Design of Wideband Circular-Slot Antenna for Harvesting RF Energy

Table 1

Comparison of the proposed wideband circular-slot antenna with the related work.

Ref […]	Electrical Length ()	Description	Operating frequency (GHz)	FBW (%)	Maximum realized gain (dBi)	Substrate
[18]	1.52 × 1.52	Coupled slotted-gap with a semicircular slot.	5.150–12.470	78	4.5	FR-4 (4.3)
[24]	2.70 × 1.70	Coupled annular ring with a centralized feed point.	5.700–6.300	10	5.7	RO6002 (2.94)
[28]	0.70 × 0.71	Quasi C-shaped with a centralized signal strip	5.150–7.100	31	3.6	RO4003 (3.55)
[37]	1.10 × 1.10	Electromagnetically coupled fed a circular pattern	2.410–2.500	3.6	NA	FR-4 (4.5)
[38]	0.95 × 0.95	Slanted rectangular slots pattern	1.820–3.080	51	1.5	FR-4 (4.7)
[33]	0.80 × 1.10	Triangular ground with an asymmetrical excitation	1.42–2.7	62	2.2	FR-4 (4.3)
[33]	0.63 × 0.63	Single fed fractal pattern integrated diagonally with a ring slot	1.370–1.770	25	4.1	FR-4 (4.4)
This work	0.61 × 0.700	Circular slot with a pair of orbital circular and extended rectangular slots pattern	1.55–3.14	73	4.32	FR-4 (4.7)

: guided wavelength at the lowest operating frequency (f_o). NA: not available.