Low-Cost Air Gap Metasurface Structure for High Absorption Efficiency Energy Harvesting

Table 3

Measured performance comparison of the proposed design and other referred metasurfaces.

Ref.	Structure	Efficiency (%)	Material (metasurface, combining network)	Unit-cell area (mm^3), thickness [λ]	Cost (unit cell)
[7]	G-CSRR (11 × 11)	83% (5.55 GHz)	Rogers duriod RT5880, —	342.25, 0.015^†	High
[8]	ELC (13 × 13)	93% (3 GHz)	Rogers TMM10i, —	56.25, 0.026^†	High
[16]	SRR + hollow cylinder (10 × 10)	97.3% (2.45 GHz)	Copper + PTFE, —	400, 0.074^†	High
[17]	Split-loop on air (20 × 20)	97% (2.45 GHz)	Air, —	392, 0.067^†	Low
[18]	ERR (8 × 8)	78% (3 GHz)	Rogers TMM10i, Rogers 5880	232.56, 0.016^†	High
[19]	ELC (8 × 8)	86% (2.45 GHz)	Rogers RO4350, Rogers RO4350	240.25, 0.051	High
Prop.	ELC (8 × 8)	84.4% (2.41 GHz)	F4B/air, S7136	484, 0.071	Low