: overlapped bandwidth for ARBW, 3 dB gain-drop bandwidth, and bandwidth of VSWR <2;
Fre: frequency; −: not described.