Wideband Slot Array Antenna Fed by Gap Waveguide with Right-Handed Circular Polarization and High Gain

Table 2

Comparison between proposed and reported millimeter-wave CP array antennas.

Year/reference	(GHz)	Impedance B. W. (%)	AR B. W. (%)	Max. gain (dBi)	Number of radiation elements	Feeding technology
2016/[4]	20	15.9	13.8	25.9	64	SIW
2014/[46]	22.7	25.5	17.9	18.7	16	SIW
2016/[47]	28.3	28.5	14	18.2	64	Stripline
2017/[48]	30	16	16	32.8	256	CPW
2018/[22]	30	5	6	22	16	RGW
2019/[20]	31	22	21.8	23.5	64	RGW
2021/[34]	35	8.45	8.45	31.5	200	RGW
This paper	28	20.5	10	31.6	256	RGW